Crossover design software advice needed (refitting a driver)

Dear members

I've got some speakers and one of their tweeters has gone silent.... No longer obtainable.

Some candidates have been located that will a) fit, b) have similar performance (and were suggested as replacements).

I'll need to adjust the crosssover to get it "behaving close to the old tweeter".

I've got the plots for the old tweeter, the ones for the new candidates and the existing crosssover details.

Is there software that will allow me to input the old data, extract the response curve of the old setup and then use that in conjunction with the new driver data to correct the crossover?

Thanks in advance.

Behringer A800 for 2 Way active speaker usage

Hi all!
I have changed the setup slightly and i am wondering if it it possible that such a slight change makes a substantial listening quality difference. I had to use the volume attenuator of the Behringer for the unsymmetrical Cinch inputs because of the very high sensitivity level. Without a precise gain level measurement with measurement equipment it is nearly impossible to get the correct attenuation levels for the right and left channel woofer and tweeter SPL levels with the no good A/B channel Behringer A800 level attenuator stuff. I have tried than to use RCA output to XLR input adapter cable because of this here, from the specs:
Input sensitivity @ level control max XLR: +4 dBu / RCA: -10 dBV
With the adapter cable i can turn all knobs to maximum, easy to use, no level measurement to match the four channels required. Now i have the impression that the sound quality has improved substantially but is it possible? Two ideas of my own:
1) Behringer use bad potentiometer, no budget for ALPS potentiometer for this amplifier - may be it would be far better to throw it out and use fix level with two metal film 0,1 % tolerance resistors.
2) Behringer use no good circuit design for the unsymmetrical input and a better one for the symmetrical input.
Comments are very appreciated, thanks in advance!
- Stefano

Rotel RB850 Rebuild 2019

ROTEL RB850 REBUILD 2019

I have resigned myself that I must do some serious service work on the Rotel RB850. Please find attached relevant support documentation. Questions in the following posts.
Odd part names are left channel, Even part names are right channel

Parts List
http://groundnoiseindustries.com/diyaudio/rotel_rb850/_Rotel_RB850_Parts_List.txt

Redrawn Schematic
http://groundnoiseindustries.com/diyaudio/rotel_rb850/_Rotel_RB850_Redraw.gif

Service Manual
http://groundnoiseindustries.com/diyaudio/rotel_rb850/_Rotel_RB850_Service_Manual.pdf

Capacitor C611-C612 on Board
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1001.JPG

Capacitor C603-C608 on Board
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1004.JPG

Capacitor C601-C604 on Board
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1008.JPG

Power Supply Capacitor on Board (possible leaking)
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1009.JPG

Power Supply Capacitor on Board (possible leaking)
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1010.JPG

Left Side Amplifier
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1012.JPG

Right Side Amplifier
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1013.JPG

Power Supply Capacitor Board Bottom
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1020.JPG

Power Supply Capacitor Board Top
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1021.JPG

Power Supply Capacitor Board Cleaned
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1022.JPG

Capacitor C601-C604
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1023JPG

Capacitor C605-C608
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1024.JPG

Capacitor C609-C612
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1025.JPG

Capacitor C613-C614
http://groundnoiseindustries.com/diyaudio/rotel_rb850/Rotel_1026.JPG

DIY project: streaming music on vinyl

Introduction
I am an audio enthusiast, I like innovation and new technology. But in the audio space I am also very much a 'hybrid' guy. I like the analog HiFi equipment from the '70s, I like DAC's and streaming technology, and I like to make combinations.

So for one of my projects I liked to make such a hybrid setup. Here's what products I took to start with:
This is what I added:
  • Arylic Up2Stream Mini v3, wireless modules to get the Philips MFB speakers connected.
  • Arylic S10 streamer box as a hub between the MFB speakers, the turn table and any music streaming service.

The setup I created looks like this:

Schermafbeelding 2022-09-16 om 17.06.49.png


Speakers: The Up2Stream Mini's have been integrated inside the Philips MFB. They are active and have their own PSU and Amp. So power for the Up2Stream was no issue. The WiFi antenna was led to the outside of the speaker casing (backside) for good WiFi signal.

Turntable: The Lenco L-3808 has its own pre-amp built-in. The audio-out of the Lenco is connected to the audio-in of the S10. But since the S10 is so small, it can easily be put out of sight. This way the turntable does not need any amplifier near by, and can be put at any location with a wall plug nearby. (Women will love that!) The Lenco has a switch on the backside, it should be positioned to 'LINE'. This way the signal from the Lenco will be pre-amplified. Enough to work with the S10.

Configuration: The 4Stream App is used to configure the right setup of the S10 and the 2 MFB speakers. On the left screenshot you can see (from top to down) the Lnceo HUB which is the S10, the left MFB and the right MFB speaker. In the right screenshot, they have al been combined to one system. Note; its important to start with the S10/Lenco HUB, and add the two MFB speakers to the Lenco HUB. This way, the S10 will be the combining hub for all ways of playing music.

IMG_1403.png
IMG_1402.png




Let's play music now!
  • Streaming music: Start music from for instance Spotify, and choose 'Lenco HUB' as your speaker. Music will sound from the MFB speakers.
  • Streaming vinyl: Put a record on the Lenco turn table, and switch the music source in the 4Stream App, from 'WiFi' to 'Line' (see screenshot below). Or use the remote control that comes with the S10 and just push the LINE button on the remote.

IMG_1404.png



Conclusion
If you like streaming and vinyl on turntables, I guarantee this is a fun project and friends visiting you will be astonished.
Have fun and enjoy!

What causes amps to hiss?

I have an older Kenwood amp that I pulled out of storage to test an active speaker I'm building. It works well enough but there is a constant hiss coming from the speaker and it's really audible when there is nothing playing. I was just wondering if there is something in general that would cause that or is it one of those things that could be caused by many different things. If it where cheep and easy I might try and fix it for shots and giggles but if it is a big ordeal to diagnose then it's going to the amp grave yard. So I'm seeking some guidance here. I don't know to much about the internal workings of class AB amps so I was hoping someone here might be able to enlighten me.

True 3way Coaxial

Was pondering the other day has any speaker company ever made a coaxial driver thats a 3 way?(Triaxial)
I dont mean like a car audio where they have a tweeter and super tweeter stuck on a stalk or like a BMS 15CN860 where its a 2way compression driver inside a woofer, more a tweeter inside a midrange inside a woofer? Like 2 cones bass/mid and maybe a dome tweeter all in the one frame so to speak.

Is there such a thing?

USB C parts for PreSonus AR12c

Hi All,

Some days ago I bought a 2nd hand mixer (PreSonus AR12c) which arrived in a miserable state. The biggest issue is that there is no actual USB C interface, meaning that the hole is there but it's empty. So, I've opened the case and I've found out that there is no USB C board... For some reason it was de-soldered or ripped apart (and then removed).

Now, I got full refund + I can keep the mixer. However, I have no use of a mixer without the USB interface, so I'd like to try to fix it by soldering a new USB C board there.

Can anybody help with these two questions?
1) The missing board was connected through pins called P1...P7 (see picture), while the USB C boards that I've found on Amazon have pin names like Ground, D-, D+, CC, etc.. and none with P1...P7. I am not familiar with naming convention of electrical components, so I'm wondering if there is any decoder to understand what P1...P7 means? Or, better, is there any USB C board sold with P1...P7 naming instead of GND, CC, etc..? I've already been in touch with PreSonus and they won't provide any info about this.
2) Is there any solution other than that to fix it? My soldering skills are adequate to work on large parts like resistors, etc.. but I'm not sure I can deal with such a minute contacts. Maybe replacing the whole board would be better? I do not wish to send the mixer out for repair because it will cost too much.

Disclaimer: I'm perfectly aware of the risks of destroying my computer and the mixer if anything goes wrong with soldering. I can take this risk (I have an old guinea-pig PC and I don't care too much about this mixer).

Luca

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Rectifier shorting

This is not my first amp but frst time using this tranformer.
Both heater secondaries are funtioning fine with centertap grounded.

No tubes or caps are connected.
high voltage secondaries (red wires) are disconected from amp

I am using a full wave rectifer on the high voltage secondaries.
the centertap (yellow wires) can be grounded, and the rectifier can be grounded, but not at the same time.
If I do it shorts and the PT hums and shakes like crazy.
when just the rectifier is grounded the voltage drops to 286 from 340 (measuring one side)
I have swapped the diodes with new ones but no change.
measuring the voltage through just the diode measures 340 cathode and 178 anode
Diode is rated for 1kv
two types used 1N5408 and BYv26E

I hope someone has an idead of what migh be going on.

tr320.PNG

rate my practice

I once had a client that owned a club celection systems worked there very fine an excellent set up
So they got another bar and run out of money
they called me and asked me what is possible to be done with the existing equipment
the nature of the bar was in a tourist area had one bar 8meters long and in front of it one dance floor may be 60 sq meters
Exsisting in the shop was one decent amplifier 2*500@8R and one pair of speakers full range 2 way one big BBC woofer and one tweeter ( ???? )
at first thought there was no way that the woofer could meet the tweter expect a huge gap in the upper mid area
target was to move the danceflor if possible and the bar will listen from the left overs
My idea was
use the bins 15" as "subs" placed on thedance floor , convert the all system to active 2way, construct a satelite that will include one 8" midbass and the existing tweeter placed in the ear level of a standing person on the dance floor
Added one more amplifier 2*200@8R+ 2*10 eq and electronic xover
Worked !!!
impact on the dance flor was superb, sound generally was nice and suitable for the use and type of program , satelite speakers was placed properly to move the people there
All worked fine
a few days from opening client was happy since he spent the minimum and sound was fine
Though there was a complain about the kick of the bass
Ammount of bass was not ennough kick of bass wasn't enough
I explaind that the woofer was not proper for such an application and even more the box was not designed for such an application
so the asked me if there is anything to be done with zero budget
I said to them there is one weird idea that i can apply but the results are unpredictable
Like what ? they asked
i said there might be a chance that bass after that is increasd in a level that is not correct and also there is a chance that bass will be floody and wably and dominate over the rest ( plus that you might exceed limits and tourist police might not like that )
Go ahead they said
So a removed the woofer from the box , removed also rubber feet of the box , placed them correctly on the dance flor , drill 4 drills for every bin and screw them on the wooden dance flor pretty tight ....
The same night owner was arrested for violation of laws related to spl
bar worked like that for 2 seasons problem free before sold to another owner .
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Harman Kardon Citation 12, bias value question

I'd replaced a damaged right channel differential pair and Q708 bias resistor. I had the thing dialed in at 40mA per the service instructions. It sounded decent. Two days in the thing made some loud crackling noises, hums, bumps etc like it was throwing major DC.

Going by the schematic values and checking for mVDC instead of mA, I'm getting 2.5mV on the right channel, 0v on the left. I didn't touch the pair on the left channel, or the bias transistor. What is going on with this thing?

Cheap "studio monitors" suggestion?

Hi all, I am a low-budget recording artist/songwriter/composer/producer/mixer etc. I primarily listen and mix on headphones but I'm looking to branch out. Eventually I want to buy some nice Barefoots or Genelecs or something but for now I am going to try and build something decently flat for cheap while I save. I know that I am not going to be able to build proper studio monitors but I am hoping I can find a kit that's reasonably flat at least in the midrange. Is there anything in the DIY world that can beat lower-end studio monitors like the KRK Rokit or Mackie CR4 for a similar kind of price?
I am willing to compromise on total volume output because I listen pretty quiet (personal preference). Thank you very much for your time and expertise.

For Sale Najda 8 channel DSP

For sale a Najda v-1.3 board with the control board that supports all user interface controls (buttons, display, IR sensor, leds, rotary encoder). The board will be shipped from Europe (Portugal)

******** SOLD ********

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Volume control options for tube preamp

Can we run through the common options for volume control on a tube preamp giving pros and cons?

Examples:
  • log volume control
  • fake log using linear taper with a resistor, and best resistor values
  • stepped attenuators of different constructions including shunt types
  • TVC and autoformer
  • other types

What are you using, how did you make that choice, and how do you like it?

FS tube amplifier PCBs of my own design EL84PP EL84SE and PSU boards support included.

Hey Builders!

I have designed some PCBs for tube amplifiers. And have ordered some of each design.

I will be selling these here, for 7.50USD each. Will provide nearly unlimited support over telegram if you purchase some.

Shipping at current PostNL rates. Which are about 12 USD for a 400Gr parcel to North America, and lower for Europe.

I can also supply parts kits for the electronics, and help you source parts.

Cheers, V4lve Lover.
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DML Patents and Licensing

Hi All,
Anybody here have any knowledge regarding the current state of the art in DML/BMR products?

Specifically, if I want to bring a DML-based product to market, then do I assume that the patents and licensing fees are included in the drivers that I purchase from any arbitrary manufacturer, or do I need to pay licensing fees to some schmo for the hard work and I.P. that I've put into my panel designs?

Mods on Bryston 10B Crossover

I just acquired a Bryston 10b after a long search for an electronic XO. I wanted analog, high quality and discrete components. And there aren't a ton of choices.

Once receiving it. I downloaded the schematic and popped the cover. Right away I notice that there are 8 100uf electrolytics directly in line right at the outputs. There are also some small ceramics in the signal path right before the high pass resistor array ( I presume the switch shown in the top right is the 6/12/18dB selector labeled N1/2/3)

It is the standard model, not the Sub. it is the balanced version.

I'd like to upgrade whatever components I can to increase performance. Aside from the components I noted, I'd also be grateful for other suggestions.

Part of the challenge is this unit is only about 2" high, and those electrolytics are on top of a board so there's limited room. One option I considered was to move the PS board to an external box, which would open up room.

Any and all suggestions would be greatly appreciated!

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An Improved Array

I had some time off work, so I've been trying to decipher how the Beolab 90 works. I'm looking forward to hearing it again in a couple weeks. (At CES.)

While studying the patents, I stumbled across an interesting one from Enrique Stiles. In this thread I'll take a stab at describing it.

Mr Stiles' patent is based on the work of Philips. About 35 years ago, Philips patented a novel array named 'the Bessel array.'

The concept of the Bessel array is very simple:

In a conventional line array, the elements sum constructively at low frequency, and destructively at high frequency. Specifically, they'll sum destructively when the frequencies reproduced are shorter than the center-to-center spacing, and they'll sum constructively when the frequencies reproduced are longer than the frequencies reproduced.

The reason that this happens is due to phase and amplitude. At low frequencies, all of the array elements are in phase due to the long wavelengths. At high frequencies, this is no longer true, because the wavelengths are so short. And this gets worse the further you go off axis. (Due to the phase differences.)

So the Bessel array addresses the phase and amplitude issues in two ways. First, two of the five elements are driven with a reduced amplitude. Second, the phase of one element is flipped.

The net result is an improvement in the off-axis response, at the expense of overall amplitude. The overall output of a five element Bessel array is equivalent to the output of a two element line array.


More info can be found here : http://www.diyaudio.com/forums/multi-way/38523-bessel-array.html

Arguably, nearly all attempts to improve array performance are based on attempts to manipulate the phase and amplitude of the array elements. For instance, 'shading' manipulates the amplitude. CBT arrays manipulate phase via physical placement, and also 'shade' the array. IMHO, 'log spaced arrays' are a clever method of shading an array without modifying the voltage.

CLRE0P8.png

Here's a comparison of a conventional five element array, versus a five element Bessel array. Note the improvement in off-axis response, at the expense of overall output. Data is source from Mr Stiles' patent, #US20060018491 A1

P3 Adjustment for the average Hobbyist

After some very recent conversation on the "BA3 as Preamp" thread, several have obtained the 212 interface to use with ARTA or other program is setting of P3.

Some are as lost as I am, others not quite so much. In an effort to enable the average guy to set P3 to one's benefit, (or at least make both channels symmetrical) this thread was created.

Most of those envolved with the discussion either have, or are getting this device:

Focusrite Scarlett 2i2 | Sweetwater

Also, a Tascam unit is listed that would also be appropriate. Some have done this and are going to show how they hooked it up, the rest are flying by the seat of the pants.

This discussion began on the "BA3 as Preamp" thread, post numbers #1298-1313.

Please feel free to join comment inform etc.

Russellc

DIY Turntable plans?

Any plans out there for a DIY turntable? I was thinking it'd be fun to buy some components and build a plinth for them. I'd buy a tonearm, bearing, motor, and probably also a large platter, and then build a handsome plinth to unite them all. But I'm not sure where to begin. I see lots of cool builds online, but many of them seem largely developed entirely by the builder. I lack the science/math skills necessary to design my own system, but if there were some plans out there, I could follow them.
Does such a thing exist?

Tune passive radiators with specs unknown

Hi folks,

I'm new here and opened this thread because couldn't find directions for what I'm looking for.

I want to build a bluetooth boombox-style speaker with two 4" drivers and two 4" PRs.

I went for PRs after modeling for ported speakers with my drivers' specs in winISD, the results with ported was an enormous necessary internal volume for anything under 60-70 Hz.
The thing is I only have access and money for chinese PRs (like these https://aliexpress.com/item/4000203225569.html) but they have no T/S data or any specs for modeling.

Is there some empirical way I can test/measure resonant frequency for tuning it, like a variable sized box or something, and how could I do measurements with it?
I have no pro equipment for measuring.

Any insights would be much appreciated.

Toroid Transformer - Dual 45v Secondaries 600VA

Primary 1 - 0 - 120VAC & 0-120VAC

Secondary 1 - 45VAC -0 & 45VAC -0 (6.6A each)
Secondary 2 - 14.75VAC - 0 - 14.75VAC ( .75A)
Secondary 3 - 17-0 (.2A)

With all hardware. $40 + ship?

I have 2 available...

Pick up in West sub of Chicago or ship

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Hypex Subwoofer Plate Amp

Hypex UCD180LP x2 (Bridged) and SMPS400A180 Power supply Subwoofer plate amp. Specs say 700 wpc @4 ohm.

Works great, but cannot work for what it was intended on project, so up she goes.

These are pro-audio Electrovoice ELX118 plate amps.

$250 + ship from West sub of Chicago?

32hz - 130hz

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Amber 3501 analyzer + parts

I'm selling my Amber 3501 analyzer. I used this analyzer quite a bit 4 - 5yrs ago, but I've been using an Audio Precision Sys 1 since then and this Amber just sits around gathering dust any more. I went through this analyzer back about 5yrs ago, the upper analyzer/oscillator pcb had all of the tantalum caps replaced with new 35V rated tant's and the e-caps were also replaced. I also replaced the tant caps with 35v units on the lower input pcb as well. The power supply board on the rear panel received new caps also.

This analyzer didn't come with the freq meter originally. I purchased a used unit off of Ebay that had the freq meter on it and swapped it onto this 3501. The freq meter is very nice to have on these old analyzers because it makes it so much quicker and easier to see what freq you're testing at. I tested the Freq meter back when I installed it to find out what the upper measurement limit of of it was and it will measure freq's up to around 1MHz. Also this analyzer came with the CCIR filter board in it. I wanted the "A wgt" filter so I built one and installed it in the optional filter location. I'll include the CCIR filter board in case you wanted it, but the A-wgt filter is still in place. I picked up a couple of NOS CLM-8500 opto resistors that are used in the tuning section of this analyzer. I installed one of them, I'll include the second one with the purchase. Its still sealed in its original pack.

I added a small cooling fan to the rear panel. I found when using this analyzer for lengthy periods that the covers would get extremely hot. After a few hours of running very hot the analyzer's performance would suffer and the THD readings would rise up from -102 to -103dB up to around - 97dB or so due to the heat. In the early units the power supply was in a separate box, but in the later production models like this one they put the power supply into the main case and eliminated the external power supply. This analyzer has very poor ventilation slots in it and doesn't cool well, when coupled with the internal power supply it gets hot when not actively cooled. Adding the cooling fan completely corrected that situation, this unit now runs at room temp all the time as long as the cooling fan is running.

Also this unit didn't have the battery in it when I got it. I added the wire harness and put a small UPS battery into the unit. I just put a different battery into it a couple of weeks ago that seems to be holding a good charge. I fully charged it and then let the unit sit for 20 min running on the battery and it was still showing about 50% of the "Batt OK" range on the meter. I think you can probably get a good 30min on this small battery without running it down too far. You could put a larger battery in and probably get well over an hour of battery life out of it. This is a great option to have in order to eliminate ground loop issues. Being able to unplug the 3501 from the wall while testing can eliminate a lot of noise issues on gear sensitive to ground loops.

This 3501 has a bit of meter fluctuation when operating and its most visible when operating in the -100dB range. If you run a 1kHz loopback test with the 30khz low pass filter active you'll get .0007 - .0008% THD+N. So the needle fluctuates typically within that range in the -100dB range. Activating the 400Hz HP filter will further drop the 1kHz THD to about .00065 - .00075%. When running a 20kHz loopback test this analyzer will show .00125% THD+N with the 30kHz low pass and 400Hz high pass filters active. Reading that in the -90dB range shows minimal meter fluctuation.

This is a very nice meter that's had most of the maintenance work performed on it and is ready to use.

This 3501 does NOT have the IMD option.

Price $375 + shipping + paypal (I also accept Zelle) I'll only ship to the continental US.

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QUAD 303 style output triples

Trying to understand the output stage, I have tried simulating the two triples as complementary sets and find that the npn-pnp-npn and pnp-npn-pnp arrangement is much worse behaved than the pnp-npn-npn and npn-pnp-pnp
The second arrangement, left hand side of the schematic has a lot less hard switching and high order distortion.
The original 303 used both structures to get away with an all npn output stage, but it was unbalanced with significant 2nd harmonic before feedback

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6.3 filament from 5vac winding

Hi All,
This is my first post to a forum so please bear with me.I found this idea in the book Tonnes of Tone by Kevin O'Conner and thought I would try running my 3 preamp tube filaments on 6vdc to see if it made a difference in the hum of the amp.The article stated it could run up to 5 preamp tubes on a 5vac 2amp winding.I am putting it into a tweed chassis and with it being a little tight I changed the bridge rectifier from a KBP602 to a BR104.I also changed the transistor from a 2n3005 to a TIP3005G.the circuit runs at 6.28 vdc with no load but drops to 4.2vdc when I connect a .45amp load.Any ideas on the problem would be greatly appreciated.Please see the attachment for the schematic.Thanks,Tom

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Linn LP12 Trampolin Kit

Hi, everybody out there,

this is my first post on this forum. I'm using a fully equipped LP12 as a main source for listening. This means: LP12, Aro, Armageddon, Cirkus-Kit, Trampolin-Kit, Benz Ruby 3 Cartridge.

I'm lookin for your experience with the Trampolin Kit. Is it useful, if one has a really rigid stand? Does it better the sound... or not...:xeye:

I'm very keen to read about your experiences.

Have a nice time.

Wolfgang

Re: Linn Cirkus bearing set

Re: Linn Cirkus bearing set

I wish to change my Linn LP12 to Cirkus but the Hong Kong dealer is selling me a full set that includes the spring, subchassis, arm board etc. Why do I need these since I already have them in my turntable? Is there a place that I can only buy the Cirkus bearing?

Is there an online source that I can buy Linn accessories at a reasonable price?

suggestions on how to dissipate heat on a snap-in capacitor that's NOT soldered to a PCB

Hi everyone,

I just read that capacitors produces heat and this heat needs to be dissipated. When installed in a PCB, this is not a problem as the copper traces can act as a PCB.

I want to do a simple unregulated power supply using point-to-point (think tube wiring). The most inexpensive capacitor I've seen within the capacitance required/desired is a snap-in.

Any ideas on how to dissipate the heat?

The capacitor will be mounted directly to the bottom metal plate of the chassis using clamps (with the capacitor "hanging" upside-down).

some ideas/thoughts that comes to mind:
  1. Perhaps I can use a heatsink grease between the "top" of the capacitor and metal plate to dissipate the heat? or maybe the copper wiring soldered to the pins is enough to dissipate the heat?
  2. My assumption with screw mount caps is that with a screw capacitor, I can use a copper plate to act as "PCB tracks" which would then act as heatsink. It would be easy to attach the copper plate to the capacitor because I can use a screw.
  3. Maybe there's no need to be concern at all?
Thanks in advance.

PS. I have not used snap-in or screw capacitors before. my experience is limited to using soldering (<4700uf and less) caps to PCBs.

switch mode power supply for good amplifiers

OK- I know the answer - don't. Good old power supplies are better, easier to work with, and can deliver all the clean power you need - in line with the experience Nelson Pass convey . And I am not doubting that this works - I have had a class A amplifier that consumed 500 watts, and I had absolutely no complaint with the sound.
However, I am living in Europe, and we start taking energy consumption seriously. So my question: Has not one single company specialised in making decent switch mode power supply for hifi? Benchmark claims that it is possible with their power amplifier. I am not talking about only using them for Class D amplifiers - is it a dream to use such a thing for one of the smaller Pass single ended class A ( such as 20watt). With the efficiency they have, a dream could be to have the good sound with only the use of what an old light bulb might consume.
Is this just a dream? I am not talking about a DIY thing, but a power supply someone made for DIY'ers.
Please tell me if this is just a dream - but I would be even more interested in coming to know some solutions that might be - maybe not perfect, but acceptable.

Indel transformer any good?

Hi,

Anyone has experience with Indel toroidal transformers? Are they any good? No buzzing?
I need a pair of 300VA 30-0-30V and these are very unexpensive - to good to be true? http://www.tme.eu/en/details/tst300w_2x30v/toroidal-transformers/indel/tst300016/

What about these from Talema? 55174-P1S2 TALEMA - Transformer: toroidal | TME - Electronic components

Should I buy any of these?

Thank you.

Using a passive preamp with icepower 50asx2se?

Hello folks, Pardon my noobish question. However Im building a icepower amp based on the 50asx2se. I would like to have volume control on the Amp but not sure what direction to go in. I was wondering if using a passive preamp such as the Nobsound NS-05p between my Dac a music fidelity V dac II and the power amp is a wise choice? Im told the input impedance of the icepower is low appx 8k. Now I have a few optins for volume control seeing I use Roon and can enable DSP volume to the Source but prefer not to. WHats my best option? My other option was I often run my Yamaha CA-1000 vintage integrated as a preamp as well. CUrrently using it with a TPA3255 Class D chip board in that manner. Is there an off the shelf input buffer board I can buy to install in the ice amp along with a volume pot? Or what of these mentioned options are the best for my situation?

Low Power Subwoofer Modeling

Hi all,

Forgive me if some of this is not correct, I'm new to designing loudspeakers and subs but I'm really eager to learn more. I've been dabbling with modeling software for about a week now and playing around with various drivers and enclosures to get a better idea of things.

The application is home theater with my primary interest, from a subwoofer duty being 20hz to 80hz. I'm not looking at this time to hit reference at 15hz or less or anything.

Anyhow, I got really interested in the awesome VBSS design (by MTG) and then went down the rabbit hole of looking for ways to build either efficient or sensitive speakers, or both really, and then use DSP to limit the driver. So I started modeling with inexpensive drivers in various cabinets and came up with my own variation of the idea with similar hardware, but instead of using high powered amps, I'm looking at it from the perspective of... could this run off 50 watts at 8ohms? This makes amplification a breeze. To build SPL, it would be done with several units. This may be flawed thinking, so please, let me know where I'm falling off the cliff if I am!

Here's what I'm currently thinking about and modeling:

Slot vented MDF based enclosure, 24" x 22" x 18.45" with a 20hz tuning frequency. Net internal volume is 4 cubic feet (taking into account the driver displacement, etc, maybe a little more for bracing). I originally had a larger cabinet but the driver excursion was getting out of hand. 20hz is chosen to get that high SPL output with minimal excursion from the driver, so that the woofer is only really having to stress around 30~35hz with its excursion (if I modeled it correctly).

I'm modeling with the GRS 18PT-8 18" Pro Driver (8ohm). It's only $70.

SuperBudget18_4cuf_20hz.jpg


Here's the driver excursion relative to xmax:

I applied a few filters to control the driver. A highpass filter at 17hz. A lowpass filter at 200hz, but this could be at 110~120hz, it won't matter much as I will crossover. PEQ +15db at 20hz with Q of 0.75 to boost the near port output without asking the driver to have high excursion while doing it (I think?). PEQ -8db centered on 55hz with Q of 1.4 to smooth out the peak that was there and further drop excursion. The resulting excursion model in this box at the intended signal input is graphed below, so that the driver doesn't exceed xmax until well under port tuning frequency which I will cut off.

18PT-8_4cuf_20hz_ConeExcursion.png


For the slot vent, it's 1.0" x 20.74" x 29.74" in this enclosure to produce the 20hz tuning frequency, but also to limit air velocity from the slot at the intended input signal so that it doesn't exceed 18, conventional wisdom being this will eliminate the chuffing sound.


18PT-8_4cuf_20hz_AirVelocity.png


Those models and filters in place, the following is the SPL graph result.

This is where things get sketchy maybe. I'm modeling this based on a 10 foot distance from the driver face to the listening position and an input of only 50 watts at 8 ohms. I know this is nothing outstanding, but for me this is interesting because for just 50 watts, I'm looking at a nice curve to start working with from just one sub and only 50 watts of power that will be very stable to run. The goal will be to build several of these, 4 of them to start. So the idea is that if I'm getting potentially 96db at 20hz and up, when I add the 2nd sub, I could expect to be close to 100db at 20hz, and add two more and get closer to 105db potentially at 20hz, before room gain (sealed room).

I already have a miniDSP HD 2x4 that I use, so I would use that to align the subs and produce the summation virtual sub and then EQ that for a gentle house curve, based on whatever the 20hz performance ends up at.

I already have an AudioSource AMP100 amp that does 50 watts into 8ohms, two channels, with a nice big power supply. These are inexpensive and pretty solid. I could add another for the 2nd pair of subs. I probably could get way cheaper amplifiers for this, but I'm not certain of quality in tiny class D amps around 50 watts into 8ohms out there with good quality output down to 20hz. I'm totally open to suggestions if you have them!

So end result would be 4 of these enclosures, each running at 50 watts max, for a very low total power draw running full tilt at all times if wanted, stable. Again, from the standpoint of 10 feet distance to the subs (they would be in a sealed room 10 feet from the listening position area) in the home theater room.

18PT-8_4cuf_20hz_SPL.png


If this is modeled properly, and will work (I have my doubts, which is why I'm asking!) the break down is:

Driver x 4 at $70 each, so $280
MDF, glue, screws, terminal binding posts, typical wire, x 4 - $200
Amp x 2 at $150 each, $300

About $780 for this project, unpainted. I would probably just black paint it matte or duratex type look, utilitarian.

Do you all think this is plausible?
Are the models ok or is something horribly wrong?

I do realize there are limits here, and that asking this system to do more than its max is not going to go anywhere. I modeled it for its max use and distance in the room for its purpose.

Any input appreciated.

Very best,

Bought a TAS5630 and instantly killed it - Chance for repair?

Hey people,

no excuses, don't know how I managed to do this, but I connected the 12V line to the amp with reversed polarity (yes, it's even printed on the pcb not to do this). While waiting for a suitable smps, I tried the amp with my bench psu which could deliver 50V, but only around 100VA, and everything went fine. As the smps arrived, I made everything fitting in the case underneath the sub, and installed two 120mm fans for an appropriate airflow, also. This was quite some work to do, including many hours of painting-sanding-painting-sanding-pain... .

Whatever, I switched it on, and the 12V wire went up in smoke. As hope dies last, and the two green led's were still lighting, I connected everything correctly and gave it a 2nd try. I switched it off as soon as the small blue spark showed at "D2".

Ok, it's dead. But I don't want to bury it, if there is a maybe a chance to fix it. The problem, I'm not the worst with the soldering iron, but I'm just a mechanic.
The green lights still light when 12V are attached, and just by looking at it, I do not see burned or "exploded" parts. Just U5, a LM317G voltage regulator looks a little strange.

What could I Do, what could I try, to maybe save this amp?
I've got no oscilloscope, just a multimeter.

best regards
Jochen

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Any tips for designing/building low noise preamps ?

I have been working on a diy audio mixer based on ne5532 opamps with auxiliary output/input, panning and baxandall tone control.
Here is the circuit of one of the inputs:
in PCB.png

(+-12v supply, 100nF on each Vpin of the opamps) (this "input module" will be duplicated for each chanel I make and all chanels get mixed in other circuit).

I made the PCB and everything worked fine (except the tone pots where inverted whoops :spin:). However the preamp adds to much noise to the signal and makes it pretty unusable for instrument-level inputs.

The noise (hiss) gets amplified when i raise the gain. And gets worse When treble pot is boosted... It also has some hum but i think thats because i havent shielded it yet.
Maybe you, the opamp-gurus, could give me some design tips on how to improve signal/noise ratio on the preamp. Or modifications to improve the rest of the circuit??

3D Holographic Imaging?

I intend to make a similar post on the tube forum. I hope that is acceptable.

Hello! I am trying to decide what sort of preamplifier / amplifier to choose for my system, and I have heard that tube amps do 3D holographic soundstaging and imaging better than solid state. Is there any truth to this?

This 3D immersive holographic sound is my biggest priority for my decision here, so would I be better off with tubes? If so should I do tube preamp or power amp? (I would prefer not to do both, and ideally neither)

I don't like how inefficient tubes are, I don't like that you have to replace them all the time, I don't like that they heat up rooms. I know they measure poorly but I don't care about that really. They sure do look cool though

Anyways, I will do whatever it takes to get the most enveloping imaging possible, but my fingers are crossed this doesn't mean I have to buy tubes. What do you think? Thanks!

Carver TFM-25 help

I am trying to get a Carver TFM-25 up and running again but it keeps going into protection mode only when a signal is applied. I plan on doing modifications per order of a service bulletin included in the service manual I attached below but I need to sort out the main problem first.

I am looking for someone to shove me in the right direction of what to look for, I am more familiar with hollow state technology. Plus this amp's topology is different than what I am used to seeing.

Thanks

Tascam MH-8 Headphone amp

I have two Tascam MH-8 headphone amplifiers. One of them has some problems I would like to address. Generally, it is working but there are some issues.

The unit powers up and there is sound, aside for a couple channels with broken pots that I need to replace. The primary issue is a large section of the main board that looks cooked under 2 rows of 32 transistors each and a row of 32 resistors.

I'm assuming the problem is the transistors and not the resistors (180Ω 5% 3W). Is this a safe assumption?

The first row of 32 transistors alternates between C1815 and A1015, there are 16 of each. From what I understand, these are complimentary transistors.

The second row of 32 alternates between C2236 and A966, again, these are complimentary.

The other MH-8 has a much higher serial number to compare to. The main board on this unit is not burnt and 3 of the 4 different transistor types have different part numbers on this later unit.

All A1015's have been replaced with A1266 GR
All C2236's have been replaced with C3205 YK 743 KTC?
All A966's have been replaced with A1273 YK 805

After doing some research, all of these are legitimate replacements for their predecessors. The C3205 and A1273 are in a different package than the A1015 and C2236 which are in a TO-226 package. I'm not sure what it is. I can't find anything like it in any package charts I have looked at. Does this even matter?

Also, the newer unit has the exact same 3 watt resistors, same value and tolerance, this is largely why I am discounting them as the source of the problem.

While the unit does work, obviously something isn't right given the blackened board and it appears that Tascam realized this and substituted some of the transistors in newer units. While I'm replacing the broken pots I thought I would replace all or most of these transistors. Would it be a good idea to replace all of the A1015, C2236 and A966 devices with A1266, C3205 and A1273 respectively as is the case with the newer MH-8? Would it also be a good idea to replace the C1815's with new C1815's since they've probably been through hell?

One other difference between the 2 units in this area of the main board is another row of 16 resistors. On the "bad" unit, these are 1/8 watt 2.7kΩ 5% and on the good unit, they are 1/8th watt 2.7kΩ 2%. See R032 & R044 in both pics above. Should I change these from 5% to 2%?

Finally, if this is a good plan, how would I choose between KT and 2S variants of all of these transistors since apparently either is acceptable? I don't really understand the difference. For example, 2SC3205 vs. KTC3205.

I would appreciate any input on this

JVC AX 440 source select problem

Hello.
Amplifier JVC AX 450.
Impossible to select source.
Any red led on front panel.
On J108 pin 1 ....+14v ok.
Pin 2 ......-19v,not -14.6.
I think IC101 is dead.
All voltages for power amplifier are ok.
Relay click.

Need help.

Service manual
https://elektrotanya.com/jvc_ax-440bk_sm.pdf/download.html

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WARNING: About the DUST!

Administrator really should make this thread a "sticky"

My "high-end" neighbor likes to bring me his new found treasures that require servicing.
It's not always a pleasant job of course.
And this one job I'm currently doing is the focus of this thread.

It concerns vintage equipment that has a known, dangerous, and deadly element known as Cadmuim.
It was used in many things as a plating on metal parts, and perhaps you've seen a white or yellowish powder on old equipment.
Chassis, speakers, and other components are all affected.
It MUST be CAREFULLY removed.
Cadmuim is as bad as Asbestos if you breathe it.
A mask, gloves, and eye protection is mandatory.
And it has to be done OUT-doors, carefully.
I won't go into the whole procedure, you can look it up for yourself.

This is a close-up photo of the 1964-ish Thorens TD 124 motor assembly on my bench that was seized-up but serviceable.
It's gonna be a messy job, most of the turntable's parts are also contaminated with the white powder too.

cadmium dust.JPG

Hifonics BXi 6000D - Drive cuts out

The Amp is working at the start, 13,5V 2,5A, then after some time the drive dies, consumption drops to 1,5A.

The 12V Regulator only put out 11,88V, the new one does 12,11V. That didn´t solve it. +/-5V is there and doesn´t go down as the drive dies.

I desoldered the Driver-Board and put new IC´s and transistors in. LM211, TL072C and LM293.

Still the same, it takes longer than at the beginning, where it shutdown after a few seconds.

What could cause this behaviour? The Inductor beads have around 1Ohm.

Did someone have this kind of failure in the past?

Thank you for your answers.

Design around the mini earthquake and lp210pa

I would like to design a portable boombox around theMini earthquake subwoofer and the lp210pa plate amplifier. I would like some feedback on the different ways to go about it.
1) feed the the plate amp a stereo signal and add 2 fullrange speakers to the output. I'm thinking some efficient smallish 4ohm speakers should be preferred as they should be better at high range frequencies and the mini earthquake takes care of the low range. Am I correct? No crossover needed as the amp has a lpf and a hpf that is fixed at 100 Hz 6 dB/octave
2) feed the plate amp stereo signal and use midrange woofer and tweeter to left and right output. So here I should go for 8ohm speakers and tweeters I guess and use a passive crossover between mid and tweeter. I'm guessing this would make the whole system less efficient so maybe not the best solution for a battery powered system.
3) feed the plate amp mono signal add midrange to left output and a tweeter to right output. I got this idea from the dinas speakers. I guess this would play louder I wouldn't get a high-fi stereo sound but I doubt stereo really matters when listening outside with around a campfire or such. Would need a crossover to the tweeter again.
4) other suggestions are more then welcome.

This would be my first project so I'd like to keep somewhat cheap and use the KISS method (Keep It Simple Stupid!). The sound doesn't have to be extraordinary but a nice sound should be good enough for the girls I go out with. I know my way around a soldering iron and basic electronic stuff but audio is kinda new to me.

EMI noise on an I2S DAC only with GPIO PSU

If I power from a Pi USB PSU my DAC is quiet and also so is the boot.
I am trying to power from a 24v PSU with a 5v step down on GPIO and tried all sorts of EMI filters, Wide Input SHIM from Pimoroni. Its EMI in fact you can almost hear the SoC at work with a background noise that often sounds like an old analogue modem.
Is it because on the same 24v DC that powers a 100 watt amp it creates a ground loop as at whatever stage I add EMI filters to the DC supply I can not seem to get rid of noise that seems to be generated by the Pi unless I use a seperate PSU for amp and Pi. Which sort of negates my idea of a neat single 24v DC supply to a small enclosure for the Amp and a step down to power the Pi. Tried linear regs, a couple of different bucks and the Pimoroni psu shim with emi filters from input to the dac to pi power input and still noise.
Take out the buck and with a standard Pi PSU powering the PI with the same 24vdc on the amp and all is lovely.
I am scratching my head really but thinking maybe the GND in the audio out of the DAC is creating a possible ground loop that maybe with the 2x PSU isolation doesn't exist. Anyone got any ideas?

Clock buffer - using NOT or logic gates for less distortion

I saw an interesting article on clock buffers - specifically the impact of opamps on clock skew and jitter versus using series of NOT/inverter gates. The article demonstrated that the NOT gates (perhaps due to being an opamp Schmitt trigger configuration?) having less slew and less jitter. The result is that a series of NOT gates performed better than an opamp as a buffer.

I'll try to find the article - IIRC it was a Texas Instruments article. However has anyone tried/used this?

Setting up a passive PA system

Hi,
I am new to this forum. I need some help setting up a PA system. I have tried to look for some decent info online but it generally for powered speakers etc. which I do not want to use. I have the following components.

Xenyx 16 channel mixer
BSS 966 EQ
DBX 234 xl crossover
DBX limiter (not totally required just yet but I think this is set up as insert but not sure)
Behringer NX3000
and a Wild Thang 200 amp lol
2 Yamaha 12 inch tops
and 2 sub zero 15" subs.

I have had connected many different ways. I think I want to run it stereo but I see the benefits of running mono. I am setting it up primarily for my sons band and as a party PA. Any links or advice would be highly appreciated. Thanks again.
D

Elektor's CD Buffer + low pass Filter PCL86/ECL86 (Haas) - Conversion to a Preamp ?

The main application of this unity gain buffer device is the reducing of harsh and crispy sound character of various cd players resp. D/A converters.
My idea is now to use this device as a unity gain pre-amp for driving long signal cables to mono power amplifier inputs.
The retrofit of a good potentiometer shouldn't be an issue.

The question is, what is the aim of the serial input capacitor which have only 22pF.

In the attachment the description of the whole project include schematics.

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Audible Noise Transformer Core

I have built a small, isolated DC-DC supply. It's basically a flyback with optically coupled feedback. The transformer is planar type, and runs primarily in CCM. The problem is that the core rattles, sings, at light loads - its audible and easily heard. The PWM chip has a light-load feature where it skips as needed....this is when the core rattles. Without skipping (either under a heavier load or fooling the chip with a high value current sense resistor), the loop is very stable, and the core does not rattle at all.

My ears are not great, but listening to the pitch seems to be at about the same frequency as the bursts during light-load. So - I'm pretty sure the skipping feature is causing the core to rattle away.

Does anyone have an idea on how to fix this?

1kVA transformer to 33000uF capacitors (and other high power suggestions)

thinking of getting a higher transformer rating 2 power both right/left channels (parallel LM3886s) because

  • cheaper (looking at mouser, the cheapest 1KVA is only $50USD more than 500VA)
  • lower footprint

Is there anything I need to be concern? and perhaps you have suggestions for these concerns?

Also looking for suggestions for recommendations for such high power supply. (example: like heatsinking the diodes)

Thanks in advance

A Karlson Compendium - Part One - "A New Approach in Loudspeaker Enclosures"

A Karlson Compendium - Part One - "A New Approach in Loudspeaker Enclosures"

John Edward Karlson (Feb. 4 1910 - Jan. 18, 1973) was: an inventor, radar engineer, patent holder and co-founder, along with the late Wayne Green,
of a loudspeaker cabinet manufacturing company, Karlson Associates Imc., Brooklyn New York, and best known for his first commercial cabinet (now known
As “K15”.). K15’s prototype was built and tested in the summer of 1951, and introduced to the public at the fall 1952 HiFi show at The Hotel New Yorker, which
featured many of the luminaries of that golden age of Hi-Fi.

K15 was designed primarily for co-axial and full-range speakers of 15 inch size, and 12 inch speaker adapters were available. K15 has been ridiculed, and
touted one of the worst loudspeaker designs in history. It’s claims of flat response to the nether regions of bass are not true. What is true is that its capable of
a “musical” presentation when used with favorable drivers and also capable of agile bass at high peak amplitudes with very little cone movement. That is not apparent
from a simple graph. Over a certain region, horizontal polars can be improved vs a direct radiator. and distortion often than compromised mid bass and bass horns of equivalent
bulk.

As Karlson’s first “Acoustic Transducer”s article states, the tilted baffle forms a wedge shaped chamber and the tapering in volume vs widening of the slot, less energy storage than with a box cavity. Also, the upward tilt of the baffle puts some of the treble lobes through a tapered diffraction slot.

The patent also states, the greater the baffle tilt, the worse
the effect upon transient response so for a given loudspeaker there may be an optimum cavity, baffle tilt, aperture taper, etc.

Also, the greater the baffle tilt, the more "reverb" effect.

K15, loaded with Electro-Voice’s 15TRX speaker, provided sound for a number of pavilion and exhibit including Disney at the 1964 through1965 World’s Fair.

To my knowledge K15 was produced basically without change other than minor port and shelf gap adjustments.

K15, btw, was not the largest regular production model. Karlson also had a K18 console with upper compartment for midrange and treble drivers/horns.

In the fall of 1954, a smaller model for 12 inch (and 8”, 10 with adapter boards) the “Karlson Twelve” was introduced. At that time it was known as the “Karlsonette” as there were only two models. This early “K12” had a reversible port panel, and three position moveable bar on the back panel to adjust the area of the rear shelf lowpass gap. A year later in 1955, the tiny Karlson Eight was introduced.

1956 brought the diminutive KR5 “Rocket” speaker which resembled a standard pyramid shaped metronome. KR5 became the inspiration for Karlson’s “Asymmetric Projector” speakers with supposed “clam” shaped dispersion pattern - - affectionately known now as “klams”. These projector speakers were manufactured both by Karlson, and under license by Karlson’s good friend, Jess Oliver.

In this part is the 1952 Audio Engineering Magazine article

(Since I cannot go back and edit after 20 minutes to make a good table of contents, I’ll present this bit of history first - then plans in the next segment for the “heritage” lineup of Karlson Ultra-Fidelity models. - Then, hopefully links for the other Ks including GregB's Karlsonator series, and many ongoing threads by XRK971)

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Suggestion: Add a new subforum named "DSP coding & software tech"

As the DSP based crossover and room correction became a standard configuration in professional monitoring speakers, And high performance DSP chips gives us a new way to do something beyond the digital filter of a chip DAC.I do believe that software defined DSP will be the future of audio. To carry on the dreams to build the devices which would exceeding the base level of audio industry, we may need a SPECIEL subforum for the one who is good at writing codes and algorithm.

At current forums, the DSP focused thread can be placed in loudspeakers-multiway if its a DSP Crossover powered active speaker; or it will be in the source&line - digital line level if someone made a project of DSP chip based external digital filter for the DAC. Or even it can be find in the PC based subforum if it was running on a PC software and then send the processed data to a DAC.

We need coding guys assembly HERE in a right place, for the future of DIY audio device.
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For Sale SB Acoustics SB23NBACS 45-8 2pcs NEW

I am offering for sale 2 pieces of brand new SB Acoustics 8 inch woofers SB23NBACS45-8. These are black aluminium 8 ohms. Spend one year in garage and that's all. Opened only to check whether they are ok and to take photos for ad here.

Never played, mounted to any kind of baffle or soldered.

Price for both 150 EUR or USD as they are the same now. Shipping within EU 30 EUR. Will accept buyer's courier upon previous agreement. For shipping outside of EU please get in touch.

Paid on PayPal.

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New member from Sintra, Portugal

Hi everyone,

I've been a lurker of this forum for years, and now I've decided to be more actively participating.

As a bit of background, with the help of a friend I've built my own Kondo Ongaku homage amplifier (not really a clone).

I did all the 3d design myself and built the chassis out of 3mm copper plates using my CNC, I'm attaching a few 3D renders and the finalized project 🙂

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GM70 SE amp project

Hey guys

Actually two of my friends and I are working on a single ended integrated amplifier so we thought why not to write about it here in order to use group wisdom. :idea:

OPT and power transformers are made by a friend whos job is pretty good in building tube amplifiers:

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he suggested to use 6n6/6H6 as input tube and two 6E5P Russian tubes do drive one GM70 but without any further details. here are PSU and amplifier schematic I got so far:

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I'm not sure about using 6N6/6H6 and 6E5P. I may consider other tubes if I have access to. any idea is much appreciated.
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Voltage limited or amp limited, 4ohm vs 8ohm.

Hello, I've been using a pair of Dayton Audio ND90-8 with a wondom, tpa3116d2 amp, running from a 5s battery pack 15-21 volts. The amp should be able to output around 30wats on 24v, the speaker can handle 20watts rms. I feel like many times i am not getting the max output out of these drivers, nor i am able to hear them distort or clip. I was thinking that the voltage of the battery is not enough to fully power these drivers. Would changing to the 4ohm version of the same driver increase the output ?
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