It does not have the "Philips" logo on it, is this real?

Please help

Hi All, thank you for the add, I'm 63 years old, from Sydney Australia, I did a radio broadcasting technician course back in 1978 and haven't done anything with it since because of ill health at an early age. I ended up doing every different form of employment from loading trucks to sales for a pharmaceutical company and a variety of things in between. After two transplants, one cancer and over 40 major operations, I've started to buy some old amps, CD, tape decks and turntables because I have now retired...... I think everyone is lucky I didn't pursue my first vocation. Here I am needing advice, even though I have surprisingly fixed quite a few units? Maybe 50/50 at the moment get thrown out. Please be kind, I may ask some silly questions.

Hello all,

I have a quad (x4) of NOS 600 ohm line transformers for sale

Made by Control Dynamics, part number is CD1119

These transformers are intended for telecoms, voice-frequency applications and have center-tapped 600 ohm primary and secondary windings on an ungapped ferrite core

They measure approx 16mm cube

I'm thinking USD 10 for lot plus postage or open to offers

Cheers, Ralph

https://audiofile.net.au/

Hello all,

I have some Harbuch 600 ohm line input transformers for sale

These transformers are high quality, Mu-metal shielded, stud mounted units intended for line input applications and have center-tapped 600 ohm primary and 600 ohm secondary windings

Pulls from a mixing console

The leads are approximately 150mm long

I'm thinking USD 20 each plus postage or open to offers

Cheers, Ralph

https://audiofile.net.au/

Hello,
welcome to my new tool for the Behringer DEQ-2496.
I love this gadget but turning knobs and pressing small buttons is not what I
like.
So I decided do create DEQ2496-Control because Simon Rhode (seoman)
stops his project DEQ2496-Remote. I've tested my Tool up to Windows 7 64
bits.
DEQ2496-Control is tailored to my personal needs. May be that I expand the
functionality in the future but everything I need is working.
You can use it free of charge. Use it on your own risks.


Please read the attached PDF before you use it.

DEQ2496Control-V099-Setup


Kind regards
BigD

Hi,

I want digital audio input capabilities to Raspberry Pi. Is there any SPDIF/COAX to USB converters available?

Thanks and Regards,
WonderfulAudio

Murton-Pike Systems Vendor Thread

Single thread combined from others in Vendor's Bazaar.

PCBCAD51 available at Murton-Pike Systems

Touch screen compatible.

2018 Windows full version of PCBCAD51 PCB DESIGN SOFTWARE with 127 LAYER AUTOROUTER.

Runs on Windows XP (SP3) , Windows Vista and Windows 7, Windows 8 and Windows 10.

This is a mature product with no bug list, if I find a bug it is fixed immediately.

Support for this product is second to none, you are supported by the guy who wrote this software.

Schematic and PCB symbol designer wizards.
Auto creates SIL, DIL, circular and QUAD PCB footprints from your parameters.

Schematic entry with auto convert schematic to PCB ratsnest, unconnected pin scanner and single ended net scanner.

PCB entry with 127 layer rip up and retry auto-router with clearance and continuity check.

360 degree rotations of pcb components with obround pads.

Integrity checker, compares schematic and PCB for differences.

Component locater.

Parts list output.

Schematic/PCB component auto-renumbering and re-annotation.

RS274X Gerber file generator and NC/Excellon drill file generator.

Pick and place file generator with fiducial option.

3D PCB viewer module.

Output schematic to printer auto-sized.

Output PCB to printer in 4:1, 2:1 and 1:1 scaling, inversion and mirroring about x and y axis.

Merge schematics and merge PCB's.

Library scanners for fast component selection.

Gerber file viewer (PCBCAD51 files only)

Component locater, block-mode for repeats, shifts, rotations etc.

Net optimizer for shortest routes.

Auto component placers for minimum routing.

Recursive auto-autoplace, rotational autoplace and swap autoplacer.

Auto-place and route recursively function for lazy PCB design.

Unconnected pin scanner.

Forward annotation function from schematic to PCB.

Screen capture to bitmap file in schematic and PCB entry.

PCB's up to 50 by 50 inches.

127 copper layers.
127 resist layers.
Copper pours, each layer can be connected to a different NET.

2 silk layers (upper/lower)

Comes with symbol libraries, 4000, 7400, smd4000, smd7400 and general as standard.

User manual in each module

This is the full version and not a crippled, time limited or downsized version.

This is a fully integrated package and not a suite of amateur free programs cobbled together.

Fully supported package with email and phone help lines.

Note: This is the 2018 version and not an obsolete version.

Used these in the Orion 4 speakers. They are used for approx 3 years in a smokefree livingroom.
In perfect condition

Reducef: Asking 170 euro each.

Hi,

We know that at the box tuning frequency the port produces all the SPL which is 180 degrees out of phase. What if we add another enclosure tuned at the same frequency to get 360 degree phase, i.e. in phase with the active driver. Lets ignore the extra space needed for the moment. Does the idea have any merit in terms of flattening the phase?


Warm Regards,
WonderfulAudio

A titan among internet audiophiles has recently passed.

I’m quite shocked and saddened by his passing, his recent writings were so full of life and enthusiasm.

Needless to say he was a champion of diy gear and the reason why many or us know about Elekit.

Anybody can help me. Need philips 15 AH824 service manual.

I was going to knock a pair for experimental purpose since I have Graham /Stirling woofers and other bits and want to try different tweeters (scan and Hiqup) but since it still takes considerable effort without proper woodworking shop I will make a proper ones after experimental phase is over hence the inquiry. A nice pair will be considered as well

Hey, guys,

I think this qualifies as a DIY guitar question because I only see a semi-diy solutions. 🙂

I want a cheap guitar that I could take with me when I travel, specifically, when I fly. I always travel light, carry-on only: not very often but regularly. I miss my daily practice even when I am away a week, it gets especially bad when we go on a family trip for 2-3 weeks.

The shortest headless full-size travel guitar I could find is still way too long: 28 inches, and the length limit on the carry-on is 24. What's worse, I cannot have it as a personal item since the size restrictions are even tougher: it is supposed to fit under the seat.

Long story short, I thought I would just unscrew the neck of one of my strats but the standard neck is still too long to fit into the carry-on! My carry-on bag, which is pretty standard and is allowed by most airlines, internally measures as 19" by 13" (48 cm x 33 cm). SO, I thought - a headless strat, maybe? I found this one on amazon: https://www.amazon.com/Volgoa-GTWT-01-6-String-Headless-Electric/dp/B0BGL56M94

I think it should fit if I unscrew the neck. What do you think, folks? Any other ideas? I don't really want to pay through the nose for this too, $200 is probably about right, give or take, much more would be hard to justify.



P.S. This one looks pretty nice too, and I have my birthday in a week, might be able to persuade my wife that it would make a really nice gift...

Hello friends... I'm looking for the name of these components in the power supply stage. The amplifier is a SoundMagus PK1400.4. The components appear to be transistors, but I've tried several without getting satisfactory results. Two of them have a number (23), one only shows the letter S, and the last one didn't have a number because it was completely blown. I hope someone has an amplifier in their possession and can guide me. Greetings, friends, and have a good night.

So I finally have the DATS v3 to measure my custom made field coil full range driver. And most of it is ok, but I get a way too high Vas. My guess is that it has to do with the phase plug that doesn't move, while a dust cap does. So entering the diameter the usual way, might overestimate the Vas. And using the Vas that I have now in WinISD results in hideously huge boxes. How to correct for this?

Hello Folks!

I am currently in the process of building an PR tuned enclosure.
After searching for available PRs it looks like the market is quite thin. But maybe there is another option?

How about using a active driver with nothing connected to the voice coil or maybe even with the Magnet and voice coil assembly removed as a PR?
It looks like many of the available PRs are already just normal available woofers with just the magnet and VC removed.

Let us take a look at this for example: PURIFI PTT6.5PR-NF1-01 vs PURIFI PTT6.5X08-NFA-01

The PR very much looks like it uses the exact same parts as the actual woofer. However it somehow doesnt add up.
Qms and Qmpr should be exactly the same as these values are just related to the mechanics, same for Vas / Vapr.
Vas is almost the same on these, but Qmpr is much higher than Qms?
Xmax is different but this makes sense as the active chassis is likely limited by the voice coil leaving the magnet field vs the PR is only limited by the suspension.

If we take a different manufacturer it gets even worse:



So whats going on here? Are they using different materials for the suspension to get different characteristics? Is the voicecoil influencing anything?

Lets say we need a PR, can we just use a Dayton DSA175-8 instead of a PR and get the same performance if we remove the magnet?
Or the other way around: can we use a cheap woofer, remove the magnet and voicecoil and it will act with the same Qms / Vas when used as a PR?

Is my logic incorrect that removing the VC shouldnt influence Qms and Vas at all? I can only imagine that Qms would increase slightly because some eddy currents could be removed when the VC + former dont have a magnet fields around them.
Could this also increase Vas as it results in less "breaking" while moving?

Hi all
Any info out there on how to calculate a multitap autoformer for use as a volume control?
The only thing I have come across is this from member Abraxalito
https://www.diyaudio.com/community/...phones-and-potentially-volume-control.386375/

I would like to wind one with a few steps just to see how it behaves.
Say 10steps. 2dB/step.
Rsource~1kOhm. Rload~10kOhm. Vin~5Vpp.

George

Hello everyone!


My name is [tu nombre si querés agregarlo], I'm from Argentina, and I'm very passionate about music and high-quality audio.


I'm currently studying Civil Engineering, and I'm also a certified electromechanical technician. That background has always drawn me to the physical side of sound—how speakers actually generate audio, how the components interact, and how design choices shape the final listening experience.


I've joined this forum because I want to design and build my very first loudspeakers, and I’m not just looking for a quick result. I really want to understand the “why” behind every component, every design step, and how each decision influences the sound.


I'm here to learn as much as I can and hopefully share my progress as I go.
Looking forward to connecting with this amazing community and growing in the DIY audio world!


Thanks for having me 🙌

please remove heading look at a utracer 🙂 just testing the waters to see if anyone wants to Sell with thier etracer?

Regards
Frank

I have developed a new 5.25in 2 way bookshelf speaker to go with the Vera-Link TWS Bluetooth amp. It’s a vented 2 way bass reflex design superbly finished in rosewood veneer and equipped with a custom voiced crossover using quality components (film caps and heavy inductors, and premium wire wound resistors). The woofer is a treated paper cone with a large motor and the tweeter is a 25mm soft dome with low distortion and a smooth silky response. The voicing is similar to my other speakers but the crossover is lower at 1500kHz and asymmetric filter slopes with all positive phase for realistic transients. I would say that the speakers have a punchy bass and a delightfully fun and musical sound signature. I have put several of my playlists through them and it all sounds great.

Speaker Dimensions: 17cm W x 24cm D x 30cm H

This was early crossover development with P2P Wago connectors:


I’m going with the all film cap crossover on the right. The one with the bipolar cap on left was just a sample for grins.




Here is the assembled speaker with the Vera-Link amps installed:


Setup in my bedroom (amp on dresser not being used):


The Vanguard Scout is a super sounding and beautiful looking speaker and will be offered at only $299 a pair. But if you buy it with the Vera-Link TWS Bluetooth amps together, the introductory bundle price is only $449.

Summary of Vanguard Scout:

The Vanguard Scout is a compact 2 way bass reflex speaker with a 5.25in treated paper cone woofer and a 25mm silk dome tweeter in superbly crafted rosewood veneer cabinet with a satin finish. What makes the Scout special is the crossover and how it is voiced to provide a smooth presentation with pinpoint imaging and a wide soundstage. The crossover uses high quality custom inductors and film capacitors typically seen on speakers costing 10x the price.

The crossover is a unique asymmetric topology that produces crisp and accurate percussion. The bass extension is deep for its size with a 60Hz -6dB point. The silk dome tweeter provides resolving highs while maintaining a smooth sound that is low in distortion. The treated paper cone woofer has a natural and lively sound with a slightly warm midrange that’s perfect for vocals. The balance and voicing of the Vanguard Scout is optimized for non fatiguing listening pleasure with all genres of music.

This speaker is the perfect introduction into great sound. Paired with the VeraLink TWS Bluetooth amplifier, it provides a complete music system - simply add your smartphone or other streaming decide with Bluetooth connectivity such as an Amazon Dot (Alexa) which enables multi-room playback capability.

To answer various instigations from forum members in the polemic of 'does THD..' I re-open this subject by submitting samples of audio recorded through the ADC of the Emu0404 to try to hear any differences in the various outputs of :
1. Dac of computer
2. Dac Ak4396 through ecc88 tube of Broskie unbalancer
3. Through Ak4396 + 6BL7 8 Watt tube amp.
4. Through Ak4396 + SS JLH modified amplifier
5. Through computer + SS JLH modified amplifier

Everything will be done at optimal levels for fairness and quality, (amps same power, dacs same output voltage, ADC same gain)

I am back again with the same amplifier, my lovely Xtant X604.
Last time I was able to recover the functionality with your help (water leak). Now I discovered that my front left tweeter is not working and making strange sound (I am bi-amping the front end). So I popped the cover off, inspected for water leaks - didn't find any but found 2 burned resistors. One is R111, the other one has no reference designator but since it sits between R108 and R110 it is likely R109. Also did a search before making this post and found the schematic for X603 posted by Perry Barin. Wonder if Perry or someone else has the same schematic without additional markings written over it. Perry was wonderful helping me fix the amp last time I had a short due to water leak that formed crater in pcb (2021). Will try to dig into this tomorrow.

I need Texas Instruments Transistor TI 1121 Datasheet。
I was given a couple of Texas Instruments transistors, TI 1121,does anyone have a datasheet, thanks!

Looking to purchase a pair of 1500AL or 1501AL frames (empty baskets).

I'm located in Los Angeles.

In this thread we can focus on the gimmicks of loudspeaker design. I see this thread as a place to point out potential Gimmicks of popular brands/models, to be dissected for the sake of clarity. There is only so much that can be done with modern loudspeaker design... I bet after a while the older ones of us have heard or seem it all. It is refreshing when something new comes along but it is disheartening when something is passed off as new, different, or legit when in actuality it is a load of BS. Maybe discussing these things can be a sort of therapy as we watch the world burn.

To start off, I present This..... I hypothesize diffraction from the skinny slots/groove in termination of the waveguide... desireable or even on purpose, unknown..... Laminar air flow? Skepticism draws near.... Reduces distortion? Why is there a distortion problem in the first place?

"an unusually complex flower-shaped waveguide to improve dispersion."

I was shocked to find that in just a few days it arrived from Japan, considering the times we live in. Thank you Victor for getting it processed and shipped so quickly.

I am taking my time with this build and just enjoying it bit by bit. For those that have assembled the TU-8600, this is very similar. For those that have never, it is really simple as long as you follow the instructions in the very detailed manual. Please dont ask me for copy of manual or circuit.

I will say that I did struggle a little locating parts. Some resistors are not bagged according to their values. I also find it difficult to distinguish some of the colors, but thats why you have a DMM right? If you cannot find a particular part, look in other bags that might not be so obvious. This is just nitpicking and not an issue really.

This 1st pic shows 3 layers of packing. Impressive !!!! The outside box was almost pristine. 2nd & 3rd pic shows just how beautiful the PCB's are. I was telling Victor, I really didnt want to touch them because they were so nice 🙂 You also have to "break" off about 8 pieces that had me nervous. I lost count but pretty sure I had to sandpaper about 40 perforations There are 2 rectangular sections in the main pcb that need to break off and this I believe is for the caps.

Pic 4 is the speaker connectors, 5 & 6 show the headphone jack.

Even though parts are of good quality I am going to swap out the 9pin tube sockets for ceramics if I have them around.

The end goal here is to compare my mostly stock 8600S with this stock 8900 listening to Cossor 300B at first and then will switch over to 2A3 when they arrive from Victor.

I am going to give it a rest for the night and soak in the fun I had.

Hi everyone,

I am hoping to implement one of the solutions presented on this thread :




I have entered the first circuit into EasyEDA (standard Windows install version 5.4.46) because I have all the parts already.

In the second photo from the thread we see the simulation working as desired, with 3.6V for one second and then dropping, however, in my EasyEDA, the simulation does not turn on the LED and the voltage at output is 0.6V.

Can anyone see the problem? What must I add to for it work?
I tried adding a 1M resistor in parallel with C1, and then the LED does light up and we have 1.86V on the output, but it never drops.

Thank you for any help.

EJ

Hi, I had the RCA cable from my CDJ disconnected and just hanging about but got a shock when my arm touched the RCA and my newly built diy amp simultaneously.

I measured it with my multimeter and found that there is roughly 200V AC between the RCA and the chassis. I don’t really understand this consider that both are at very low voltages when I measure them to ground.

The amplifier has been properly earthed with the paint stripped away and locking washers to dig into chassis.

Is this unusual behaviour or should I just move the rca cable?

Edit:
I should clarify the RCA was not connected to the amp only to the CDJ.

...the HD stands for HooDoo, if I'm not mistaken. I have two, maybe three of these:

Free with any purchase from my other listings!
First to ask gets them. Consolation prize, your choice two free pairs of binding posts!!

Cheers and happy shopping!

AWEDIO

This is my take on the well-known Elektor PreConsonant phono stage. It has been fully built and tested; in fact, I am using it as my main phono stage at the moment. I have finally got around to correcting small silkscreen errors on the PCB, and now I feel comfortable sharing it with the community.

This is what an assembled PCB looks like:



Thanks to @vsmusic for inspiration, it was his post about the PreConsonant over at Lenco Heaven that started my addiction to DIY phono stages, and I even learned how to use KiCAD to design my own PCBs.

I also designed a very simple discrete voltage regulator to go with it. It probably does not perform as well as common 3-pin regulator ICs, but I wanted to use a 24V AC wall-wart that has very poor load regulation. Its no-load voltage is almost 30V, which after rectification exceeds the maximum input voltage of something like a 7824 or LM317. In use I cannot detect any PSU-related hum even with my ear right against the speaker.

Gerbers, BOM and build notes are available here: https://github.com/SpinningVinyl/PreConsonant2021

Gerbers and BOM for the PSU: https://github.com/SpinningVinyl/PreConsonantPSU

Hello, just a question in the community,
I have old Castle Trent Speakers (Gold Edition) and for my impression the tweeters are not working anymore. I have also old Castle Durham II Speakers. The tweeters look exactly like the tweeters for the Trent-model. I this true? Are they similar and can I use them for the Trent with the same brilliant results than the regular Trent-Tweeters?
Thanks for further informations,
Martin Napp

Hi everyone,
This project turned out to be quick, straightforward, and with a great outcome—so I figured it was worth sharing.

These desktop speakers deliver a clean, confident sound. They handle plenty of power, are solidly built, and easy to put together. The goal was to upgrade the speakers I use with my PC (driven by a TPA3116 amp) for listening to music, voice, and video—so clarity was key. That said, with a bit of EQ, they’re also more than capable of livening up a party.

I went with Faital drivers, partly because they’re readily available here in Buenos Aires, but also because they come with reliable and comprehensive specs.

I kept the crossover design simple—a first-order Butterworth filter set at 1kHz—and it did the trick. Of course, you can always tweak the resistor values if you want to shape the top end a bit more.

Update (5/21/2020): My Plans for XKi W5-2143 here.

Update (4/17/2019): xrk971's W5-2143 XKi (more info here):


Videos here: https://www.diyaudio.com/forums/ful...tio-karlson-6th-bandpass-127.html#post6689070

XKi W5-2143 basic design here.. It is very important to follow all the instructions in previous link showing internal build details regarding use of melamine foam damping pads and felt and foamcore on the backside of the aperture.
143 here.

Update (3/23/16): Srednivashtar's wonderful dual PA130-8 XKi






What's the deal with a Karlson aperture in front of the driver? Won't that mess up the polar dispersion? That's a great question, and no. The aperture actually improves the uniformity of the polar response compared to the bare faced driver:



This thread found its beginnings here: A Speaker that Kicks Butt in Large Spaces - Page 66 - diyAudio. The finding was interesting enough that I decided to put it on its own here.

I will recap:

Properly scaling the Karlson K15 cabinet to work with smaller drivers has been an elusive goal for over 50 years. If you are at all familiar with the K15, you know that the moment it is scaled below a 12/15 scale, the bass extension suffers. The cabinet excels at efficiently controlling cone motion and channeling what little motion there is into high SPL levels, albeit, with some warts in the way of the famous Karlson "W" dips and peaks in the mid-bass region. Nonetheless, the speaker sounds very good and has a devoted following.

I recently have been working on developing 6th order bandpass subwoofers over in the subwoofer forum, especially slot-loaded push-pull bandpass subs. This alignment is very good at controlling cone motion and in many ways reminded me of the topology of a K15. So I got to thinking that I could develop a K15 style cabinet for any size driver, if they satisfy some basic T/S parameters needed for a 6th order bandpass box (moderate to low Qts, low Vas, strong motor, high sensitivity, etc.). I would design the new box from the ground up, or as they say, "from the beginning". The "i" is for ab initio, or from the beginning. I have figured out how to design a new type of "K" box with deep bass, good cone control, for any size driver with appropriate T/S parameters. There is no scaling of the K15 design involved, and it begins with the design of a 6th order bandpass alignment optimized for bass extension, flat response, and good control of cone motion, all properties that a 6th order bandpass alignment is known for. The difference is that the output port is simply a Karlson aperture of appropriate cross sectional area, and the chambers are designed with angles to avoid rectangular volumes that may have resonance modes.

As a test case, I designed a box that can reach 50Hz using a nominal 3.5in driver - the Dayton RS100P-4 (paper cone). This driver has a suitable moderate Qts to allow fb to set below fs and has good xmax of 4mm and a relatively powerful motor. The 6th order bandpass design was a 4.0 liter rear chamber and 1.0 liter front chamber with a 0.5in x 5.0in x 9.0in long vent, and a front chamber vent consisting of a 5in dia aperture.

I converted these volumes and vent dimensions into a box that has internal dimensions of 5in wide x 9.0in tall x 7.5in deep which then provides the correct volumes once the vent volume and driver volumes are subtracted. The front K-aperture is sized to have the same cross sectional area as a 5in dia hole, which was approximated by the area of a triangle that is 5in wide x 7in high, accounting for the curvature and offsets near the bottom.

The box design looks like this:



Here is a photo of the inside during construction showing the bracing and folded vent arrangement leading to the top of the front chamber (although not ahown, there is a piece of open cell foam on the bottom and I put a wad of pink fiberglass in the main large volume to damp the HF's from reflecting back onto the rear side of the cone):



Here is the completed speaker - still retains the look of a very small K15:



And here is the measured frequency response about 0.5m away along the axis of the driver centerline - it has the characteristic Karlson "W" dips and a falloff near the bandpass followed by the direct radiator output which lets it reach up to the HF limit of the driver (about 14kHz in this case). The measured f3 is 51Hz! An amazing concept for anyone who has ever tried to scale a K15 down will realize. Predicted max SPL at 4mm xmax is 98dB in 2pi space:



How does it sound? Very nice - sound clips attached below. Dispersion was very good as evidenced by the polar data showing very little variation in the response from 0 deg to 45 deg (or 90 deg full cone, and even out to 60 deg the variations are quite small). This is one of the biggest advantages of the Karlson aperture is a uniform polar response:



The transients are also clean as you can see from the measured impulse response. Furthermore, because the polar response is so uniform, the impulse response is also uniform along different angles. Many open face speakers will exhibit vastly different impulse responses because they have beaming or cone breakup modes that are angle dependent.

Here are the IR's for 0 deg to 45 deg (note the similarities from 0 deg to 45 deg):









This is a tiny speaker with a tiny driver, but it sounds quite big. Now, the neat thing about this methodology is that if a 3.5in driver can hit 51Hz, a 6.5in or 8in can probably do 40Hz. This can also be used for a sub woofer with a good pro audio 12in driver like the Faital Pro 12HP1030 and achieve 120dB SPL and mid 30Hz...

I applied a -24dB/oct high pass filter at 47 Hz to reduce cone excursion and some EQ to see if we can't make the response less bumpy. Here is the result of the HPF and EQ:



Here is the impulse response after the EQ has been applied - a little cleaner:



Here is the harmonic distortion - a lot of this is the result of the foam core cabinet vibrating. CLD can knock this down quite a bit but I have not done that yet:



If you are interested in this speaker and would like to design a box around your favorite driver, follow along and I will detail the process and methodology for designing the XKi for your driver.

Briefly, the process starts with a design of a quasi 6th order band pass box with your favorite driver, but with these guidelines:

1. Set the rear chamber volume to front chamber volume ratio at 4:1
2. Set the output vent to have a cross sectional area equal to at least 2x Sd if you plan on using full range drivers
3. Using a quasi 6th order bandpass simulation program (Akabak, Bassbox, etc) adjust the vent length and chamber total volume to provide the optimum balance of bass extension, SPL output, and flat response.

Akabak script for 6th order band pass is available here: XKi - X's ab initio Karlson 6th Order Bandpass - Page 16 - diyAudio

4. Convert the volumes and vent length to a box with a total volume equal to 5x the front chamber volume PLUS the driver magnet/basket/cone volume and the vent volume
5. Set the width of the cabinet based on driver bezel width plus an inch or so of margin, set the height at an aesthetically pleasing ratio (golden ratio is good), Fibonacci, etc.
6. Calculate the depth based on known volume and height and width
7. Calculate the front chamber volume using the area of a triangle - this calculates the setback of the angled V in the front chamber.
8. Make the vent a channel vent leading from the top to the back and wrapping down. Note that the final build tends to have a deeper tuning than predicted due to the additional losses in the narrow aspect vent walls, so you may want to reduce the vent length by about 15% or so in the build.

Edit Jan 25, 2015: effects of EQ, high pass filter, and aluminum vs paper cone - aluminum cone seems to have more bass.


Edit Feb 19, 2019: Plans for XKI with PA130-8 by Thermcul


xrk971's As-Built XKi for W5-2143:

For sale: Audio Note DAC 2.1 Signature output board with Black Gate FK capacitors, Audio Note copper capacitors, Audio Note tantalum resistors, Audio Note ceramic tube sockets. All soldered with Audio Note silver solder. In perfect working order, sounds amazing.

My apologies ahead of time if this post isn't appropriate, but I was wondering if any First Watt F7 owners (or the DIY variants) know if it will pair well with a Schiit Freya+? As usual my interweb searches yield both positive and negative views... and almost every most other places like reddit tell me to try the diyaudio forums. 🙂

TIA!

I've lost count how many times this question keeps getting asked.

PLEASE USE THESE DEVICES

Linear Systems Matched LSJ74/LSK170 JFET pairs (Grade B) – diyAudio Store

J74/J74 Stereo Differential Kit – diyAudio Store

Linear Systems LSK170 Ultra Low Noise Single N-Channel JFET (8 Pieces) – diyAudio Store

Linear Systems LSJ74 Ultra Low Noise Single P-Channel JFET (8 Pieces) – diyAudio Store

Hi everybody,

I used to be an audio electronics hobbyist in the mid 70s, then I gave up at the beginning of the 80s. Now I’m trying to take up again, possibly with a better knowledge, also thanks to the Internet. My main interest is vintage audio (hi-fi, music instruments, amps & preapms etc.). I found a lot of information and a very supportive community here so, I'm glad to be on board.

Hi, please help me with Sony ST SA5ES Front End tuner repair.

Edit July 28, 2023: here are the schematics, BOM, and info on the single rail SLB. https://www.diyaudio.com/community/...x-class-a-power-supply-gb.336479/post-5782376

Edit Jan 23, 2020: Connection diagram for single trafo and dual rail SLB with M2X amp
The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB

Edit June 16, 2019: Error on Q5 orientation on Single Rail (SR) board. Please install Q5, BD139 with pin 1 to the square pad (as customary) but this will have front of part in contact with HS1. Ok to use smaller stamped aluminum finned heatsink here for back mounting. More info here:
The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB

Edit June 12, 2019: in an effort to reduce my logistical overhead and efforts to pack and ship as track - I will be handling the GB2 via my Etsy shop. The SLB can be found here:
Smooth Like Buttah SLB Class A PSU | Etsy

I have been working on the development of a new power supply for Class A amps that really is quite a big leap forward from current designs used for so long. It utilizes an active bridge rectifier provided by the LT4320 and MOSFETs, followed by a precisely engineered CRC filter designed to match the load, and finally followed by a capacitance multiplier. The advantages that such a power supply will have include:

1. Almost no heat dissipation or loss through the rectifier
2. Improved voltage headroom since no 0.6v drop across the silicon rectifiers
3. Smoother inherent ripple from the rectifier since switching is active and time phased to occur at zero crossing
4. More compact since fewer and smaller bulk caps are needed
5. Lower overall cost since fewer large bulk caps are used (and we all know this is one of the most expensive parts of a Class A amp aside from the case)
6. Most importantly, improved performance relative to a traditional CRC supply with lower ripple and higher current capability.
7. The SLB provides a smooth and slower (1 second) ramp that may reduce speaker turn on thump. However, current in rush from the transformer being turned on is not prevented and a suitable soft start circuit such as the Soft as a Feather Pillow (SFP) SSR soft start can be used for a soft start.

You may say that the downside is that it’s more complicated - but for those of you going through the trouble of using 8 x MUR TO220 diodes with their requisite heatsink, insulator pad, bolt, screw, insulated bushing, snubber film cap, and tight spacing that makes assembly difficult - I am not so sure anymore.

Here is a photo of a single rail SLB portion of the amp (we integrated it as part of the amp for testing). You can see how small it is when using SMT variant of the active MOSFETs (mounted underside). Those are 15,000uF 50v bulk capacitors. Compare that to how usual Class A CRC or CRCRC supplies are using 22,000uF or 33,000uF caps. The large 3pin Molex connector allows us to place the cap Mx pass transistor anywhere we like and allows snappy assembly/disassembly from the chassis or heatsink:



Jhofland, Aksa, Vunce and myself have been working on a single rail prototype of this PSU which we are calling the SLB. The name says it all - Smooth Like Butter. Jhofland has been leading the layout and electrical design, Vunce and myself are doing the verification builds and testing of the performance and listening to the resulting music, and Aksa has been instrumental in providing insight and guidance, plus overal cap Mx topology design. It’s been a great collaboration and I feel that we have arrived at something really special and useful.

The design requirement was that it can flow 5 or more amps and have ripple in the single mV range (we are looking for about -60dB to -70dB ripple rejection) with a simple hookup of a secondaries from a power trafo. You then get clean mV ripple (sine like and not sawtooth) with a small adjustable output voltage range based on how much drop you want across the cap multiplier.

Regarding capacitance multipliers, we are testing 3 different topologies: Darlington, LTP differential (similar to the MrEvil design), and a new complementary feedback (CFP) pair with BJT’s. Work is on going but we are getting close to a downselect.

Here is the measured ripple (1.4mV rms) from the Darlington cap Mx with 4.35A load (37.5vdc output) with an 8ohm resistive load:


Under a real SE Class A amplifier load, the ripple is a bit higher at about 6mV rms with the Darlington topology, but still very respectable given a 4.35A current:


Our simulations show that the CFP topology should be even better. The LTP differential topology will be tested soon (tonight perhaps).

I thought it is now a good time to share the initial developments to get everyone ready for the SLB PSU. I hope that this compact little supply will be a useful new tool in your toolbox of Class A amps. It certainly provides some of the cleanest power Inhabe ever measured or heard.

Edit - here is layout:


Update May 5, 2019: Verification build test with 4.4A and 35.4v out and 3.1v drop gives about 1mVrms ripple with the SLB (with R17/18 replaced by jumper):


Here is the SLB vero build (v1):



Update May 6, 2019: Schematic and BOM of v2 (May 3, 2019) Production version of SLB here.. Pricing of SLB is $22.50ea (2mm thick FRP, 2oz Cu, ENIG finish, blue mask):


Edit May 6, 2019: Here is the SLB-SR (single rail version). BOM and Schematics here. Pricing on SLB-SR is $18ea (also 2mm thick FRP, 2oz Cu, ENIG finish, blue mask):


Edit May 9, 2019: Here is the pereformance of the SLB in single rail form as used on an actual SE Class A amp with 37.4v rail and 4A current. The top red trace is for a 10R value on R117 and bottom yellow one is 1.5R for R117:


Edit May 23. 2019: Production PCBs arrived.
Dual Rail


Single Rail


Edit June 5, 2019: Md_Stryker made a Mouser shopping vart/BOM for SLB v1.2 here. Please do not modify it - copy to your own project first!
The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB

Edit Jan 23, 2020:
Connection Digram for a No-Hum M2X PSU with SLB and single trafo:


Connection Diagram for no-hum Alpha Nirvana:

Hello
I am selling a complete PCB for this project:
https://tolisdiy.com/2021/01/30/audio-measurement-pre-amplifier-part-5-updated-ver1-1/
The price for the complete set is 65 EUR plus shipping.

I'm going in another direction with my audio system so I'm offering my custom Audio Note Kits (ANK) Dac 2.1 for sale.
Info about the kit: https://ankaudiokits.com/product/dac-2-1/

I bought the kit from hificollective uk.

It's the "B" version with I/V transformers.
Mains transformer and choke are custom wound by AE Europe.
I added an usb input with the Singxer F1 XMOS usb to s/pdif interface.

Most caps and resistors are Audio Note, Jensen and Takman,
Some very nice NOS tubes (Raytheon 6X5WGT, Siemens ECL 82 and Philips MiniWatt E188CC SQ). I have some more tubes for the dac that I'm willing to add.
Vandamme cabling.
On/off switching is through a Hypex sofstart module


All this is wrapped in a self made solid padouk wood case with aluminium face and back plates from Modushop.
I also have new, bare pcb's for the M2x power supply and the dac board.
Manuals and schematics available.

Building and designing the unit was the biggest joy for me and it's been in my system for quite a while, but now i've moved on to different projects and it's time to create some space on my bench.

There is a slight hum, probably a ground issue.

Check out the pics and when interested, make me a fair offer.
I'm in the Netherlands. Willing to ship at buyers cost & risk.

Hello,

I'm working on a device that needs to switch between two AES3 audio channels. For this purpose, I’m considering using the TS5A22362 analog multiplexer.

According to the datasheet, the TS5A22362 supports up to 5.5 Vpp signals, while AES3 signals are typically defined as 2–7 Vpp. Given this, is it still a good idea to use this part, or would you recommend a different solution? If it is fine, should i supply 5V to VDD for the best performance? Will this design be reliable for all types of audio equipment?

I’ve also heard that using relays with gold-plated contacts might offer better performance in terms of jitter. Could you please advise on this?

Hi guys,
Recently I've been trying to fix the yamaha cr-220:
Please see schematic

Blown transistors are:
TR712 (2SA844)
TR716 (2SC1175)
TR717 (2SA659)
I've replaced them with European BC557 and BC547.
I think of replacing also the complimentary drivers (TR715, TR718 - marked 818 by mistake in the schematic diag.)
Been testing it for several hours and the amp seems work really nice at the moment.

I'm wondering if maybe there are better replacements for this kind of amp?
Im thinking:

KSA992/KSC1845 OR
KSA1013/KSC2383

1) Should I replace the complimentary driver transistors even though everythig seems to sound fine?
2) Should I use any of the transistors above or should I look at other options? If so, What are they?
3) Any opinions regarding the amp in general or this specific repair?

Thanks,
Liquias.

Hi Everyone,

I'm Tom from Flanders, Belgium and started an audio Hobby about a year ago. Started with the idea of building a simple full range speaker. I have a background in electronics but absolutely no woodworking skills. Working on an MTM at the moment and a bluetooth speaker box and still trying to find out how to properly use my palm router. Love Rock and classical music and dream about building a 5.1 home cinema experience.

My audio setup at the moment:
ARCAM AVR amplifier
ARCAM CD player
WIIM mini
SU-1 DAC
SB ACoustics phono player
FOSI audio preamp
B&w 607 front speakers
Pro-ject desktop speakers
a bunch of dayton audio components waiting to become speakers

I am an electronics enthusiast from the Netherlands and I love repairing old vintage tube gear. I have plenty of questions and stuff to learn about repairing this stuff. I am going to start my first year soon in eletrical engineering.

Cheers!

Hi all. I'm in the process of building my first crossover and before I go and start laying out and drilling, I was hoping that someone could confirm if I've wired this properly per the schematic (done by Solen). I know the arrangement of the parts is way wrong but I just want to confirm that my tie points are correct.

Since I'll be fine tuning values and upgrading caps, I'll likely use terminal strips like Troels Graveson to facilitate easy swapping. Like I said, this is my first build, so would be so grateful for a confirmation. Thanks

Hi there - I'm sourcing the material for the top plate of the chassis for my Tubelab SSE build. On the wiring diagram page, it says to make sure that "all metal objects (transformers, supplemental cap, choke, volume control, etc) should have a good paint free contact with the chassis". If I use something like anodised aluminum, does this mean I have to scrape away the anodised layer so that the parts make solid contact? Or is the anodised aluminum still conductive enough to ground the parts?

I recently did some measurements on three contemporary output transformers aimed for use in the Williamson amp.

The measurements provide a look at the primary winding inductance, as well as impedance and output frequency response over a 2Hz to 95kHz range (the limit of my USB soundcard) using REW software.

The output transformers were the venerable Partridge WWFB, plus two Australian made OPTs that came out in early 1948 to meet the Williamson diy demand (Ferguson OP25 and Red Line AF8).
https://www.dalmura.com.au/static/Partridge%20datasheets.pdf
https://www.dalmura.com.au/static/FergusonFeb1948.pdf
https://www.dalmura.com.au/static/Pages%20from%20Australasian-Radio-World-1948-06.pdf

The measurements are not for the OPT in a Williamson amp, but just of the OPT itself, but do provide an insight in to how a particular OPT could be compared to other OPT's, and to support how such an OPT could be integrated in to a Williamson amp and the required low and high frequency response tailoring that may be needed for unconditional stability.

Aspects that I thought were quite interesting were the noticeable response differences when choosing a speaker impedance setting, and the variation of measured inductance due to a variety of influences.

The write-up is linked below, and may change over time if I come across other contemporary OPT's or add to the measurements made or correct mistakes/misunderstandings. I must admit that the 'modern' soundcard/REW combination is a joy to use on a diy bench, and can but wait and hope for a new generation of soundcards that bring sub-1Hz to circa 190kHz bandwidth capability, as that would provide a nice addition to an OPT's performance assessment.
https://www.dalmura.com.au/static/Williamson%20output%20transformer%20measurements.pdf

I seem to remember that background music in movies used to be either pleasant or sometimes suspenseful to match the scene, but never annoying. Now, however, it seems that movies are being made with lots of irritating types of background music.

On top of that they will sometimes suddenly increase the volume to very high levels and then back down again. So, if you decrease the volume to prevent being irritated from the very loud music, then you have to turn it back up again to hear the dialog. As a result, I constantly have to adjust and readjust the sound volume throughout the movie.

It this just me, or do others have the same issue.

A guy sell to me 2 of the title subs with broken amps.when connect to power outlet there is no signal of life no leds on nothing.I have ready check the fuse bridge diodes and output devices and all measures fine.Check optocoupler ok.I suspect one of the 4 chips.Any ideas?Thanks you in advance.

Hello,

I have a problem with a really high frequency noise at the output of my Marantz M-CR603, a ~300kHz noise of ~1Vpp : (I precise the amp with loaded with an 8Ohm dummy load)

(see out_noise_1.jpg, and out_noise_2.jpg is the same noise but with a different temporal scale - we can see a slower other oscillations superposed on the other)

The amp features an SMPS power supply, and the amplification is digital, here the amplification scheme :

(see amplifier scheme.png)

Now I have the feeling the noise is not normal. It is quite high in amplitude and I fear for my speaker, from what I have read on internet about high frequency noise and tweeter blowing. So I was looking for a culprit in the circuit. I first checked the power supply. There are two supply here, a +12V and a +32V. The +12V is not noisy at all. However, the +32V is really noisy (1Mhz noise). Here a picture of the rail with my scope AC coupled :

( see +32_noise.jpg)

I thought it may have been one of the SMPS capacitor (I already found some bad on it, that I've changed), so I've changed all of them with new one, but with no improvements.
The supply comes from the SMPS board to the main board through CN61 (see filtering_1.png).

->Now on the schematics, I can see some small filtering cap at the entry on the board (see filtering_1.png), and some other at the digital amp chip (see filtering_2.png). The electrolytics are good (there are one per channel of 3300) and the little ones are film caps, nicely soldered.
So I guess all caps are good doing their job

-> Now, I see inductance in serie with the outputs, but both right and left channels of both A and B speaker output are noisy so I don't suspect a problem in a particular component bur rather in the supply.

-> So I am lost ! If supply is supposed to be good (but is it with a 1MHz noise ..?) and the signals paths are good, where is the problem coming from ? (but is there really a problem with the 1V, 300kHz noise at the speaker output ?)

Any ideas would be welcome !
Thanks

once installed it is very simple and intuitive, but when I go to create the .zma file, it does not create/save it. maybe I'm doing something wrong...
so I installed VituxCAD and repeated the simulation of the mid-wwofer with the values used in the two-way.
I'm shocked!

If I wanted to measure the primary impedance of an output transformer from a tube amp can I load the secondary with the specified load resistor and use the DATS V3 on the primary to give me the impedance or is there a better way?

I've got a transformer that has a 4, 8 and 16 ohm tap. Anyways the 4 ohm tap is supposed to be the center of the winding and I should get equal voltages from the 4 ohm tap and ground and the 4 ohm tap and the 16 ohm tap. The 16 ohm tap has a slightly higher output voltage than the 4 ohm tap.

60Hz sinewave on primary winding.

4 ohm tap to ground 118mVrms
16 ohm tap to 4 ohm tap 127mVrms

Need to measure the primary impedance with a 4 ohm load and then a 16 ohm load so that I can determine if the 16 ohm tap is greater than 16 ohms or if the 4 ohm tap is less than 4 ohms or if it's a combination of both.

Hello! I'm new to the forum and I'm hoping someone may be able to help me. I have been trying car audio amp repair but I'm lost at the moment.
I have 2 Monoblocks with different issues.

1. Concrete Audio 2k
Protect mode at 13v+ although rated up to 16v
At 12v, gain all the way down, no input, and with a speaker connected (I have tried a few different speakers and all do the same), starts normally then makes a loud pop every 3-4 seconds and flashes protect light
Does not happen with nothing connected (12v), audible click, power light and fans running, no protect

2. Soundstream XXX-6500D
Turns on with power LED and no protect, fans run, but no output to speaker terminals
Tried multiple speakers, tested with multimeter (any settings to try? I may not have tried correct setting), multiple RCAs, but only tested with 12v. This specific one has ratings at 13.5v, 14.4, and 16v but my other XXX-6500D has at 12v-16v.
Would 12v vs 13.5v cause this?

As of right now I would prefer to get the Soundstream working sooner than the Concrete Audio amp as I would like to install the Soundstream in my setup

I have a variable power supply that can go up to 30v and 3amps, a component tester, multimeter, and an oscilloscope but I am a bit confused on where to probe, what settings I should have, and where I should ground the probe or if I shouldn't use the ground lead.

Any help is appreciated and if there is anything someone would like me to send pictures of I can do so.

Good to be on the forum, thank you very much. I am from south Africa and a keen hifi enthusiast. I have fiddled with and built several items. It all started in the 80's with the Linsey Hood amp. Still have some parts for it! It chewed up a pair of Leak Sandwich 300 speakers when I got too enthuastic with it. That kicked off some speaker building projects, mainly SEAS based.

PACTF，Polymer cured Amorphous Carbon Thick Film resistor.

Compared with the first generation "gold" carbon resistor, the principle remains unchanged, but the process becomes more pocket-sized.

Try to mix nano silicon dioxide into the resistive substance according to the original formula, and the resistance value is obviously increased. Connect this resistor to 220 volts, and the heating power is about 1 watt. After more than ten seconds, the resistance obviously heats up, and the resistance value has an obvious trend of upward change(+5%).

In addition, the resistance value of this kind of resistor will gradually and slowly decrease to a stable value within several weeks at room temperature, which may be related to stress and so on.

However, the mechanical strength of the resistor paste is enhanced by adding silicon dioxide, and a higher proportion of silicon dioxide filler is used in the shell to reduce the effect of stress on the resistor film, so the resistance value decreases very little. After just maded 48.9 kΩ, the resistance value is stable at 48.4 kΩ after 45 days. Has preliminary practical value.

Mark the resistor with a water-based pen, and coat it with insulating paint after drying, which will make it look beautiful and the mark will not be erased easily.

It is welded in the circuit of the electron tube radio and works normally. Although it is a amateur miniaturized version, the size is still much larger than that of the industry finished product.

ANY info would be great:
What i have sourced: They were designed by John Wright and built in electrical shop (Transmission Electronics) at 495/9 Oxford Road Reading Berks. The company was then called Transmission Electronics Ltd, and the products were badged IMF (Note this model in photos does not carry the IMF badge) Eventually the joint venture folded as the shop owner decided it wasn’t his “thing” anymore, and the IMF side went off I think around mid 1973 to High Wycombe and founded IMF Electronics Ltd. The company fully became IMF.

I can't find much info on this model.
What i do know is their made by Transmission Electronics Ltd. which later became IMF Electronics.
1×Woofer Kef B139, (1973 sticker)
1×Passive Kef
1×KEF Tweeter
1×Celestion Mid
They are very well made.
Sound fantastic.

Here is a tapped horn design intended for pro sound reinforcement type applications, or any just plain old, really loud music apps that I started working on last July and finally finished the design back at the beginning of March. I worked on this in tandem with the Gjallerhorn. I decided to have the Gjallerhorn built first as it was a larger, more complicated, more expensive and risky design. Since it turned out so well I am feeling rather confident about this one. 😎 My goals with this design were true 30hz extension with solid useable output to the 25hz range. This is quite a bit lower than the majority of pro bass bins will really reach to despite their ratings. The increasing popularity of down tuned 5 and 6 string bass guitars, bass drops and the prevalance of DnB and Dubstep genres have started to ask for more power than ever from subs in the 25-35hz range. Along with this extension I wanted it to still be able to get quite loud and to retain decent sensitivity. I also decided to use an enclosure form of no larger than 36x36x24" which is large but not out of the ordinary for pro bass bins and comparable in total volume with many double 18" vented subs. A larger 45x45 type of cabinet like the Gjallerhorn or Labsub would've given better efficiency and higher output but these types of cabs are larger and heavier than I want to lug around very often. A pair of these should do most bars or small venues with no problem and 4 should do a good job in a mid sized venue. 2 will fit in the cargo hold of most medium sized suv's.

I already own a pair of B&C 21sw152-4 drivers and Danley has already used them in a couple of tapped horns so it was a no brainer to design around them.

Fast forwarding through about 9 months of design work and revisions here is what the final design will be. I will contract he same cabinet shop that built the Gjallerhorn cabs to do these as well. Unfortunately with everything else going on I don't have the time to build cabs this complicated myself anymore🙁. Besides I could never deliver the build quality that the professionals can.

BTW Thanks to Soho54 for being my sanity checker on this cab design.

Here is the HornResponse and Akabak input data for simulating the cab. This one was also designed in Akabak working backwards from the cabinet size and best fold that would fit in the cab and achieve the right low corner instead of the other way around. I have found this works much easier for me than coming up with a pretty simulation and trying to fold and cram it into a workable cabinet while maintaining the parameters. Once again I use Akabak since there were so many folds, different expansion rates and corners involved. Amazingly the much simpler HR simulation that approximates the final Akabak one is very close. The differences are there but quite small. Not worth worrying about for most people unless you are a stickler like me who is worried about accuracy to the nth degree. Anyway here are the inputs.



NOTE: If you wish to model 18" drivers in this cabinet you should change the value of VTC to 4000 and the ATC value to 1465

HR





Akabak script
|COMMENT: OTHORN B&C 21SW152-4 30hz TH 36"x36"x24" revised 030411 completion(Driver restricts horn by approximately 517cm2 at S32)



|========================================================================================================



|REQUIRED AKABAK SETTINGS:



|File > Preferences > Physical system constants:



|Sound velocity c = 344m/s

|Medium density rho = 1.205kg/m3



|Sum > Acoustic power:



|Frequency range = 10Hz to 20kHz

|Points = 533

|Input voltage = 1.86V rms

|Integration = 2Pi-sr

|Integration steps = 1 degree ... 1 degree

|Integration method = Cross



|========================================================================================================



Def_Const |

{

|Length, area and volume values converted to metres, square metres and cubic metres:



S1 = 20.397216e-4; |Horn segment 1 throat area (sq cm)
S2 = 400.79072e-4; |Horn segment 1 mouth area and horn segment 2 throat area (sq cm)
S3 = 480.93721e-4; |Horn segment 2 mouth area and horn segment 3 throat area (sq cm)
S4 = 490.40735e-4; |Horn segment 3 mouth area and horn segment 4 throat area (sq cm)
S5 = 499.87748e-4; |Horn segment 4 mouth area and horn segment 5 throat area (sq cm)
S6 = 503.41786e-4; |Horn segment 5 mouth area and horn segment 6 throat area (sq cm)
S7 = 752.67183e-4; |Horn segment 6 mouth area and horn segment 7 throat area (sq cm)
S8 = 525.374e-4; |Horn segment 7 mouth area and horn segment 8 throat area (sq cm)
S9 = 672.07369e-4; |Horn segment 8 mouth area and horn segment 9 throat area (sq cm)
S10 = 1003.4701e-4; |Horn segment 9 mouth area and horn segment 10 throat area (sq cm)
S11 = 706.47214e-4; |Horn segment 10 mouth area and horn segment 11 throat area (sq cm)
S12 = 710.68271e-4; |Horn segment 11 mouth area and horn segment 12 throat area (sq cm)
S13 = 1011.4833e-4; |Horn segment 12 mouth area and horn segment 13 throat area (sq cm)
S14 = 744.03216e-4; |Horn segment 13 mouth area and horn segment 14 throat area (sq cm)
S15 = 827.70445e-4; |Horn segment 14 mouth area and horn segment 15 throat area (sq cm)
S16 = 1148.9606e-4; |Horn segment 15 mouth area and horn segment 16 throat area (sq cm)
S17 = 850.19967e-4; |Horn segment 16 mouth area and horn segment 17 throat area (sq cm)
S18 = 852.58905e-4; |Horn segment 17 mouth area and horn segment 18 throat area (sq cm)
S19 = 1222.0554e-4; |Horn segment 18 mouth area and horn segment 19 throat area (sq cm)
S20 = 876.8326e-4; |Horn segment 19 mouth area and horn segment 20 throat area (sq cm)
S21 = 434.06586e-4; |Horn segment 20 mouth area and horn segment 21a throat area (sq cm)
S22 = 572.31875e-4; |Horn segment 21a mouth area and horn segment 22a throat area (sq cm)|
S23 = 1185.3696e-4; |Horn segment 22a mouth area and horn segment 23 throat area (sq cm)
S24 = 1724.8322e-4; |Horn segment 23 mouth area and horn segment 24 throat area (sq cm)
S25 = 1255.2883e-4; |Horn segment 24 mouth area and horn segment 25 throat area (sq cm)
S26 = 619.44195e-4; |Horn segment 25 mouth area and horn segment 26a throat area (sq cm)|
S27 = 680.54455e-4; |Horn segment 26a mouth area and horn segment 27a throat area (sq cm)|
S28 = 1400.7642e-4; |Horn segment 27a mouth area and horn segment 28 throat area (sq cm)
S29 = 2279.1994e-4; |Horn segment 28 mouth area and horn segment 29 throat area (sq cm)
S30 = 1799.9231e-4; |Horn segment 29 mouth area and horn segment 30 throat area (sq cm)
S31 = 1805.1536e-4; |Horn segment 30 mouth area and horn segment 31 throat area (sq cm)
S32 = 1411.3236e-4; |Horn segment 31 mouth area and horn segment 32 throat area (sq cm)/(1411.3236cm restricted by driver (estimated),1928.3236cm ignoring driver in path)
S33 = 2043.1017e-4; |Horn segment 32 mouth area and horn segment 33 throat area (sq cm)
S34 = 2057.0009e-4; |Horn segment 33 mouth area and horn segment 34 throat area (sq cm)
S35 = 2260.638e-4; |Horn segment 34 mouth area (sq cm)

L12 = 27.504644e-2; |Horn segment 1 axial length (cm)
L23 = 27.258518e-2; |Horn segment 2 axial length (cm)
L34 = 3.070098e-2; |Horn segment 3 axial length (cm)
L45 = 3.355594e-2; |Horn segment 4 axial length (cm)
L56 = 1.203198e-2; |Horn segment 5 axial length (cm)
L67 = 3.625088e-2; |Horn segment 6 axial length (cm)
L78 = 3.781298e-2; |Horn segment 7 axial length (cm)
L89 = 41.853612e-2; |Horn segment 8 axial length (cm)
L910 = 4.81838e-2; |Horn segment 9 axial length (cm)
L1011 = 5.029708e-2; |Horn segment 10 axial length (cm)
L1112 = 1.20142e-2; |Horn segment 11 axial length (cm)
L1213 = 4.740656e-2; |Horn segment 12 axial length (cm)
L1314 = 4.877562e-2; |Horn segment 13 axial length (cm)
L1415 = 37.930582e-2; |Horn segment 14 axial length (cm)
L1516 = 5.453888e-2; |Horn segment 15 axial length (cm)
L1617 = 5.582412e-2; |Horn segment 16 axial length (cm)
L1718 = 1.20269e-2; |Horn segment 17 axial length (cm)
L1819 = 5.869432e-2; |Horn segment 18 axial length (cm)
L1920 = 6.282436e-2; |Horn segment 19 axial length (cm)
L2021 = 1.371346e-2; |Horn segment 20 axial length (cm)
L2122 = 46.972982e-2; |Horn segment 21a axial length (cm)
L2223 = 2.97434e-2; |Horn segment 22 axial length (cm)
L2324 = 7.91972e-2; |Horn segment 23 axial length (cm)
L2425 = 8.488172e-2; |Horn segment 24 axial length (cm)
L2526 = 2.246376e-2; |Horn segment 25 axial length (cm)
L2627 = 30.794452e-2; |Horn segment 26a axial length (cm)
L2728 = 2.872232e-2; |Horn segment 27 axial length (cm)
L2829 = 11.00836e-2; |Horn segment 28 axial length (cm)
L2930 = 10.296144e-2; |Horn segment 29 axial length (cm)
L3031 = 1.199134e-2; |Horn segment 30 axial length (cm)
L3132 = 27.93238e-2; |Horn segment 31 axial length (cm)
L3233 = 26.647902e-2; |Horn segment 32 axial length (cm)
L3334 = 3.189478e-2; |Horn segment 33 axial length (cm)
L3435 = 6.672834e-2; |Horn segment 34 axial length (cm)

Vtc = 7400e-6; |Throat chamber volume (cc)(Estimated)

Atc = 2026.00e-4; |Throat chamber cross-sectional area (sq cm) (Estimated)



|Parameter Conversions:



Sd = 1680.00e-4; |Diaphragm area (sq cm)



Ltc = Vtc / Atc;

}

|========================================================================================================



|Network node numbers for this tapped horn system:



| 0-Voltage-1

| |

| -Chamber-5-Driver---

| | |

|8-Segment-9-Segment-10-Segment-11-Segment-12-Segment-13-Segment-14-Segment-15-Segment-16-Segment-17-Segment-18-Segment-19-Segment-20-Segment-21-Segment-22-Segment-23-Segment-24-Segment-25-Segment-26-Segment-27-Segment-28-Segment-29-Segment-30-Segment-31-Segment-32-Segment-33-Segment-34-Segment-35-Segment-36-Segment-37-Segment-38-Segment-39-Segment-40-Segment-41-Segment-42-Radiator



|========================================================================================================



Def_Driver 'Driver'



Sd=1680.00cm2

Bl=32.57Tm

Cms=5.35E-05m/N

Rms=13.28Ns/m

fs=32.0001Hz |Mmd = 422.82g not recognised by AkAbak, fs calculated and used instead

Le=1.50mH

Re=3.40ohm

ExpoLe=1



System 'System'



Driver Def='Driver''Driver'

Node=1=0=5=39



Duct 'Throat chamber'

Node=5=9

SD={Atc}

Len={Ltc}

Visc=0



Waveguide 'Segment 1'

Node=8=9

STh={S1}

SMo={S2}

Len={L12}



Waveguide 'Segment 2'

Node=9=10

STh={S2}

SMo={S3}

Len={L23}



Waveguide 'Segment 3'

Node=10=11

STh={S3}

SMo={S4}

Len={L34}



Waveguide 'Segment 4'

Node=11=12

STh={S4}

SMo={S5}

Len={L45}



Waveguide 'Segment 5'

Node=12=13

STh={S5}

SMo={S6}

Len={L56}



Waveguide 'Segment 6'

Node=13=14

STh={S6}

SMo={S7}

Len={L67}



Waveguide 'Segment 7'

Node=15=14

STh={S8}

SMo={S7}

Len={L78}



Waveguide 'Segment 8'

Node=15=16

STh={S8}

SMo={S9}

Len={L89}



Waveguide 'Segment 9'

Node=16=17

STh={S9}

SMo={S10}

Len={L910}



Waveguide 'Segment 10'

Node=18=17

STh={S11}

SMo={S10}

Len={L1011}



Waveguide 'Segment 11'

Node=18=19

STh={S11}

SMo={S12}

Len={L1112}



Waveguide 'Segment 12'

Node=19=20

STh={S12}

SMo={S13}

Len={L1213}



Waveguide 'Segment 13'

Node=21=20

STh={S14}

SMo={S13}

Len={L1314}



Waveguide 'Segment 14'

Node=21=22

STh={S14}

SMo={S15}

Len={L1415}



Waveguide 'Segment 15'

Node=22=23

STh={S15}

SMo={S16}

Len={L1516}



Waveguide 'Segment 16'

Node=24=23

STh={S17}

SMo={S16}

Len={L1617}



Waveguide 'Segment 17'

Node=24=25

STh={S17}

SMo={S18}

Len={L1718}



Waveguide 'Segment 18'

Node=25=26

STh={S18}

SMo={S19}

Len={L1819}



Waveguide 'Segment 19'

Node=27=26

STh={S20}

SMo={S19}

Len={L1920}



Waveguide 'Segment 20'

Node=28=27

STh={S21}

SMo={S20}

Len={L2021}



Waveguide 'Segment 21'

Node=28=29

STh={S21}

SMo={S22}

Len={L2122}



Waveguide 'Segment 21b'

Node=28=29

STh={S21}

SMo={S22}

Len={L2122}



Waveguide 'Segment 22'

Node=29=30

STh={S22}

SMo={S23}

Len={L2223}



Waveguide 'Segment 23'

Node=30=31

STh={S23}

SMo={S24}

Len={L2324}



Waveguide 'Segment 24'

Node=32=31

STh={S25}

SMo={S24}

Len={L2425}



Waveguide 'Segment 25'

Node=33=32

STh={S26}

SMo={S25}

Len={L2526}



Waveguide 'Segment 26'

Node=33=34

STh={S26}

SMo={S27}

Len={L2627}



Waveguide 'Segment 26b'

Node=33=34

STh={S26}

SMo={S27}

Len={L2627}


Waveguide 'Segment 27'

Node=34=35

STh={S27}

SMo={S28}

Len={L2728}


Waveguide 'Segment 28'

Node=36=35

STh={S28}

SMo={S29}

Len={L2829}


Waveguide 'Segment 29'

Node=36=37

STh={S30}

SMo={S29}

Len={L2930}


Waveguide 'Segment 30'

Node=37=38

STh={S30}

SMo={S31}

Len={L3031}


Waveguide 'Segment 31'

Node=39=38

STh={S32}

SMo={S31}

Len={L3132}


Waveguide 'Segment 32'

Node=39=40

STh={S32}

SMo={S33}

Len={L3233}


Waveguide 'Segment 33'

Node=40=41

STh={S33}

SMo={S34}

Len={L3334}


Waveguide 'Segment 34'

Node=41=42

STh={S34}

SMo={S35}

Len={L3435}

Radiator 'Horn mouth'

Node=42

SD={S35}

I'm seeking some advice as to what rating a stepdown XFMR (VA, voltage) would require to be a candidate for stepping 12VAC up to 25-26VAC/CT (i.e. 50VAC series) when reverse-fed (i.e. primary/sec swapped). This is to create a bipolar supply (317/337 regulation) of ± 27-30V, with 60mA draw on each rail, to power a graphic EQ with discrete op amps. I'd like to apply Elvee's D-Noizator mod as well.

I have tried this with a 6VA 48V (24-CT-24) split bobbin XFMR (Triad Magnetics FS48-125-C2), and the results were abysmal. Flipping the XFMR and feeding the series secondary as a primary yielded 2 X 23.3VAC, or 32V rectified, (no load). These rails collapse to <14V with even a 1K load across them. Obviously this XFMR is woefully underrated for what I'm trying to do. The 12VAC supply was a 10A rated supply; the 12VAC supply did not sag, nor did it have any DC on it.

I now understand that XFMRs are not inherently bidirectional, and have extra windings to account for regulation. So it seems one must up the VA rating to antitipate lossy operation when reverse-feeding, and plan for the loss of voltage due to regulation compensation, the question is by how much? Are split bobbins notoriously bad for this? I've read toroids might offer better performance in this regard (?)

A copmpany engineer suggested a 7VA toroid would hold up to my demands, but I'm not so sure.

This is for a guitar effects pedal with discrete op amps that run at 25-30V. Connecting to mains isn't an option for me (and effects pedals typically have wall adapters anyway), and the emissions testing required for a SMPS is also prohibitive at this stage (I may make these units for commercial sale at some point). The plan is to utilise wall wart 12VAC adapters. There are other effects pedals that flip prim/sec sides to step up voltages in this manner (e.g. for tube plate voltages), which is where I hatched the idea.

I'm going to have to buy a bunch of different XFMRs to try out, but any advice on ballpark XFMR ratings (and what I need to consider generally) would help me greatly in saving on getting redundant parts.

TL;DR: Seeking advice on mimum XFMR specs for reverse feeding as a stepup (12VAC into secondary, now acting as primary) to obtain bipolar supply of ± 27-30V, 60mA draw per rail.

Thank you very much.

Hey all, new member. Super interested in HAM and Commerical radio. and interfacing with such! hope to get some answers and be able to provide some too!

Hello Masters, i need advise hopefully to resolve hum issue.
The monoblocks are Cary 805B - they're SET DHT with 6sl7 > 300B > 211.
When they turned on and connected to speakers and disconnected from a PRE - virtually zero hum comes from speakers (klipsch La Scala with 104 db sensitivity).
When RCA cables are connected from the PRE - 50hz hum appears. Not too bad - but it's there.
Hum level lower when only one monoblock is connected to the PRE. When both are connected the hum is louder.
Basic digital voltmeter (not sure if it's True RMS) shows 0.3-0.4 mv AC at speaker outputs.

Nothing connected to the PREamp.
Power cables of the PRE and the monoblocks go to the same AC strip (no filtering).
All equipment in the room is unplugged from AC.
AC receptacles + cables are USA style - so only one way is possible.

Different sets of power cables were tested.
2 sets of RCA cables were tested (all 3m/10ft length).
2 preamps were tested.

With 2 other stereo power amps i don't have this issue - both are tube push-pull, but one chassis stereo, not separate monoblocks...

What do you think?
Is there a hope?
Or having DHT with separate chassis i'm doomed for hum?

Thanks in advance !!!!

Thank you 🙏
I’m here to learn and have fun.
I have a set of Castle Dover that are going to sing for me soon.

ONLY 12 PAIRS LEFT. HURRY UP.

€80 FOR THE REST, REGISTERED SHIPPING INCLUDED.

I have a few hundred pairs for sale. As you can see they are quite old, the 2SA is green.

Also unopened plastic bags of 50 each. Not shown here.

Price $6/pair.

R

Hello Friends, I'm looking for help pn Onkyo A-9755 service manual please can somebody help me please. Alex

I have good soldering skills, have built 10 or so tuner, preamp, amp kits in my life, both SS and tube.
But never had an identical pair of kits waiting to be built. So my question:

Should I build both kits simultaneously, or finish one before I start the second?
I am leaning towards doing both at the same time but I can see one big risk to that; if I later find I did something wrong, I likely will have done it wrong twice, and will need to fix it twice!

What say you?

This thread intended to be an information resource for all. Please post measured data and photos for complimentary pairs in one post. The data will be condensed so we have a single post for each type to make things easy to look up. It will be a sticky.

I would like to thank MikeB for encouraging the creation of this resource, and all the members who have collected and posted information previously. Also the members who post new data. We will condense new information into a pre-existing post for the type number. All O.T. posts will be removed to keep this thread clean and useful.

My hope is that this thread will assist members in their semiconductor purchases. Another thread on this can be found here.

-Chris

Hello,

I've long been interested in listening to some Frugalhorn type speakers, but have never come across a pair. I am wondering if anyone within a couple of hours driving distance of southern Maine might have built something similar and wouldn't mind hosting a listening session.

Thanks,
Alan

The ZEN Amplifier concept is simple. But it works great.
Here is such an amplifier but with less current and uses IRF610 as MOSFET.
It makes a simple and sweet headphone amp.

Building shouldn't be difficult.
The heatsinking it takes is not so much.
There is some THD, but it is mainly 2nd harmonic.
So, it would be good listening.

The amp is designed for 32 Ohms headphones.
For other impedances it may need tweaking to make it alright.

Here is something I didn't expect: Mouser electronics https://www.mouser.com/ sells Visaton drivers and even entire speakers!

They sell individual drivers too.


I looked up the price for one randomly-selected driver - TIW250XS8, a very nice 8" woofer.
Parts express: $296.98
Mouser: $238.74

I'm just so surprised. Does anyone know how Mouser's price for a whole speaker compare to retail stores?

How to design this?
Is it possible?
Anyone has done this?
There are many opamps that have Rail to Rail output.
So, I am sure this can be done - but I just can not figure out how...

Virtually new Mackie hard disc recorder, 24 tracks simultaneous recording, mounted in Gator hard case. A number of DB25 cables for input and output are also included.

Because if bulk and lack of original box, only available for free pickup in Washington DC area (Bethesda MD).

PM if you need photos but really, since it is free, do really need the photos?

I have some 2sk2013/2sj313 for sale.
Matched Pair
Matched Quartet
Matched Octet
Shipping with tracking number 15usd
(10usd without tracking)

I have started a new Phono Stage project. After watching Stephe's series and reading a lot of the discussions I decided to get one of the built up Chinese clones and then upgrade the critical components. I settled on the two chassis version with a volume control. I think that I have a plan!

In addition to Stephe's series I got a lot of ideas from the discussion here: https://www.lencoheaven.net/forum/index.php?topic=26658.0

I got a unit without tubes for $158 from AliExpress. Shipping via DHL was like 75 bucks. I was amazed that they got it to Pennsylvania from Hong Kong in four days!



It looks very nicely put together inside and out. These things are not available on Amazon and I don't think that they are really intended for the American market, but rather aimed at audiophiles in Hong Kong.

I auditioned it briefly as it came and it's not bad. There is plenty of gain and no noise or hum to speak of. The tonal balance seems pretty even and extended. The soundstage was not very wide or deep at all. Focus was okay on that miniature stage.

The first upgrade on my list is to add the choke to the power supply and I got that done this afternoon.


The replacement coupling caps should be here tomorrow. I ended up getting two Mundorfs and one Clarity Cap. Mundorf makes a 0.15 mf but I couldn't find them.

I have decided to go closer to Stephe's plan and not remove the subsonic filter between V2 and V3 as Thorsten's mods do. I am using Robert's RIAA values, however. I have ordered the precision mica caps and resistors to replace the RIAA filters. The parts here are just okay.


I have decided to also bypass the electrolytics on the signal board and ordered the film caps needed. While I'm at it I'm going to put caps across the tube heaters. These will go on the bottom of the board.

The power supply is marked 115v and the voltages are just a bit high with my 123ish wall voltage. Not out of spec but higher than ideal: B+ is around 297 and my heaters are at like 6.7 volts. The treatise that I linked above describes how to change the diodes to adjust B+ and which resistors to change for the 6.3 circuit, but I think that I'm just going to build a bucking transformer. It seems like a 6.3v heater circuit transformer would be just right.

I'll let you all know how it goes and how it sounds as I go.

Pete

I am replacing the RCA hardwire cable for a turntable restoration. The cable is connected to the turntable via the pictured harness. The middle black wire is ground wire that connects to the receiver/pre-amp, the outer wires are right and left signal and ground. The second image is the Mogami 2549 cable I am using. So I do this correctly, do I trim the shield on both ends of the Mogami and connect one wire for signal, the other for ground, for both R/L connections on the RCA connector and the turntable harness? I will connect a 5th wire for the component ground (middle black wire on harness)

appreciate the help

Hoo-boy... goes back now 4 decades of the hobby on and off... But, I came by it honestly. My dad wrote for Stereo Review for many years and I helped out with testing gear back then, which morphed into reviving old Dynaco gear, which morphed into obsessively reading and building things in The Audio Amateur, which even led to writing a few things for Speaker Builder, which led to amps, DACs, speakers, etc. Now, getting back into things with a DSP DAC project.

Hello everyone.

To whomever it may concern, I'll be asking question about DIY speaker building and hopefully someone will answer my question.

- Zwam

I restore vintage audio components, primarily turntables, but interested in receivers and tube amps. I look forward to gaining valuable insight from everyone. Cheers!

Hello everyone!
I'm an audio enthusiast! DIY Audio,Music.

This looks totally familiar yet I can't seem to find a match in google let alone digikey. Only visible markings are "MX" and "14D".

P15 on the PCB is intact. P8 is broken but they're the same. Thanks in advance!

Hello I am new to the site and am hoping someone with knowledge of the Luxman Lv105 can chime in with some information .. I purchased this unit as a fixer upper ,I have a LV103 and love it . Had a chance and a Lv105 not the U version , for very cheap because it's been messed with by a real hack. Anyway my first problem is getting a usable schematic for this amp ,I downloaded one but the numbers on my board are not the same as the schematic making it impossible to get your bearings . first thing I need to identify is a resistor on the protection board , it's been removed for some reason so I have nothing to go by .. on the board it's printed R-7376 . More questions to come but thought I would start simple . cheers and thanks in advance for any help .. Roger