What are the sonic benefits of using a CCS as an anode load?
I know that a CCS presents a "better" anode load for a tube and that the tube in question becomes more linear,
which should also mean less distortion.
Also the voltage swing should be greater as I understand it.
So, I guess my question is this: -Has anyone built an amp and compared the sonic qualities of a resistor as an anode load
and a CCS as a load?

I’m a self-taught engineer and a newcomer to DIY audio. I recently built my first amplifier. Instead of using the blameless or BC-1 as a reference, my goal was to create something simple that wasn’t based on an existing design. No long tail pairs, no current sources, just enough silicon for playing music. To make it a bit interesting, I adhered to one self imposed constraint; avoid coupling capacitors or inductors in the signal path. The result is a push-pull class A amplifier that I call Project Delta.

Output power? About 15 watts into 8 ohms.
Distortion? I estimate 1% at peak power, primarily second order.
Frequency response? Yes.

I didn’t try to do it perfectly, just to do it myself. By that measure, I succeeded in all I set out to do. As luck would have it, it also sounds good to me.

I have little to no ability, know-how, or desire to take meaningful measurements. If that’s what you’re here for, accept my deepest apologies. Attached is a simplified circuit diagram and pictures of my monoblocks if it may satisfy your curiosity.

The old location's use ends Dec 2023. Blessing in disguise as nothing sounded good in that basement room.
Lets upgrade!! Ideas?

hi guys, i have a audio research classic 30 maybe by chance anyone can help me figure what code for this transistor part of my amplifier.

Q2 orange red orange - based on the diagram

Q2 orange red yellow - based on actual

anyone can help what transistor is this or code of this transistor?

Hi, which Is the Máximum AC Voltage for 5U4G or 5Z3 or 5931 rectifier tubes with a decent good life?

attached is below is an online PDF of the service manual, but some cursory online searches ended up w "make a new trafo that's half the size" lol, which is way above my skill level...

cd94 service manual

p sure the one im looking at it is NOT a mkii, if that helps at all...

Hello, I'm working on a Hohner Symphonic 310 Organ, which I want to restore to it's original specifications, as it was heavily modified by a very sloppy person before.

The power supply had been modified for it to barely work, I suspect one of the original selenium rectifiers blew so they had to replace it with a silicon one, but in the process they bypassed the voltage selector and directly used the 120v mains for a section of the power supply.

Here's the state that I received the amplifier/power supply, as you can see, it's horrible.



now, I've managed to obtain the original schematic from Hohner, and my next step is to restore the power supply, using new components to replace the smelly rectifiers and the old capacitors.
but now I can't figure out how to wire the transformer for the rectifiers.


In the schematic, the 110v and 240v secondaries are shown as independent secondaries, but my transformer has the 110v and 240v secondaries connected in series.

Is there any way to wire my transformer to provide the needed 240v and 350v to two separate full wave rectifiers as shown in the schematic?
I'm not 100% sure but I think the transformer was modified, should I just try to get it rewound or is there way to make it work?
here's a picture of the power supply and amplifier unit after a needed clean, on the bottom left is the transformer in question.




Thanks for the help.

Related notes, advise if you want.

Most importantly, this is a passion project and I'm very much a beginner. I'm aware of the dangers of high voltage and I'm okay with damaging or breaking things in the process, maybe I'm in over my head but I like the challenge.

I'm planning to replace the rectifiers with 1N400X diodes, using dropping resistors to lower voltages where they should be. I'm looking into a solution similar to these, to be able to screw them in place of the old ones so it looks nice.

I think I'll use a 10nf safety capacitor for the "death capacitor" in the primary. Today I was able to find one in a local shop but it's rated for 3kv, is that okay or should I try finding one rated for 400v, or should I just get rid of it and do as this recommends.

I'm in the process of acquiring replacements for the capacitors, I'm just getting new aluminum electrolytics, and probably this for one of the more difficult ones to find. I wonder if I should empty the cans and put the new caps in for a better look, I think if I don't it's going to look too messy for my liking.

About the regulator valves: I'm not sure if they work, as they were also bypassed in the circuit, (which in combination with all the jank made the organ behave in a funny way when anything else was using enough power in the house... like turn on an appliance and the pitch goes down and the oscillators go out of whack and make funny gargling noises.) Is it worth to try to find replacements for the regulator valves, or should I replace them with something else?

I've already posted here asking for help about the reverb unit which is also missing completely, and I'm looking into the options for finding a replacement.
I have attached the full schematic in this post, as it seems to be the only copy of it online, or at least I couldn't find it so I had to ask Hohner.

I'll probably keep posting as things come up in the journey of fixing this thing.

I am looking for a list that Bill published featuring all the steps he follows to create a crossover in XSim. Anyone have this or know how to find it?

I'm thinking of buying a NOS Japanese direct drive TT but I'm confused with their spec.s. Many dd Technics had wow and flutter of .025% and rumble numbers like 78dB. Pioneer TTs had similar wow and flutter of .025% but rumble of 70dB. Did Pioneer used a different rumble standard. It seems like Pioneer spec.s put it at a disadvantage.
thanks

Hey all, got another fun project. I bought a B&K AV30.2 Amp "Brick" and was surprised to see an ICEPower 50ASX2 module in it...cool, as I have not yet heard one of these ASX units.

Anyway, the ICEPower 50ASX2 module is run in SE mode - 2 channel. It plays for a few seconds then cuts out. I have separated the preamp/buffer and ran a signal straight to the amp to determine if the fault lie with the preamp section or amp - it is with the amp.

I checked pin 1/2/3 - Enable/overcurrent/thermal pinouts. When amp is properly playing, they all show 4.89v (good). When it stops playing, the Enable pinout internally goes dead (.2v), while the other two pins are still at 5v (good).

Now according to manual, the Thermal and Overcurrent pins are output only - while the enable is both input and output - meaning an external source can pull down the 5V to 0V to shut down the amp on enable pin, AND/OR the amp can be shut down internally (sending the pin from 5v to 0v) by Thermal or Undervoltage issues. Now since the Thermal pinout shows fine at 5v (why the redundancy here?), it leaves the Undervoltage as being the culprit for the amp is going into protection...I checked and it is jumpered on 115v...

I have seen a few of these B&K AV30.2 amps that have the ICEPower 50ASX2 modules doing the same thing - play and then go silent...don't know if they modified the 50ASX2 or just an issue with the ICEpower unit itself...

Anyway, anyone have any ideas?

Hello, I have a Electrocompaniet Ampliwire 250 that is having relay issue with one of the output channel. I know the relay is bad but the issue is how to get it off the PCB without destroying the board. It looks like some sort of glue or epoxy was used to adhere the relay to the pcb.

Has anyone here removed those relays without damage to the pcb?

Hello to everyone here .. i was on vacation this time , and i decided to make something simple .. i found an old speaker monitor in my storage and thought of making it into a guitar amp .. i made a simple amp with tda2030 and a higain preamp .. everything works perfectly and i designed it too front panel on the 3d printer, but the problem is the following. the whole box is plastic and besides that if I feed it with a transformer that doesn't have a ground, a hum noise is heard,, does this solve the problem somehow or do I have to put a transformer with ground,, to be more clear, I mean the transformer I have put it, it does not have a ground plug in the wall AC, it only has the 2 terminals., thank you

Hello,

I just bought those speakers in title.

Few questions:

I have read from inernet that its good to bypass that protection circuit.
What is the point with this story?

I need some spare parts for those speakers. Just a little things.
Controlling buttons to that protection circuit. Those what are on upper part of front baffle. Buttons have lightbulb logo and lightbulb logo overwrited with slash. And third button also with dunno what kind of logo. What does those buttons do? I also need 4pcs of B&W logos.
Where i can get those?

I don`t know that is this area right for this kind o question, but i hope i get some answers.

THANKS !


Here is example picture of B&W 801 Series 80:

Greetings all,

could anybody identify the driver in the attached images?

Kindest regards,

M

For a Manzanita project. As always, these seem to be hard to find in the US. If anyone has a pair and would be interested in parting with them let me know.

Peerless SLS-830669

For sale troels Gravesen nomex mkii crossover.
Sadly not assembled and I have not enough time to do so.
I will provide the parts (the level 2 version, Jantzen standard caps on woofer and mid, Jantzen superior on tweeter, cored coil on woofer (1.4mm no discs), air core coils on mid(1.4mm) and tweeter section and superes 10w resistors and of course the schematic.


Price is 250 euros including shipping for EU
I accept PayPal

I'm planning a pair of subwoofer 'stands' with 10" or 12" drivers to go under my stand mounts that have 8" woofers. Range will be 20hz - 80hz.

In terms of SPL the super high Xmax drivers such as Dayton Ultimax UM10-22 seem impressive with 19mm xmax.

My question is, do these type of drivers also provide low distortion or is it SPL at all costs?

There is also the Dayton RSS266 variants with a bit less Xmax 12mm and a similar price.

Or I could step back again in SPL with a pair or 3 standard 8" woofers having about 6mm xmax, not subs.

I guess I'm asking if higher xmax sacrifices linearity at more 'normal' operating levels.

My goal this year was to repair water/mold damage caused by inept window installer contractors. They left gaps in the flashing that let water go behind the siding and inside the wall. They also demolished my original drip rails and this of course allowed water to seep behind the exterior flashing and inside the wall.

There's a lot of steps to this job so I was ready to hire multiple contractors and/or coordinate some of it myself. My first attempts to hire licensed contractors yielded people that didn't actually want to repair anything; just slap some siding over it and charge me thousand$. They were pushy and arrogant and I was very dissatisfied with their open ended ($$$$$$$$$$$$$$$$$$$) proposals that required large (tens of thousands of dollars) retainers. OK I can do better.

I made a plan and lined up some unskilled labor ( my buddies and some guys I hired at the Home Depot loading dock; there's guys there every day looking for work and they'll bust their heinies for a few hundred dollars). Stripped two layers of siding and all the sheathing. The sheathing was still wet and there was extensive mold damage. Treated everything with fungicide, did a few small repairs while the walls were open, installed R13 insulation (there was NO insulation), installed new sheathing (the good stuff CDX "Sheathing rated" plywood), flashing, housewrap, flash tape, NEW drip rails, NO LEAKS finally.

Now I'm interviewing siding contractors. Everything is 100% kosher and ALL I need is siding. Well, they want to use THEIR sheathing (can't explain why) and THEIR housewrap (Tyvek isn't good enough?) . They want to rip ALL the flashing off (now that it finally doesn't leak) and basically just cram it right back up my ***.

You can't win at this game. Bottom line is that I don't trust their craftsmanship after being burned before. Maybe I'm going to end up hiring more guys at Home Depot. Yelp has nothing but glowing reviews, even for contractors I know for a fact are shady. They don't want to fix anything; they just want to make money.

the boat anchor manual archive www.bama.edebris.com seems to have an issue. to download manuals you must have javascript enabled. I have this for both Chrome and MS Edge. Still can't download manuals.

This seems to be a recent phenomena.

Any clues.

.

I've been using a free air impedance sweep with the driver cone held out (+ve direction) and held in (-ve direction) as a proxy to measure a driver's Le(x): inductance variation as a function of cone/voice coil movement.

A primer is here:

"Le(x) is a driver test result that shows how inductance changes based on the position of the voice coil in the magnetic gap. Generally, better performing drivers with complex motors do not have substantial changes in inductance throughout their operating excursion, while inexpensive low end drivers with simple motors have much higher inductance with coil inwards and lower inductance with the coil outwards. Le(x) related distortion is a major product of intermodulation distortion and amplitude modulation distortion. This is a form of distortion that is based purely on excursion, and is more of an issue with louder output and higher signal complexity.

There are two ways of displaying Le(x) results. One way is a curve with Le on the Y axis and MM excursion on the X axis, with 0mm in the center showing the at-rest inductance. This is how the Klippel testing system displays the results. The other way is an impedance vs frequency plot with impedance on the Y axis and frequency on the X axis. These are created with the driver cone clamped or held in place, and several plots are needed at various excursion positions. This form is much easier to do with cheaper testing software, and it is what we are showing below.

Each of these Le(x) plots is comprised of 3 impedance curves. One is at rest, one is at the full inward Xmax position and the other is at the full outward Xmax position. Of course, the mm of cone offset depends on the driver's available Xmax. In executing this test, to avoid inaccurate results, the operator has to be very careful of not exceeding the inward or outward excursion.

In these 3 curves, the one with the driver at rest is not clamped or held, and therefore has the full free-air resonance peak shown. The 2 curves with the driver held in position typically mangle the resonance however. As such, the curves are only accurate above roughly 300 or 400 Hz and grayed out below that. For drivers 7" and under, the typical change in Le impedance curves happen above 300 Hz anyway, so this is normally not a limitation.

Note that the vertical scale of these plots is relatively compressed, so minor curve offsets are relatively major in audibility at high output levels. Also keep in mind the expected bandwidth of the driver in question. Smaller drivers are expected to operate higher in frequency and top end Le(x) performance becomes more important in these cases. Along with harmonic distortion sweeps and response curve usability, Le(x) plots can also help you decide on an optimum crossover frequency.

Ideal performance in these test results would be all three curves falling on top of each other at least an octave past the driver's usable frequency range. (or up to 8-10kHz in the case of a wide/full range driver) Poor results would be three greatly offset curves way down into the lower midrange."

Reference:
http://www.zaphaudio.com/Le(x)/

Klippel has also written about it:


Reference: pending…


So here are my test results for various drivers.

10”
Peerless 10" woofer- model 830668 (8 ohm driver)


Green- cone at rest (as evident by peak at Fs)
Pink- cone held in
Blue- cone held out


Bowers and Wilkins 10" woofer from 801 D4 loudspeaker (8 ohm driver)



Bottom curve (pink)- rest position
Blue curve - cone held inwards
Orange curve- cone held outwards

12”
Peerless / Tymphany 12" woofer, model 835017 (4ohm driver)



Green- cone neutral
Pink - cone held in
Blue- cone held out

8”
Purifi 8" midwoofer, model PTT8.0X08-NAB (8 ohm driver)


Green - cone neutral
Purple -cone held in...
Green - cone held out


Commentary:

I use the same impedance scale 0-150 ohms, and 5Hz to 20KHz for all.
It is quick and easy to do with today's available tools eg. Woofer Tester 3 or DATS or impedance jig for ARTA/REW.
As time allows, I will editing the original post with other drivers.

As usual these tests are from the drivers on my shelf, no Amazon affiliations or kickbacks from manufacturers allowed and advertisement free.
This is for learning/shared understanding only. If you want to send me a driver for testing- please don’t. One of the great things about this test is that you can do it yourself- with relative ease (no need to build an enclosure) and it takes minutes to do (unlike harmonic distortion testing which takes hours)

Comments on the usefulness, relative importance of IMD and AMD, and limitations of this testing method are welcome.
Suggestions for other drivers welcome.
Also, feel free to add your drivers.

Recently got an Arcam Delta 290 - believe it to be a later model with IRFP240 mosfets mounted vertically on a heatsink and built in phono preamp. Originally it had no power and a blown fuse. Checked the output mosfets found Q1 to be shorted, removed Q1 and Q2, replaced the fuse and the amp powered on ok.

I've ordered 10x new IRFP240 from Farnell and replaced both Q1 and Q2 the amp then came on ok for a few seconds light went green and then a few seconds later I smelled something burning and the light went orange. Checked and Q1 and Q2 are both shorted dead again and also R1 and R1A. Went through the whole circuit checked all resistors and diodes and replaced a few resistors that were damaged. None of the transistors or diodes were showing shorted so I replaced Q1 and Q2 again - this time the amp came on again for a few seconds and then immediately blew the fuse just before the light should turn from orange to green. Again Q1 and Q2 are dead.

I do not really know where to go from here - I do not really want to keep replacing Q1 and Q2 if it isn't going to fix the problem but I can see no faults or shorted components that would explain why these keep burning.

Maybe someone here knows more about this model and can point me in the right direction or maybe Farnell are selling garbage IRFP240 chips? Am I correct in my assumption that all the output mosfets run off the same Power supply so that if there was a PSU issue surely it should be burning all of the output mosfets?

Hello,
i want to use 2xecc99 as power tubes in a little amp, but for the heaters they require 2x800 mA, so 1600 mA, and my 6.3V output is rated for 1500 only.
So i tried, the amp works fine but the tranny is warm, not hot but warm. I can touch it, it does not hurt at all.
But is it that bad to have 6.66 % overload on the heater winding?
Thanks

by Phil Taylor

https://www.effectrode.com/knowledge-base/delia-derbyshire-recording-the-future/

excellent article!

I managed to pickup a wonderful pair of Pentacone Pentowther speakers with Lowther PM6a drivers that needed a recone. After a week away with Lowther they came back sounding fantastic.
Now a year on and the drivers have finally settled from a crazy run in period I'm looking for information on these rare UK speakers.
After a search I found that Pentacone was briefly on this very site over 10 years ago.
Does anyone have any information on these speakers?
Thanks.

Almost finished preamp in search of a good home. I started a Mesmerize a while back and did not finish it. I now have too many irons in the fire and need to refocus on just a few projects. This is Salas' Mesmerize board nearly fully populated. It has not been powered up and tested yet but should be OK. The board and buffer JFET quad alone are worth over $50. Let me know if you have any questions or want make me an offer if you are interested.

Mesmerize Link: https://diyaudiostore.com/products/mezmerize-b1-buffer?_pos=1&_sid=4da3f0447&_ss=r

A very nice two-part interview with Bob, by Tom Fine.

Highly recommended.

I first started working with Bob in 1991 in NYC, when he fastidiously remastered the LP version of Arturo Delmoni's "Songs My Mother Taught Me," which blows the North Star LP into the weeds. Bob later, in Maine, remastered the digital version, which similarly blew the MFSL "Songs My Mother" CD into the weeds.

Bob's SMMTM digital remastering is now available again, this time from IMPEX/Elusive Disc, as a gold CD.

For my last "The Fifth Element" Stereophile column, Bob graciously consented to be interviewed by me. If you don't recall it, it is very much worth revisiting.

With all my best wishes to Bob and Gail.

john

I have for sale a pair of AD1862N-D DAC Chips. They were pulled from Denon CD Player. 100% authentic and in working condition. This is a special selection of AD1862 which were manufactured fro Denon.
Asking 100$ for the pair plus the shipping. Shipping to USA and Canada .

Recently the Superphon Revelation MK II preamp has come my way. Was designed and built by Stan Warren, at one time the other half of PS Audio. Cant' find out much about it though. Performance wise a very good preamp, phono section exceptional.

However the Volume and Balance pots are quite pedestrian and should be upgraded. I have in the parts bin a TKD 25Kohm volume pot. Anybody know if this would be of correct value? Any other help greatly appreciated.

OS, or anybody, can you recommend an amp to build for a 85VDC 1200W SMPS I have sitting here looking for a job?

Hi all,

For those who like to build DAC circuits rather than to apply DAC chips:

While I was working on my valve DAC I got curious about how well a conceptually similar circuit built with CMOS logic gates and active filters could work. Using 74AHC02 and 74AHC08 CMOS logic gates as the DAC (a four-tap return-to-zero FIRDAC) with a very straightforward crystal oscillator and an LT3042 voltage reference, I measured a noise floor of about -97 dB(A) with respect to the maximum signal level. The schematics are attached, the FPGA code is the same as the FPGA code for my valve DAC that can be found on the Linear Audio website.

The FPGA code contains a sigma-delta modulator that has three modes: seventh-order chaotic and two fifth-order modes with embedded pulse width modulator. In the valve DAC the PWM8 mode clearly has the smallest in-band noise, but with the 74AHC02/74AHC08 circuit it hardly makes any difference. The in-band noise floors are nearly the same for all modes:

PWM4: -97.83 dB(A)
chaos: -97.06 dB(A)
PWM4 (repeated measurement): -97.44 dB(A)
PWM8: -98.32 dB(A)

The out of band noise is different, as expected:

chaos: about 1.3 mV RMS
PWM4: about 2 mV RMS
PWM8: about 6.7 mV RMS

The out-of-band values are estimated by looking at the quasi peak-peak noise with an oscilloscope and assuming that the RMS value is about a sixth of the quasi peak-peak value.

The maximum signal level is about 1.96 V RMS. All values are differential voltages, the single-ended voltages are half the differential voltages.

Best regards,
Marcel van de Gevel

Edit, 30 May 2023:
Hans Polak has done measurements and experiments and among many other things, found that the noise floor is substantially lower than I measured, see https://www.diyaudio.com/community/...ith-97-db-a-dynamic-range.313520/post-7363723

Is it possible to source a black front panel for my early version ACA?

I’d be interested to hear from anyone who has laser-cut their own speaker grilles.
Doug

Hello everybody!

I am a newbie and eager to learn, please don't laugh me 😀 for my stupid question.

I have a old denon avp-a1hd preamplifier, recently the sound will be dropped after playing 15 to 20 minutes. I replaced the original small fan with a bigger one, that makes the playing time longer, about 1 to 2 hours depending on room temperature. The problem is only happened when the input source is via digital such as coaxial cable, playing via USB etc. For example, if I connect my cd player via coaxial cable, the problem happens, however if I connect via xlr cable, it works fine.

It has too many pcbs inside the amplifier, I am hesitated to unmounting those board without any clue.
My question is what is the most likely reason for the failure?
Could anyone please help me to work a way to fix the problem? Thank you very much!

Felix

Hello, I recently bought an old diy preamp, i though it was a curcio Daniel design but i am not so sure anymore. My preamp has a riaa and different control for left / right phono, it uses 8 ecc83 and 2 ecc 82. The dc Power supply had a El 34 tube plus another i dont know what it is, small tube like ecc83. The preamp was build in Norway in the 80s or 90s. I have very litle info on it but I post some pictures, perhaps someone knows what design this is. It plays very nice, the Power supply is quite heavy. Any input on design and build quality is very much apreciated, I dont have any info on it.

I have woofer Usher 8955A ( 8 inch) and Scan speak Tweeter D2010/8513
Have anyone can help me to design crossover 2 way?
Thank you very much

Friend has an X1 pre with the cosmetically matching power supply.
He has acquired an Xono phono stage with the smaller black power supply.

Both of these power supplies have two outputs.

First question.
Can both the X1 and Xono be fed from just one of these supplies at the same time ?

Second question.
If this is possible, then is their any risk of sonic degradation in doing so ?

Third question.
There are minor internal differences in these two power supplies.
Is one 'better' than the other ?
Fairly sure I saw something many sleeps ago that some seemed to think the smaller black supply was a little better.
I would like to see if these thoughts are valid or voodoo 🙂

Many thanks 🙂

People, good afternoon! Sorry for the OffTop. Help please. My KSA 300 is under repair. Tell me the number of the chip as in the photo, which analog can be found so that it is like from the factory. And the number of the flat oval transistor on the right (where many).please. If you can, please show the original photos from your amplifiers. Sorry for my English. All the best/Users/maksim/Desktop/16fc5bd3-113c-4b47-8234-2c14c5ea3df8.JPG
/Users/maksim/Desktop/IMG_8459.jpg
/Users/maksim/Desktop/IMG_8458.PNG

Are 2-way speakers better than 3-way speakers?

2-way speakers have the advantage of having fewer transitions, but they have the problem of not being able to play deep notes (30 hz<).

already 3-way speakers can play deep notes (30 hz <) more easily, in addition to containing a speaker designed for medium frequencies.

my question is, which one has a better soundstage.

Hello everybody.
Whati is quiescent current of Mission 777 amplifier ?

Hello,

i am struggling to understand the compareability of sensivity measurements.

Example:

A driver which is called a 2 Ohm driver has a Re = 1.3 Ohm, a minimum impedance of 2.1 Ohm
A driver which is called a 8 Ohm driver has a Re = 4.5 Ohm, a minimum impdedance of 4.5 Ohm


One question is:

the Impedance value ( 2/8 Ohm ) is a mean value as i understand it. But how is it calculated ?

Is a 8 Ohm driver with Re = 4.5 Ohm still a 8 Ohm driver or more like a 7 Ohm driver ?

I am struggling how much voltage i should set to get a 1W/1M sensivity measurement, as for a 8 Ohm driver i should apply 2,83V to equal 1 W. But 8 Ohm drivers are different the Re range goes from 4.2 Ohm to 6.2 Ohm.

Does that make a difference which voltage i have to set ? Or is it correct to apply 1khz and set 2,83V as long as the driver is labeled 8 Ohm ?

Thank you !

Just collecting some information on JST connectors and Icepower amps. Please help by correcting any mistakes. Good info and links are available on Wikipedia and Matt's Tech Pages.

Definitions:
Header is the part on the ICEpower PCB.
Housing is the white plastic part that holds the contacts (wires), and plugs into the header.
Contact is the small metal piece that crimps on the wire.

High current or voltage use VH (speaker, AC power) or NV (DC power) connectors.
The connector contacts are identical and interchangeable in the VH and NV housings. VH housing has 4.96mm spacing and NV housing 5mm spacing. The VH housing does not fit the NV header. The NV housing does not fit the VH header.
Contact SVH-41T-P1.1 for 16-20 AWG wire
Contact SVH-21T-P1.1 for 18-22 AWG wire

Sample jumper wire JUMPER SVH-41T-P1.1 X2 12" Digi-Key Part Number 455-3107-ND Manufacturer Product Number ASVHSVH16K305
Black 16 AWG Jumper Lead Socket to Socket Tin 12.0" (304.8mm) will work with VH and NV housings. Note that the only available color is black.

Signal or low voltage/current use EH or PH connectors. The connector contacts are virtually the same and interchangeable in the EH and PH housings. As with the VH/NV above, the EH housing will not fit the PH header.
Contact SEH-001T-P0.6 for 22-30 AWG wire
Contact SPH-002T-P0.5S for 24-30 AWG wire

Sample jumper wire JUMPER SEH-001T-P0.6 X2 12" Digi-Key Part Number 455-3104-ND Manufacturer Product Number ASEHSEH22K305
Black 22 AWG Jumper Lead Socket to Socket Tin 12.0" (304.8mm) will work with both EH and PH housings.

JST connector planning:
If the connector is being used for PCB to PCB connection, you probably want contacts and housings on both ends. For example, 200ASC to 200AC. I generally prefer mass produced, machine made wires. Crimping tools are expensive, and there is a learning curve to using them. The difficulty is finding premade with contacts and housings at both ends with decent wire.

The official ICEpower wiring harnesses only have connectors and housings at one end. The same is true for Ghent Audio harnesses.

If connecting a 500ASP (which has VH header for DC bus 50V, +-12V) with a 200AC (which has EH header for +-12V and NV for 47V; and yes, the 200AC is designed to "hang" from the 250ASP or 500ASP, even though they provide absolute maximum 50V to the 200AC) you will need to crimp or solder contacts for the VH to EH wires. The housings and contacts are inexpensive, but plan ahead so you order them at the same time.

The premade crimped wire may have the wrong AWG, wire is low quality or the colors are limited. When soldering wire to the contacts, use enough heat and flux to be sure of a solid solder connection.

Removing wire and contact from the housing:
PH/EH: use a stiff, solid 20 gauge wire as a tool. First, push the connection wire all the way into the housing. Insert the wire tool into the housing on the wire end into the groove until the white tab is pushed up. Then pull on the wire and remove it a few mm, then pull out the wire and tool.

VH: push the connection wire in all the way. Press down on the contact lock tab with a flat screwdriver. Pull out the connection wire.

NV: push the connection wire in all the way. Then insert a 1.2mm flat screwdriver (as found in a cheap precision set) in the hole above the contact hole. Gently pry the screwdriver up, which will push the lock tab on the contact down. Then pull out the wire.

I created an LTSPICE add-on to automate THD measurements and plot result in the form of THD vs. Amplitude and THD vs. Frequency graphs.
I was inspired by "jfet_amp_disto_plot" by Helmut Sennewald, "Audio Distortion Analyser" by Tony Casey and "Fundamental Null Distortion Residual" by jcx from http://www.diyaudio.com/forums/software-tools/101810-spice-simulation-37.html#post133313

How it works:
It outputs sinusoidal signal with amplitude or frequency stepping sweep into device under test (DUT). Output signal from DUT is feed into analyzer input. After waiting some time for signal to become steady state, analyzer restores fundamental and subtracts it from input signal. This subtraction allows to increase resolution or reduce measurement time for the same resolution. You can monitor residual components at “Notch output”.
Residual signal is then fed into synchronous filters and detector. Each harmonic is filtered and measured separately. Maximum of 10 harmonics are analyzed. Amount of harmonics could be easily increased by adding corresponding filters and possessing.



How to use LTSPICE Audio THD Analyzer:

Place THD_Analyzer.asy symbol and Analyser_Controls.txt files in the same directory, where you are saving schematic (DUT schematic),
that you would like to analyze.

Put SPICE directives “.inc Analyzer_Controls.txt” and “.tran 0 {AnalysisTime} {SettlingTime} {MaxTimestep}” in DUT schematic .

Edit “Analyzer_Controls.txt“ to enable (uncomment) appropriate sweep (amplitude or frequency ) and save this file.

Setup “.param Ag=xxx” as amplitude for frequency sweep or “.param Fg=xxx” as frequency for amplitude sweep.

Run the simulation.

After simulation is complete, go to View menu and open SPICE Error Log or use Ctrl+L command.

Click with right mouse button on opened Log file.

Execute “Plot .step’ed .meas data” command. Right mouse button click on opened plot and use Add Trace or Ctrl+A and select the data that you want to plot.

You may want to double click on axis to change axis limits or switch to logarithmic scale.

Notch output shows residual components, after fundamental removal.

Please note that fundamental may not be removed completely. This is not necessarily affecting resolution of measurements as soon as additional synchronous filtering is used to measure amplitude of harmonics.

Increasing SettlingTime and StrobeLength, or (and) decreasing MaxTimestep would likely improve fundamental rejection.

Generator output is DC coupled and has 0 Ohm output impedance. Use external AC coupling and appropriate series resistor if required, to ensure proper operation of simulated circuit.

THD_Analyzer.zip contains all necessary files and example. Unzip all files in the same directory, open “Example_BJT_THD_TEST.asc” and run simulation.
You can monitor analysis progress in the left lower corner of LTSPICE window. After simulation and analysis is complete (including completion of .MEASURE), follow the instructions to display
results.

This unit has (conveniently) 10R cathode resistors on each of the four EL34 output bottles, along with individual bias trimpots.
Have replaced all the worn out EL34s.
Q: How many millivolts do I adjust the pots for (i.e. what is the target anode current at 10mv/ma) ?.
M

I worked for Alan Hill from '77 to '90 and was given a pair of Plasmatronics Hill Type I speakers as a wedding present in 1980. I have resurrected my Hill type I plasma tweeters and added new 6" mids and a 12" subwoofer to them. All of the plasma support electronics had to be redesigned by me (original tubes and power supplies are extinct). I would like to show them at AXPONA 2023 as an homage to Alan and his amazing creation. It was suggested to me that I start a Go Fund Me campaign to offset the cost of show rental space (and Helium!). I am wondering if enough people would be interested to hear these wonderful tweeters.

Hello guys, have an amplifier with audio driver board burnt out, if anyone with a similar board or schematic in part or whole could assist me to reconfigure the missing part of the traces.

Up for sale are my beloved B&C DCX464-8 compression drivers and ME 464 horns (1.4”
These have about only 50hrs of use.
I can provide more pics if anyone is interested
Asking $2500 OBO

Regards!

So I've been wanting to make a wall mounted centre speaker for a while now and come up with what seemed like a good selection of speakers via playing with VirtuixCAD2 and SpeakerBoxLite.com.

Taking performance, size and price into consideration, I came up with an MTM design that has the following:

2 x Peerless SDS-P830656 5.25" 8 ohm woofers.
1 x Peerless XT25BG60-04 1" 4 ohm tweeter.

I came up with an enclosure volume of 12.8 litres and then modelled this enclosure design on TinkerCad:



I built the unit and took measurements with a boom arm and Umik-1 following the guide at AudioScienceReview here and came up with some reasonable looking graphs which follow the manufacturers anechoic graphs close enough to look legit to my untrained eye.



Now comes the tricky part. I seem to have a ~3khz dip in the tweeter response and I'm trying to design the crossover on VirtuixCAD2 and would like some help.
I measured each of the 3 drivers with the Dayton Audio DATS v3 to get accurate t/s specs and then input that data into the software. I think I've got it fairly flat (as best I can) but I'm not sure if the phase response is going to cause issues or if the resistance is too low (going down to about 3.1 ohms).
I'd love some feedback to assist with the crossover design as I want this speaker to sound great!



For some context it's going to be powered by a Denon AVR-X3300W in a 5.1.2 speaker layout and will be mounted to the wall just above the fireplace alcove.

I have a pair of SF W20RC38-04 drivers (4 ohm version) that I'd like to make some 2-way floorstanders with. Was thinking of matching with waveguided D2604/833000 or XT25TG30. I've never designed my own crossover before so was looking for an existing one but came up empty. Anyone know of any existing designs using these 4 ohm 8" SF's? I did come across the Decware DM945, is the crossover published anywhere?

Thanks in advance.

In my opinion, class D amplifier is the largest. And is the only advantage.
Is efficiency. High voltage output makes him meaningful. Low voltage. Its performance is no better than that of class AB amplifier. Please refer to for the specific principle
https://www.diyaudio.com/community/...ss-d-is-class-ab-class-a.388305/#post-7074713

And how high the voltage output is. Will make class D exceed the meaning of class ab.
I think the output voltage sine wave + - 140V voltage is OK. And it is easy to implement.
We can use + -70v or + -75v voltage for power supply.
Use L30D architecture. That is, irs2092s + irfb4227 structure.
https://www.diyaudio.com/community/threads/l30d-irs2092-irfb-4227-iraudamp9-mydiy.280531/
Then use BTL.
It is easy to realize the output + - 140V PP sine wave. That is 280vpp voltage output.
And the distortion is controlled at 0.07%. This will be beyond any class single-chip amplifier design.
And it's very Tu
If anyone is interested, I will design L30D BTL 1000W 8R amplifier.
It may be the amplifier with the lowest distortion of 1000W 8R in the world at present.
Most of those small integrated circuits have more than 10% distortion, 50W 8R, 100W 4R.
For example, tpa3255 ma12070

If we are only satisfied with 50W 8R. 100W 4R (a single chip ClassD usually only indicates 4R power) then any class AB amplifier can easily achieve 50W 8R and 100W 4R
The distortion is less than 0.002%, such as mx50se.
That low-power class D amplifier is meaningless. It needs to convert the audio signal into PWM.
Then convert PWM into audio signal. In order to save 5 watts of electricity at 50W 8R power.
At 10 watts. Class D does not even save power than mx50se. Because I measured it.
Class d always maintains the maximum PWM output voltage.
ok We will only discuss class D now. So is anyone interested

This is an amp I recently built. It sounds good but the NFB circuit resistor values are just guess work because calculating the right values is beyond my ability at this point. Can the two cathode resistors in the preamp be the same value as they are or should the lower resistor be smaller? Also, I wanted a bit more gain to drive the 6V6 so I added that bypass capacitor to the top resistor. Is that a correct way of increasing the gain? Also, what if the lower resistor is eliminated and the top resistor made 1.5K with the bypass capacitor in place. Would that just short the NFB to ground?

I have an Audio Research D-70 tube power amp, and in the manual it says that when running the amp a constricted environment, ensure "ambient air temperate" does not exceed 50C. Where should take this measurement? Above the tube cage? Off to one side?

dear all

I am the owner of an old DIY valve power amplifier bought a long time ago, so i decided to investigate on it

First of all I saw it fits a couple of tamura XE 45 8 out transformers
I read tamura sheets seems that the out trafos are not suggested for a 300B PP
What's your opinion?

First Stage 6SN7WGTA (PHILIPS) Driver 6SN7GTB (SILVANIA) power tubes 300b super 4300a golden dragon, rectifier CV 378
power inductor Tamura A 4004 power trafo Tango 10422

your impression is highly appreciated

Hi,

I own a DACT CT-100 phono stage for more than 20 years. However, I rarely play LPs in the recent years, but keeping the practice of warming it up by just switching on once a week. To my surprise, channel 1 was dead (dead silence) when I tried to playback some LPs last week. I'm not sure whether it could have gone bad unnoticed quite some time ago.

Upon checking the board by comparing with the good channel 2, a ZR431 and a zener diode went bad and both were replaced. Although the supply was restored, but still no sound passing through channel 1. Hence, I am worried about one or more op amps could be faulty. So, I need help to identify what the op amp models are, as all of them are disguised with paint coatings. Greatly appreciate any suggestion to what the possible op amp types/models are (painted white, red and green)? Thanks in advance.

Best regards,

Fong

Just a thought exercise, because I already built a couple of 2-ways with both the Seas W12CY001 and the Vifa NE123-04W, and I've recently put them on to enjoy again.

I can't help feeling the Seas sounds more dynamic and alive but today their prices on the Excell range are crazy.

Today if you wanted to build a ultimate 2-way with a 4" mid-bass what would you choose?? Why?

I need something to use as a preamp/volume control with my Dynaco ST70 series II. Budget is extremely tight, as is space. A tube preamp would be nice, and a kit would be fine, but I don't want to hunt down parts and try to fabricate a case or anything like that. I don't need phono or bluetooth or treble and bass controls. I also thought about just using a cheap DAC witha volume control on it instead of relying on the analog out from my CD/DVD player. I don't know if there is any such thing as a tube DAC or if such a thing would be affordable.

Anyone have any experience with any of these?

https://www.ebay.com/itm/115064545624?var=415147724758

https://www.aliexpress.us/item/3256804370199442.html

https://www.aliexpress.us/item/3256804364966465.html

https://www.aliexpress.us/item/3256804651307261.html

Other ideas?

Looking for one pair of Audax DT101 tweeters in NOS or working condition. Please send me a message if you have some. Thanks.

Hi there
I am building some speakers and want to fit 2 tweeters. I want to keep the cabs 8 ohms to match the bass driver and crossover. The tweeters are 8 ohms each, what would be the best way to wire these? Both tweeters in series with a 16 ohm resister in parallel or both tweeters in parallel and a 4 ohm resister in series? I hope this makes sense. Thanks

I am running my 2x 4 ohm TL subwoofer with a two TPA3116, 2 channel amp on a 24volt 10 A power supply. Would a TPA3255 amp (Aiyima 07) with a 48v 10 A PS give any improvement in bass, like more tight, more control ect. ? any thoughts on the subject?

Dear Solid-State wizards,

I'd like to share with you the all-out hexfet CFP design I've been tweaking over the last months. It's been build rather successfully on breadboard and I started the first attempt at a PCB layout. There is however a very large discrepancy between simulated and measured performance, nevertheless it still is rather good.

Perhaps it is unrealistic to expect optimum performance from a breadboard build. I suspect more performance is to be gained from a well designed PCB layout. The Hexfet CFP may be a fundamentally compromised and Sisyphean approach, but I want to follow through and see how far this design can go.

The Wolverine amplifier for example shows lots of performance is to be gained from well routed tracks. In LT spice I've seen that parasitic impedance in the OPS and PSU can make or break the amplifier's performance. Series inductance in the supply lines, ground and in OPS Mosfet drain&source tracks made my breadboard build to require triple the high frequency compensation with respect to simulation. I'm sure there are many more reasons for the performance discrepancy as im not able to close the performance gap completely by adding parasitic's in LT-spice.

If anyone has the time to review my PCB design I would be very grateful. What makes a good layout goes quite beyond me, therefor I would love to hear your feedback and suggestions. I'd like to gain a better understanding of where performance may be lost in PCB design. First let me share the design and measurements.

Much thanks and cheers,

Ruben

Simplified schematic:​

​

Gain and Phase Margins:​

Circuit currently on Breadboard:​

​

Latest Measurements:​

Testing using a dualpolar 51V raw supply with 10mF resevoir caps and single rectifier. Load is 4 ohm:

10K Clipping:​

Rising and falling edges:​

Arta Testing with 4 ohm load:​

The source and measurement device is a Focusrite Scarlet 2i4. I was not seeing major differences before and after the amp so i'm also showing the measurements at the input of the amplifier.

Here is the source FR:

And The amplifier FR:

Amplifier IMD at 9VRMS into 4 ohm:

Source IMD at input:

THD1k 13VRMS:

THD1k at input:

THD5k 13VRMS:

THD5k at input:

Got myself a pair of MAOP 11.2's and thinking the Pensil A11/P11 will be a good home for them. Have been ogling Frugal XL's as well but prefer the form factor of the Pencils. I also believe they will have a bit higher WAF 🙂.

Now I want to make these as good as possible, so I am planning to make the panels "Constrained layers" by using 15mm BB ply and gluing on 4mm ply with a thick flexible glue like Tech7 or possibly construction foam. This should add up to panels of 20mm thickness. This should be pretty stiff and have excellent damping of ringing in the panels.

Still I guess bracing like super pensil12 would be a good idea? That's my current plan anyways. So when adding bracing to the Pensil A11 I saw Scott recommend to adjust the internal volume to compensate for the volume of the braces. In that post I saw the suggestion was to move the sidewall(s) out and then compensate the port opening for this movement.
I am assuming that compensation would be to make the area of the port the same as before moving the sidewalls, correct?
My first thought for compensating the volume would be to move the back wall of the speaker, but that may perhaps have other consequences for the tuning that are less desirable?
Intuitively seems like a good idea to move the back, since it will not change baffle size and allow the port size to remain the same, but I don't know how all the dimensions here affect the tuning.

Even though this PCA amp sounds pretty sweet, I'm just not a "cans" guy and don't use it at all.
So up for sale it goes. It will include 3 EBL 9V batteries and charging station. (I found regular Duracell 9V's work better though)

SOLD including shipping within USA, Payment via PayPal

Hi. I am a newer member here. I have been doing some reading on full range driver speaker plans including Voigt pipes, folded pipes, open baffles, and bass reflex speakers. I was looking over some speaker plans on the Lii Audio website and found a large bookshelf design that looks similar to folded pipe designs that I have seen before. But this one is much shorter, as it is not a floorstander. The top is also angled downward at the sides. Does anyone know about the principles behind this approach in a bookshelf speaker rather than using a common bass port? Thanks for the help.

This is a great video tutorial (in 3 parts) detailing from concept and design goals to driver selection, cabinet design, crossover and room integration for the ultimate studio monitors. The designers already have fantastic active ATC monitors so they are used to high performance and have well designed rooms.
They test various drivers, crossovers, DSP and room correction, all really interesting and in total makes a up gold mine of information and techniques to copy and clone or experiment and vary to taste... Enjoy!


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Follow up from 4 months ago ( Very Dolby Atmos heavy... Personally I favour Auro 3D for processing everything from mono/stereo to 16.4 movie mix's.) The new Trinnov Nova looks great!
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Hello. I am preparing to sell my dad's Klipschorn's, and want to make sure the crossovers have been wired correctly. I went to check it today, but honestly I don't really recognize some of the things in the schematic. Hoping someone can confirm for me that everything looks good? Pictures attached. They have been reworked by someone else using parts from Bob Crites website

little use and coming into original package and with 3 probes (I don’t remember if one is working). It makes also FFT and can priht screen on usb stick. All in all easy to use and very convenient

https://www.digikey.it/en/products/detail/teledyne-lecroy/WAVEACE-1001/3131289

Selling at 300€ + shipping from Italy

It only saw little use, coming with original package.


https://www.siglent.eu/product/1139798/siglent-sdg805-5mhz-function-arbitrary-waveform-generator

Selling for 100€ + shipping from Italy (basically 50% of list price)

Here’s a YouTube video of Accordion player Alexander Sevastian (apparently, R.I.P) masterfully performing Bach’s, perhaps, most famous work. Alexander’s Accordion sounds much akin to a pipe organ, minus the pedal notes. I must confess, that when I first watched this performance I sat transfixed. Never before realizing that an Accordion could sound good playing classical music. I had ignorantly thought them suitable only for polka. I don’t know what a virtuoso Accordion player sounds like, but I imagine they sound like Alexander does here. Although the video is from 10 years ago, I just now stumbled across it.

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Selling partially completed Leach Low TIM amplifier boards and a box of transistors, resistors, diodes, transistor mounting clips etc. also a couple of leach amplifier boards I bought on Ebay(seems like they were printed too small) Don't think I will get around to finishing this . see pics, make offer .

Hi

This amp was on standby and not powering up. Upon checking Q201(relay drive) was open. After replacing the transistor, the amp turned on as normal. Some of the input source (tuner,tape1) were not functioning. Upon inspecting the front board, I realise that the solder joints were bad, so I took out the front board and resoldered the whole board. After reassembling, the amp does not turn on. It is on standby again. There is 5V present on pin34(Vdd) of the cmos microproccesor, but no voltage on pin80(standy relay). No voltage on pin80 means no base voltage for Q201, the relay drive. I am not familiar with CPUs, and wonder what could have gone wrong. I have checked Q201 and all other components on the power supply board, they are OK. Could the CPU itself be the problem. Pls assist.
Thanks

Hello, everyone.

I'm developing an analog to digital audio conversion project at my school, and while using the PCM1802, I had some questions regarding the clock signals. To use the PCM1802 in slave mode, should I provide the SCKI clock signal to it, or is that only necessary when using it in master mode? Because in the I2S settings in the software, only the BCK, LRCK (WS), and FSYNC clock signals are defined. It's worth noting that the PCM1802 has 4 pins designated for clock signals (SCKI, BCK, LRCK, and FSYNC).
Or should I generate an external clock signal to provide to the SCKI terminal on the PCM1802?

Thank you in advance!

Requesting all the experts to advise whether ported or sealed enclosure would be optimal for HT use

1. I have the sub driver (sb audience Bianca 18sw450 (fs 28hz)

https://www.sbaudience.com/index.php/products/subwoofers/bianco-18sw450/

2. I also have minidsp 2x4 HD
3. 6 cu.feet is the enclosure plan I have in mind (for ported)
4. What should be the recommended frequency? My room size is 21x21 and I may plan to add another sub later.

I could not find any previous references for the sub being discussed for HT use, hence this request.

Thank you

Hi,

I am after some 12AX7WA Philips Jan NOS valves, and ideas of good places to look. I bought my initial stock from Watford valves in the UK, but they no longer have any left.

I am always a little cautious about eBay.

Thanks,

Rich

The MICRO-AMP 😀 :











With D 120mm x H 130mm x W 185mm and 4.5kg, this is probably one of the most compact stereo tube amplifier ever... 😉

T

Hi, I have what was a rather expensive component set (retailed at around $800 cad back in 2011) that I am not using and I am considering using to build a set of hifi home speakers for a 2.1 application. I will power them with a Marantz 1060 in a small room for low to moderate level listening.

https://audison.com/product/av-k6/

ELECTRIC-ACOUSTIC SPECS​

My question is: Will these woofers sound any good in a sealed or ported enclosure? If so what would be the best enclosure for them?

Or will they only sound good in an open baffle application, being designed for car audio.

Thanks for any advice.

There is a lot of good audio amplifier designer-engineers out there but I've always found little talk about Gerald Stanley's designs and contribution to the audio industry through the years he was at Crown International. He holds a large amount of patents on his deisgns. A true innovator in amplifier design and incredible knowledge of semi conductors. Crown would never achieved the success that they did if he wasn't around. A very humble quiet man who always gave credit to other people working at Crown

Four of his patents I most like is the Class AB+B, Grounded Bridge, JTS -ODEP (transistor protection scheme) and the Opposed Current Converter (class I)

Class AB+B in a three deep darlington. The pre-driver and drivers are high speed fT and carry the bias and the tranistors are in class AB mode. The last outputs are lower fT but more durable able to carry the higher current demands. High open loop gain, maximum negative feedback (overall and nested) used to reduce distortion to very low numbers. (Crown DC300). Gerald was using as much negative feedback as possible before any other designer could to get these low distortion numbers and low output impedance (made Crown famous for high damping factors)

Grounded Bridge to get maxumum voltage swing in a smaller package and less parts used. Clever use of the power transfomer not using the ground but creating a floating ground that varies on the sine wave. (inverting when wave goes high or low) moving the ground in proportion. Jim Wordinger also had much input to develop this circuit into the Micro-tech and Macro-Tech designs.

Then came JTS and later ODEP to protect the outputs. A very clever design which made the amplifiers (M600, Micro-tech, Macro-tech, Studio reference) very reliable.

Class I came about in the mid 90's when class D was coming into the commercial pro market. At the time Crown were not happy with the amount of distortion that class D was creating so they Gerald came up with his own design called Opposed Current Convertor Class I. This was released into the Crown K series which has a linear Transformer power supply but utilized the first version of the Class I. In its most simplest form... Where the high and low side switch on and off at the same time into inductors for zero output but vary each sides switching time to create current into a load. A really clever deisgn. This design is still in use in Crowns most recent flagship amplifiers and a Mark Levinson model.

Crown found you never needed very high slew rates (marketing race in some companies) Helped to dispel the TIM SID theory that was hot topic in the late 70's, even coming out with a paper on it by Gerald and Dave McLaughlin (very hard to find on the net) High focus on IMD than THD and a strong believer in using negative feedback to make amplfiers linear as possible

I do think we one Gerald much gratitude on amplifier development.

I offer here a pair of modified Magnepan Magneplanar MG1.6/QR in very good condition.

The heavy 5.4 cm thick frames are made of 18 mm thick, oiled or white lacquered, 13-ply birch plywood. Compared to the original frame made of plain medium density fibreboard, this construction has a much better grip on the resonances of the magnetostatic panels.

The covering consists of a thin, natural-coloured, very sound-permeable linen fabric.

The crossovers are made of high quality parts: Large air coils from Intertechnik with 2 mm wire thickness and MKP foil capacitors from Jantzen and Krummer. Only the original foil capacitor in the parallel branch of the low pass has been retained, as there is nothing to be gained from more expensive components in this position imho.

The crossovers have been removed because they cannot be hidden in the frame due to the size of the components. Originally I wanted to place the crossovers in wooden boxes, but in the end I left them as a permanent temporary solution.

Test listening is possible in Hamburg Hamm-Süd.

Asking € 799,00


NO SHIPPING, PICK-UP ONLY!


Legal notice: I exclude any liability for material defects. Liability for damages due to injuries to health, body or life and grossly negligent and/or intentional violations of my duties as a seller remains unrestricted.

Firstly I'm really pleased I found this forum, seems like a good place to be.

I've always had decent (ish) speakers, mainly for home cinema, but I'm really keen to do a DIY build.

My plan is to build a part storage wall in my living room and actually build the speakers into the storage unit so they are really discrete.

I'm happy to spend around £2k on the speakers (stereo pair) and they will mainly be used for listening to music. Then maybe buy a prebuilt sub, and amp? As I don't want to build everything if I don't have to 🙂

I've watched a few youtube videos and read a few bits on the internet, but I'm not really sure where to get started.

Any recommendations, pointers, advice, obscenities 🙂 would be hugely welcome, as you can probably tell, I don't know what i'm doing.

Thanks in advance

Luc

I have a question for the more theoretically strong persons here.

Would it be a good idea to replace the C1-C4 and L1-L2 in the SOZ powersupply with two 4-pole electrolytic capacitors, why? why not?

Hello everyone!

I hope I've chosen the right topic for the issue I'm encountering regarding modifying a line-level signal. I'm reaching out for advice and guidance on how to address a specific challenge with my audio setup.

I recently got intrigued by the latest Class D amplifier on the market, the new Fosi V3. This amplifier has replaced my FX-Audio FX502Spro, which had taken the place of a Breeze Audio TPA3116 in my system. While the Fosi V3 boasts a subwoofer output, it turns out that it's simply an additional port parallel to the line input. Starting from October, Fosi V3 units will supposedly come with a factory-fitted subwoofer output from the preamp stage. However, it's unlikely that this output will include a low-pass crossover filter for the subwoofer.

To overcome this limitation, here's my plan: In my setup, I have a TV with an optical output connected to a Topping D30 DAC. The DAC's analog output is then connected to the Fosi V3, which drives my primary speakers, a pair of Pioneer SP-FS52 towers.

Additionally, I have a budget-friendly Sony SA-WP780 subwoofer. While I don't have high expectations for its contribution to music playback, I find it useful for enhancing movie viewing experiences.

This subwoofer is active and has only a line-level input. Its speaker impedance is 8 ohms, and its lone control is a volume potentiometer with an exaggeratedly large range that's rather low-fi and practically unusable beyond 20% of its travel. When I play frequency sweeps, I can distinctly hear the subwoofer reproducing the range from 50 to 1700 Hz.

I've ruled out connecting the subwoofer to the dedicated parallel output of the Fosi V3, as I want to avoid altering the impedance and potentially sacrificing high frequencies. Therefore, my plan is to use the RCA analog output of the TV, despite its DAC's known characteristics of being opaque and compressed. However, for my intended purpose, I believe it will suffice.

My goal is to construct a passive filter that completely cuts off frequencies above 80 Hz from the television's line-level output.

Can a passive filter accomplish this goal? I've already attempted to construct a basic RC filter, but the level of attenuation was minimal. Given the subpar quality of the subwoofer, my aim is to completely eliminate frequencies above 80 Hz. The primary intention is to generate a tangible sensation of room vibration for movies and some bass support for music.

I've come across dedicated 12V circuits on platforms like AliExpress, specifically designed for this purpose. These circuits feature stereo input and a subwoofer output, complete with two potentiometers – one for adjusting the frequency cutoff and another for volume control. However, if possible, I'd prefer to build a passive filter since my requirements are fairly straightforward.

I would greatly appreciate any insights, advice, or recommendations that you could offer regarding this project. Thank you in advance for your assistance!