Hi guys, I'm actually planning on building my first speaker, and on the electronic site I use to command the electronics componants I found a bommer (22-200Hz) which seems quite nice and is cheap (I have a low budget ^^). I was wondering if you could help me get informations on this boomer because appart from another link I haven't found anything else about it.

First link :
https://www.gotronic.fr/art-boomer-polypro-wd8-130-31530.htm
Second link :
https://www.e44.com/audio/haut-parl...e-polypropylene-130mm-50w-89db-WRB130SQS.html

Thank you !
Axel

I have a Rotel Integrated Amp, RA-985BX. I bought it new in 1996 or so and thought it could use a freshening up. I found the schematic and identified several smaller value -- 4.7uf, 10uf -- electrolytics. I thought I would replace them with Wima 5mm film caps. Before ordering replacements, I took the covers off. I also wanted to check the ESR on the filter caps in case I needed to order those as well. I figured since I had the covers off, I would preview the project to make sure all of the smaller electros were accessible. Lo and behold they all measure fine with low ESR readings and they are Rubycon Black Gates, which I guess Rotel used at the time as stock.

Thus, I am looking for opinions -- should I swap the BlackGates for Wimas, or leave things alone?

Thanks

Hello everyone. What is the name of this type of amplifier? Received good parameters in the simulator. Please critique.

Looking for suitable replacement FETs to match to replace this double j-fet package? It's a differential pair for my phono mm card in a Sansui AU-X11. Not having any luck?
2N5247 was listed as a good sub, but it's long gone now too?

I am trying to locate the root cause of the buzzing audio sound I am getting when the volume is turned up fairly high with no signal. I have replaced 3 3900 Uf filter caps on the PS board but that did not resolve the issue. Has anyone ran across this? Does anyone have schematics?

Thanks in advance.

I'm working on a portable amp project and am wondering about the feasibility of using a dc voltage multiplier so that I might reduce the size (and cost) of the battery pack.

The most recent amp I've built is a class D unit using the TPA3110D2 from TI. On other portable stereo applications, I've used pretty large battery packs (i.e. 12 NiMH cells to generate 14.4v) But for this next project I'd like to go a bit smaller.

The TPA3110D2 can be powered by as little as 8V (and as much as 26V).

What I'd like to try would be a 3 cell (3.6V) or 4 cell (4.8V) pack, so that the battery could be recharged from a USB port.

The problem here is getting the voltage up to the minimum 8 volts required by the amp chip. Also, if I recall correctly, the chip drew around 0.5 amps when set to a normal listening volume. What's the simplest solution? Just browsing around digikey revealed several dc-dc step-up converters and charge pumps, etc. The only problem was that they were all rated for very low current application (i.e. tens to a few hundred milliamps).

I realize that using a smaller pack and multiplying the voltage will result in limited usable time per charge, but it seems like it might be worth a shot. The 12 cell NiMH packs are great for battery-life, but they're a little big and expensive.

Thanks!
-Chad

I purchased this oscilloscope about 2 years ago and have used it occasionally. I think I turned it on twice in the last 6 months. Time to clear out my stuff.
Comes with 2 original probes and power cord.
Works as new.
I have the original packing materials.
I'm not sure if I have a print manual.
https://www.keysight.com/us/en/assets/7018-05520/data-sheets/5992-1965.pdf

SOLD

Hi,
as I move back to Germany in the beginning of February, I want to sell my DAC, as it otherwise would sit 3-4 months in custom waiting for clearance:

Schiit Yggrasil, silver
Multibit DAC with Closed-Form Filter,
Analog 2 Boards, Gen5 USB, (Newest Version)
EU plug, 220-240V (50/60Hz)

I bought the DAC in May 2018, and it came with 5 years of warranty, so more than 3 years are left.
The DAC is in like new condition.
You can have a listen to it in Sao Paulo.

As the DAC is in very good condition, has >3 years of warranty, I would like to have 2400€ for it.
Cheers Matthias

This has been floating around my computer for a while and I'm just not sure it's an Apex design. As you can see, the schematic is missing information and a couple of connection points. There's also a couple of pcb's that do roughly match up with the schematic, but are different from each other. Anyway, was hoping someone might know the information on this circuit. Thanks.

I change plan of using this https://www.hypex.nl/product/fusionamp-fa251/155

to this https://www.sweetwater.com/store/detail/XLS1002--crown-xls-1002-power-amplifier/reviews and this
https://www.minidsp.com/products/minidsp-in-a-box/minidsp-2x4-hd

Advice welcome.

I have one sub, with plans to grow it to 4. The mini will have me covered. and I read it will go to 10 hz.

I have a feeling the amp crossover directly to subwoofer won't be enough. Some boost is necessary.

The pairing looks capable and its budget conscious to me. These days most welcome.


I want to built build one simple micro cube (sealed) every couple weeks until totaling four. A pair of 1002 xls should easily power them, the minidsp will filter just whats needed. I feel like playing with 8 inch minis because I already had one nice one to start with. A single start up 15" jbl experiment will be later down the road. If subwoofer play stays in action. I had intentions to build a two channel that simple and sounds good. Now it could use some bass. It still sounds great, the novelty soon wears off. Theres that plus I tested a sub with the system, it sold me on the whole idea in an instant.

Digital Voltage readout is not working, digging deeper I came across a few random BJTs testing bad in circuit, I’ve tried looking them up online but can not find out which these are, each pair of PNP & NPN is marked “D9D” and “B9D”

any help identifying these or links to a source that can help me identify these and others would be very much appreciated.

Ty 🖖🏼

Glassware ACF-2, fully populated except for output coupling caps. Currently configured for 6.3 Volt heaters (6922, 6fq7, etc) with 6.3 VAC heater input. Includes User Guide and various extra resistors for R2, R4, R5 and R7. Asking $60 plus shipping to US and Canada.

I'm building an M2X amp. I need a pair of speaker posts, but searching for "speaker post", "speaker terminal", "speaker jack" on mouser, digikey, and don audio, isn't giving me anything useful.

The ones in the amp camp amp would be fine, see step 4
https://guides.diyaudio.com/Guide/Amp+Camp+Amp+V1.6+Build+Guide/5?lang=en#s132

if someone has a brand that they think is better, I'm all ears.

Downsizing our home. Designing open baffle speakers for a smallish 13 ’x 14’ room. Considering the Lii Silver 10s or TB W8-1772s. Anyone compared these in an OB? I know their Qts is a bit low, but they’ll be augmented by OB 12” powered servo subs mounted on the same baffle. They'll be powered by a (1.5 - 2 watt) 45 SET amp.

Both the Lii Silver 10s & TB W8-1772s have good reputations, but different strengths & weaknesses. I’ve not heard either or been able to locate any direct comparisons on the net. Can anyone shed some light on these 2 in an open baffle with a flea amp? Thanks.

There is demand for Aluminum knob .
many countries dont have it online or offline

So i have created a metalknob with diy method .

-no laathe or solid Aluminum needed
-just metal scissor and dremel
some super glue,putty ,silver powder

process is easy to understand from pics

An alu- L shaped braket was cut for outer and top sheet of Aluminum

paper based lower former is made with glue.

make the metal surface rough.
glue top plate
then glue peripheri with caution
lastly you make 2holes for end fixof periphery plate.

use resin or strong super glue .
All will be done with small gap at the edge.
fillthe cap with putty+silvepowder or paint.

let it dry.
final look will be solid metal
--
now we need tomake it heavy
we can use cement fill half and use a epoxyputty to make shaft hole.
i will give more detail on how to do shaft hole in next posts.

(it is for people in need ...whoever can buy online they can skip this)

I have a hd750.1 with and few outputs shorted and the power supply torrid raised off the board. In a few of these I have found that the torrid had broken completely off repaied them and the amplifier worked. This one has a open or burnt resistor directly behind the torrid R592 I need the value of this resistor it's defaced so I can not make it out.

I am considering upgrading op amps in my lm 502 dac. However the dac has two selectabel outputs: transistor and tube. Does any one know if the op amps are in the commen path of the two outputs ore only the transistor output?

Jason, Gianluca & Co.:

What is the height of a baseplate for a Dissipante chassis? I am planning on building a Wolverine amplifier in a 3U 400mm Dissipante chassis and will use a baseplate (edges down, flat surface on top). The Wolverine uses a variant of the UMS hole pattern (which HiFi2000 will be asked drill into the heatsinks) and I would like to verify that the distance between the top of the baseplate and the center of the lowest drill holes in the UMS hole pattern is large enough to fit the Wolverine's power transistors (it appears a minimum distance of about 7mm is required when insulators are taken into consideration).

Regards,
Scott

I've been renovating a Quad 405 for a couple of days. Recapped it, installed a OPA604's, changed the D1 and D2 diodes and lowered sensitivity. Installed the boards and did some initial test, everything looked fine. DC offset sat at -0.8 mV and the other board at 1.6 mV. I let it sit idling for an hour yesterday evening. Plugged it in today and let it idle for a while, again DC offset looked fine on both channels. Moved the unit to test with a pair of speakers, but before that I thought I'd measure DC offset a final time. Plugged the multimeter to the left channel, set it at mV and turned the amplifier on. The DMM immediately went OL, and I heard a pop from the amplifier. Turned it off, removed the hood and smoke was coming out from it. Was sure I had managed to short circuit it with the DMM, but I had not it turns out. R22, D5, Tr4, Tr5 and Tr3 have all gone up in smoke. R35 looks cooked too, Any ideas what would cause this? I've checked my soldering more than once, no solder bridges, no cold solder joints. Everything is installed with the right polarity. I feel really bummed out about this to be honest. The board number is 12368 ISS 9. EDIT: I see now when inspecting the board that R35 has a cold solder joint, would that cause these components to go up in smoke?

Two TAD 1 inch drivers in very good condition.
Pictures, measurements on request.
Price EUR 1500,-- for the pair excluding shipment costs.

Do you live in a Spanish speaking country? What do you locally call speakers? I thought the proper word was Altovoz. But here all the shops call them Bocina, which I thought meant megaphone or horn. I'm so used to Loudspeaker and Haut Parleur that Altavoz seems more correct. Confused. 😕

This might seem like a strange question.

Say I fill up plastic soda bottle with water and cover my walls with them.

Does it primarily act as a sound reflector?

Would it resonate or trap certain frequency?

Hello

I have not found anything about the location of the terminal cup. Should it be placed under the sound damping felt or in an area without felt?
I am looking to build this.

Thanks

Is it possible to add whole threads to an ignore list?

I have no interest in threads about audiophile this, cable that, sonic properties, Bybee quackery, or any of these types of subjects. As they tend to be popular (for reasons unknown to me), can it be made possible to have an Ignore Thread list?

Got one of these with a fritzed power tranny. Anyone know what the rail voltage (DC) or raw output voltage (AC) of the transformer is. Simple single winding with CT so should be able to find an RS or E14 candidate.

HI all. I just registered for this site and am new to guitar pedal building hobby. Partly for myself, and partly for my daughter and her band to try out new sounds. I am practicing good soldering technique and learning breadboarding and schematic reading. I enjoy the research, parts hunt, soldering, and assembly, but not intending to make my own PCBs. I bought a few pedal PCBs from online vendors.

Anyway, my question has to do with a broken amp I recently bought. It's a Fender Champion 30 (non-DSP), from the mid-late 90's. It's a nice looking cabinet with a 10" speaker, and I would love to use it as my test platform while breadboarding or building pedals. So really just want a nice clean sound to use as a pedal platform.

I had typed up a few paragraphs of what I went through in trying to diagnose what's wrong with the amp, but it's besides the point. I found that almost every pot solder joint was broken and the PCB is a bit warped and flimsy and the traces very fragile. There is evidence of previous (attempted?) repairs. Given that the IC (TD1514A) and plastic PCB-mounted pots are long since discontinued and impossible to find, I think I'd rather put the effort into replacing the PCB with something better.

Specifically, I am interested in using Rod Elliot's pre-amp and power board PCBs from 100 Watt Guitar Amp (Mk II), along with the Fender cabinet, 8ohm speaker, and transformer, using threaded metal jacks and pots mounted to the faceplate. The 100W is certainly overkill for my need. I'd be happy with 20W-50W, but that leads me to a couple of questions about his project.

A couple of initial questions. He suggests using a toroidal transformer, but that a conventional transformer could be used if it supplies no more the 25-0-25 output. According to the Fender service manual schematic, the one I have (Fender part 033613) should be providing 20.3-0-20.3. However he also says "The transformer rating should be 150VA (3A) minimum" and mine appears to be 120VA (1A/250V 5mm fuse). In some cases he says you can substitute this or that, with an impact on the overall output, but I am not so well versed in electronics. In this case he clearly states a minimum, so I'll need to find a new transformer? Also, for the speaker, the project is designed for 4ohm output, but could I use the old 8ohm speaker? (please school me, I am trying to learn)

Any thoughts, gotchas, or better alternatives? Will this work? Many thanks for any input,
Ken

New hum- any ideas?

I built the AJ over a year ago (2 maybe? can't track pandemic time anymore...) and have been enjoying it daily since. Last night, while it was on, I unplugged it from a source, and it make a loud noise. I now notice a hum in one channel, that wasn't there in the past. It's pretty loud- I can hear it during quieter music passages (or dialogue- I use it for my TV sound system).

I switched L and R speakers- seems like it's the amp. The hum is less when the that channel's input is disconnected.

Any ideas on what could've happened? I had followed many of the suggestions to reduce hum- balanced XLR inputs, short and twisted lead pairs, input lines kept away from power, etc. etc.

Thanks!

Hi All,
I'm having trouble finding transistor replacements for the blazing fast drivers (200Mhz) on the stasis 3. Their models are 2SA1112 and 2SC2592. Any suggestions or substitutes would be greatly appreciated. Thank You.

New member and working a pair of Carreras. So far so good. Will post some build notes and pics soon.

Hello, I have an Akai am-u33 amp that has a problem.
When I bought it, I noticed a crackling sound coming from the speakers. After the logical tests (speakers ok, input source irrelevant, thorough cleaning of all pots and switches) the problem located in the preamp section of the amp (one channel worse than the other). An inspection for solder joints problem didn't solve anything.

My first decision was to recap the amp (electrolytic only), starting with the preamp section. During testing and probing for faulty parts and before the recapping process, the unit stopped working. I proceeded with the recap anyway (a merely 3euro cost) and now the situation is as follows:

The unit has new electrolytic caps in the preamp section.
The power transformer works great and the power supply pcb board delivers as expected. The unit powers up and the input source indicator lights work just fine.
BUT... no sound at all! The headphone output is also dead.
I tried to use the preamp and power sections independently... NO luck...
And by dead, I mean dead silent. Absolutely no sound at all, not even a hiss.

Any thought's what to look for? Where to look first?

Login to view embedded media Adding more capacitance to an amplifier seems like a good idea.
However the more capacitance the more the current spike for less time.

I'm trying to contact John Lonczak who showed his Tannoy line arrays at BAF19. Any help would be appreciated

Thanks

Bob

​

Hello again … .. I have a problem that I noticed these days, I do not know if I had it or now I saw it ,,, first I have a marshall jcm800 clone where I recently did some mods .. so what is the problem .. without having a cable at the input. when I raise the master volume it makes a hum. not possible but noticeably understandable and the stronger the master volume, the stronger it becomes ..I tried and removed a tube from the pre amp section and it sounds absolutely nothing ,,, this means that the problem has to do with the preamp and not with power section α I also noticed that of the 3 tubes of the preamplifier, one does not light well enough (in the filaments) ie while the other two seem to light up strongly, this one does not light well enough)I change the position of tubes and the poor light have the same tube .. .. and something else .. if I connect the guitar and turn up the master volume while I have turned off the guitar potentiometer, again the buzzer sounds loudly ..to emphasize that the mod I did was to put cathode bypass capacitor to cold clipper .. these ,, I just said to ask for your help before I open it once more ..and something else . I can’t find 12ax7 to test other tubes , here in Greece because you know the Ukraine war ..thank you

I am currently looking into the possibility for a small portable box for voice amplification.

It doesn't need to go lower then say 150Hz and cover the vocal range.
However I don't want it to be a harsh megaphone either.

For the driver I was thinking about using the B&C 6PEV13.
Can be used in a small closed box or a small reflex tuned at 137Hz. Don't know if the reflex would be a good idea tough.
other ideas are welcome but High efficiency is key here.

As an amplifier I am looking around some solutions. Dayton has some nice modules etc.
For batteries I'm gonna use a battery board from dayton or the like with 18650batteries.

The biggest issue I see is for getting a balanced microphone input.
The voltage would be +24v (from batteries) so making a small preamp that can work on an asymmetric supply is a challenge.
One solution could be using an input transformer and an opamp for this but I think it's a little bit overkill for this application.
Would be better If I could get an electronic balanced input. INA217 comes to mind but using an asymmetric supply this is tricky.
I also didn't found a small mic preamp board that I can use.
All ideas are welcome.

I would make a small cube in wood where everything would fit in.
Maybe an extra audio input or a bt connection.

I see it on internet
Just curious what speaker is this

Here is some information regarding the GAS Thalia 1. Hope it helps someone out.

As always, send me a pm if you need something.

If I can't get my 2 Kenwood KD 990/7010 decks to function, they are effectively the same, does anyone know a proven repair specialist in the EU preferably. I really don't want to entertain another D/D. They come with an excellent and easy to set up gimbal arm.

CAN SOMONE SEND ME A YAMAHA EMX5026CF SCHEMATIC DIAGRAM PLEEEASE ?

Hello - this is more of a loose curiosity question for future experimenting.

Is anyone able to site a hi fi tube amp design/model that was known for having unusually high output power but also somewhat unacceptable distortion?

Thanks. I realize this is a very indefinitive question but, would like to see if there are any models of amps or topologies that come to mind. This is for experimenting with a variety of instruments that are shown to benefit from a more hi fi presentation but, have proved to not sound too great through guitar amp type topologies.

Thank you,
Phil D.

I'd like to upgrade some of the parts for my stock Dynaco ST-70. Values are easy to find, but not necessarily ratings, especially for resistors. I'd like to replace the two 10K bias resistors (the pots seem fine). These seem like they might be 2W but i can't be sure.

A bigger wish would be to find a list of all parts with ratings. If anyone has seen such a thing could you point me to it?

The thread is dedicated to AP products.

Cheers,

Hi,
After many year of service, I am upgrading my Beard P100 power amp. I will be installing ClarityCap SA series 0.1uF bypass capacitors on the power suply of both channels and will be replacing the DC coupling caps between the tube amplification stages to ClarityCap SA series caps. One issue I have is that the capacitors between the first and second amplification stage is 0.022uF. I could not find a ClarityCap SA of the same value. Can I replace the 0.022uF caps with 0.1uF caps instead. What would be the effect of such a change?

Are there any other changes you would recomend?

thanks
Ronen

Hi all,

I have just built this and am facing an issue with loud pops and clicks on the output. I have a scope (which I fully admit I don't know how to properly use yet as evidenced by a phone picture when I'm sure it can capture!) which is showing random-ish but very regular - every couple of seconds - bursts of high frequency noise. I'm not sure if I should post the schematics as it's his work, but the attached pictures show the burst at the inverting input of a NE5534 RIAA / gain stage (yellow trace), and in the other picture the up closer and also showing the non inverting input, which is basically straight from the RCA.

I have tried turning off wifi / smart devices etc and that doesn't appear to change anything. Is this some kind of RF interference, or sporadic oscillation, if that is a thing that can happen? Any suggestions on where I should look next and things to try would be much appreciated!

Cheers

Hi All,

I noticed that in some branded speakers there is a "piggyback" magnat on the woofers (like in the attached photo) and I was wandering how this "piggyback" affects the woofer?
How it affect the woofer's T/S parameters? and is there any benefit in adding an extra magnet to a woofer which is part of a "branded" speaker?

Thanks

Hi all,
After seeing the measurements of the famous Topping PA5 amplifier, although I haven't seen an example yet, I thought, "I wonder if a class d composite amplifier can be made?" question stuck.
What do you think about it? Can an audiophile amplifier like the PA5 be designed with a nested feedback based on TI's PFFB TPA32xx structure and using low noise / distortion opamps?
I'm curious about your thoughts on this.

Hello ,,,Those days I’m trying to make a small solid state amp , and I found a nice orange amp crush 20L ,, but I will put another preamp section and I will keep only the power section from ORANGE … but I see strange things in the schematic . First strange thing it’s the voltage regulator where it goes to ground ( I spot with green mark ) .. the second it’s the FET ( spot with blue mark ) , the preamp section goes to the drain of FET , but why not go straight to the TDA2050 input ?
any answer could solve these strange things for me… thank you

Hey guys.

I just got a bunch, 30 pieces of so, of these really BIG capacitors, only because it was for sale at a very low price.

Now... Is there any use for such big caps in tube amps, or should I just try and resell them to buy other more useful parts?

Seems too big for tube amps for me. Most of what I see use 100 or 220uF high voltage caps, 470uF at most.

And just out of curiosity... What are those big 450v caps used for? Heavy industrial equipment, maybe? What else?

So... Should I just sell them for a burn price online, and buy me more tubes and transformers, or should I keep and use them on tube amps?

What you guys think?

Thanks on advance for any light on this subject!

Morning! I am getting close (relatively speaking) to finishing up a TD125 with the SG4/MA-3D electronics that Pyramid developed. Since the SG4/MA-3D replaces the original electronics I am not using the original transformer.

I had a custom face plate made to keep the original strobe functional, but it's not lighting the way I have it wired at 120v. It looks like it the strobe actually runs on 220v.

Is it possible to run the strobe on 120v? With a different resistor than the stock one? Any insights on what that circuit would look like would be very appreciated.

Being extra cautious as I don't want to risk damaging the strobe.

I can get the Dayton sooner but would rather and will wait and avoid it if the mini is a good deal better..
https://www.minidsp.com/products/minidsp-in-a-box/minidsp-2x4-hd
https://www.parts-express.com/Dayto...gnal-Processor-for-Home-and-Car-Audio-230-500

Hello, I’m after a wide-band driver that will play from 150hz through to 15khz, as that’s the limit of what I can hear, but the key for me is that it’s smooth or controlled through the sibilance range as I am super sensitive to harsh S’s to the point where I get a headache very quickly if it’s not controlled which ruins music listening for me.

The problem is I don’t have the luxury of being able to demo lots of different full range drivers till I find the ones that suit my taste.

Are there particular drivers or types to stay away from or are there any clues to look out for in the published frequency graphs?

These speakers will be used for relaxing too after a stressful day at work at moderate to low volume and, I love a good stereo image with low level details and to hear the ”texture” on strings and vocals etc if that makes any sense. I have a pair of massive klipsch chorus for when I want scale and to party😊

Thanks in advance

Matt

A very newbie question here. I've never kept up with multichannel audio trends. However, I do know that I can't stand 4th order lowpass filters on subwoofers. Is it possible to use a custom lowpass of, say for example, 98 Hz, 2nd order Bessel on an external DSP while having a full signal routed to it? How would I do this? Thank you.

Hi

I am having a rather unusual problem with this amp. When I first got this amp, there was power but no sound. Upon observation, I realised that non of the tubes were lit. I left it aside and a little while later I tried again. This time, all the tubes were lit and there was sound. I kept turning on the amp every now and then and the tubes were all litting up. The next day, when I turn on the amp, again, they were all dead. After sometime, I tried again and the tubes were litting up as usual. I kept doing this for a few days, and it was litting up at times and dead at times. Finally I took out the board and resoldered the whole board. R81(470K) was blown. I replaced it. After putting back everything, I turned on the amp and all the tubes were litting up and the amp works as usual. I having been turning the amp on and off for the past few days and the amp was working OK. I rebiased the amp and finally decided to put back the amp in the cabinet. After that I plugged in a signal and let it run for about 2 hrs and turned it off. After about 3hrs later, when I turned on the amp, there was no sound and all the tubes dead( not litting up). There are 3 wires from the transformer for the filament voltage going to the board. Blue(3.15V AC) going to WP5, Black(0V CT) going to WP7 and Brown(3.15V AC) going to WP8. I pulled out the blue and brown wires and measured app 6.7V ac across it , but when I plugged back the wires to the board, the tubes were not litting up. I realised that the blue wire(3.15V) was very hot and had turned slightly brown at the transformer side. What can be the problem, is it due to a problem on the board or the transformer itself or the tubes. Please assist.

Thanks

I had been using this OB 4way active with 2 of minidsp 2x4HD for each channel, but due to my stupid action updating umik-1 firmware while 2x4HD was also connecting to my pc then suddenly killed 2x4HD but lucky still have another board. too lazy to send it back to HK for repair, then i convert it into 2 way active with ribbon tweeter use simple 1 capacitor filter and only use 21" woofer which was crossed around 320Hz with harsch XO. you might recognize these woofer in SBAudience brand

21" woofer https://acrspeaker.com/product/21-pa-113212-sw-fabulous-by-acr/
12" woofer https://acrspeaker.com/product/12-pa-75124-w-n-fabulous-by-acr/

when I read Troels ATS-4 which apply overlap woofer and midbass without hpf seems interesting idea which i might use on my OB. so i just import each driver frd and zma from datasheet using FPGraphTracer and play with Xsim based on troels xo value as starting point. attached is the result

my idea is that i will use this overlap style where 12" woofer will not have hpf filter then using minidsp 2x4HD will be filtered around 320Hz and powered by aragon2004. my estimated 21" woofer LPF around 80-100Hz with impedance correction. because i'm not so good at passive xo design so i'll need anyone input for each value that i use especially for inductor because i have to order custom size.

attached in zip file with xsim frd & zma used

thanks for your valuable input

can somone send me a schematic diagram for the gemini xg-1100 amp ?

Hello.I am making a simple 0.5A /35V psu with a 24Volt AC transformer ,4 diodeS UF4002 and a 2200uF capacitor. I was considering the initial charge current and if the diodes are ok to handle it or should i move to something like HER205? Simulating with a 100 ohm load to get an idea of the current pulses in each diode i got the image below.So how i select a diode with respect to these simulation pulses?

UF4002 Datasheet says :
IFRM Repetitive peak forward current of 10A
IFSM Non-repetitive peak forward current of 30A

HER205 Datasheet says :
IFSM Non-repetitive peak forward current of 50A

Hello,

I have drafted schematics in the LTSpice of the six LM3886 that could be a really cool project to attempt. Attached are simulation files and LM3886 model. Importing the model basically requires to copy it all into your LTSpice internal directories and then edit all of the files to correct the path string.

Hi all,

I am working on a TPA3251 project for a while with some good components like;
Inductors, 7uH Würth 7443630700,
Main reservoir caps, United Chemicon's 2000uF/50v 25mohm x 4
After regulator electrolytic caps, all ultra low esr polymer
Signal line caps, all metallyzed polyproplene and polyester type (no ceramic caps on signal line)
Decoupling caps, Elna Silmic 2
Opamps, OPA1656
Linear reg, ultra low noise LT3045 etc...
Also, its possible to make PFFB configuration with THT components on bottom side with point to point tehcnique. (because its too hard to make it with SMD components).
NFB lines are appx 55mm for each channel which is some long.. But the circuit can work without PFFB.
Anyway,
TPA3251, LT3045 and LM5010 chips are still available on Aliexpress market.
So I think its worth to make a good amp.
What do you think about my schematic and PCB layout?
Any comment will be helpfull.
Thanks in advance.

Where this the files UCDs of http://www.classd.fromru.com?

Thanks to ALL.

So I have noticed when people are using smileys that some look unusually fuzzy, so I had a look at the code and to my surprise they are linked to an external source, how come, are they using mobile phone and have selected the smileys Android or iOS have preinstalled or somehow pick an external link?

Here's one smiley example and there are a few more just couple a posts above from the same thread I was linking this quote from.

🤣

Click to expand...

That smiley in the quote is linked to: https://cdn.jsdelivr.net/joypixels/assets/6.5/png/unicode/64/1f923.png
It appears to be so that externally linked smiley is 64x64 pixels and gets scaled down on this forum and in the process becomes fuzzy looking.

And here's the same smiley, 22x22 px, which I picked from the smiley collection held on this forum.
🤣

so the first thing with this is one of the power supplies has no fuse in it and there is a broken joint on the bottom of the fuse holder
well it wont be that as its the 115v supply

For Sale a textbook Bruno Putzey balanced preamp, fully assembled. The issues with linearity of the volume control and high gain have been tackled with a mechanical coaxial control with gross and fine regulation and with a mechanical limiter.

Price 150 euros or best offer. Shipped from Vienna (Austria)

Why does this matter to my ear.
I hear great highs from NC500's class-D as good as good linear amps when driving say a nice even benign flat 4 or 6ohm ribbon tweeter with low phase angles.
But when the same amp is driving a speaker with not such a benign load I change my mind from nice to so so about the sound, and linear amps then sound way better.

Cheers George

OK, looking to start a project soon - an open baffle set of speakers - Dual Eminence Alpha 15A with a Fostex FE108EZ...kinda modeled / designed around the Emerald Physics CS2 and Martin King's Open Baffle White Paper. Had a pair of EP CS2 a while back after reading they were like Quad ESL-63 on steroids...well not exactly, but I was still impressed on a few things anyway (their bass and "Lively-ness"), and decided to someday build my very own...with a little tweak on the HF driver. I picked the Fostex as a few here believe it to be a great driver for HF for an open baffle setup, and also recommended in Martin King's white paper...

I have four channels of Hypex UCD400, so all good on amplification. Preamp is 6922 based tubed Music Reference RM-5 (great Phono stage) and source is an AMR DP777SE DAC connected to a computer and a Pro-Ject RM9 Turntable.

So the question -

I can do the DCX2496 doing the Crossover at LR24db/oct @ 1000hz for both drivers with EQ tweaks here and there, (with settings like the EP CS2), OR a Passive Crossover at LR24 db/oct for both drivers at 1000hz and use the DEQ2496 "correction" in the digital domain for LF and HF....

I guess I could just use both Behringer units too, so another option...

I also have the DBX VENU360, but I have yet to open the box and learn how to use it (I know, I know...sigh...)

Any advice to what is preferred? I understand this is highly subjective, but thought to just ask anyway...

I'm posting this from another site that he posted. I find this pretty amazing as this is a hobby for him and something he's doing out of passion. Check it out below and his website and YouTube channel. He has great info! Also, if you want to send him speakers to measure, keep in mind that there's no cost to you.

-----------------------------------------------------------------------------------------

Well, after months of back and forth, looking at expenses and trying to predict the future, I finally did it...

I have acquired a Klippel Near Field Scanner!!!!


As some of you have seen me say before, it takes me 10+ hours; sometimes literal days. The NFS will cut that time down significantly and provide even higher accuracy data. I should be receiving it hopefully within a few weeks. I am awaiting a shipping date from Klippel but I just sent payment for shipping/import fees this morning.


It's going to take me a long time to pay this off... at my current YouTube revenue rate it may be 10-15 years (I have literally been averaging $10/day; which is nice but it is nowhere near enough to make a living from). So, it should be apparent (if it wasn't already apparent) this isn't about money for me but about passion. Frankly, if I were in this stuff for the money then I would just throw up subjective reviews like so many of the other reviewers and knock out a review per week. That's not a knock against those guys... plenty of people watch and appreciate that content. But that's not my goal with my channel/site. For me it is about gathering evidence (data) and using that to help draw meaningful conclusions about what we as listeners like and prefer and then use that knowledge along with future data to help inform in order to make purchase decisions that make more sense for us. I am trying hard to do my best to provide objective and subjective; that's my real goal. And I think I do a good job but the NFS will allow me to take it to a new level. This isn't my full time job but I work just as hard at it as I do my day job.


As I've said before... if I can just break even, this is a great way for me to pass the time in a meaningful way. I get to play with cool toys. I get to make more friends. I get to learn. I get to grow. And, maybe, if this passion doesn't wane (it hasn't in my last 15 years) then it'll be a hobby for me after I retire from my real job. And the community benefits with great data. The data can never replace hearing something yourself (because tastes can change, etc). But I am a proponent of good data to help us build a better understanding and filter out the junk from the "maybe" pile.



Now, I'm all in on this and payment is being taken care of on my end. However, I have started a PayPal contribution page for those of you who have the means and have found my efforts useful enough to warrant contributing to the cause in order to help me at least offset some of my costs. I know times are tough for everyone so if you can't or simply don't want to contribute, hey, I get it. Like I said, it's already a done deal. But if you are able to help just know that I am extremely grateful for anything you can help with.

Erin's Audio Corner
Erin's Audio Corner - YouTube


If you want to help contribute to the cause the link is below:
Contribute to Erin's Audio Corner Klippel NFS Fund

Full disclosure: Erin did come on my podcast and that episode is coming soon so please subscribe to my YouTube channel! 😉
The Intellectual People Podcast - YouTube

I am attempting to repair the volume control on a damaged Rega Mira 2000 integrated amp that I recently required. The volume control is a 20 step mechanical rotary encoder with a built-in button that switches to input selection when the shaft/button is pressed (original was bent and damaged). The encoder controls a motorized pot within the amp. Thinking that rotary encoders are standard parts, I ordered a 20 step Bourns encoder with the same dimensions as I couldn't find the original Alps unit. It works fine, however the direction is reversed when turning the encoder; turning it clockwise decrease the volume and the same with source selection. My initial thought is to cut and reverse the traces to the pins on the encoder, but if there is a more elegant solution or maybe a different part that I'm not aware of please let me know. I've attached the schematic I have of the main PCB, the encoder is on a daughter board not shown that connects via the SK3 connector shown in the schematic, this is the encoder that I am using as a replacement.

Hello,

Anyone have a stash of NOS or working used vintage audio transformers they ware willing to find a new home for?

Seeking 2 each of the following hopefully at a reasonable cost:

1. Triad HS-56 transformer
2. Triad HS-26 transformer
3. Peerless S-217-D transformer

Shipping to San Francisco CA.

Thanks in advance!

Greg

High Fidelity Performance Op-Amp.

No need to make too complicated
when such good results with fairly simple 3 stage circuit

Set up this amplifier design model
in your simulator
and you will see!
🙂 And why not layout your own Hifi Op-Amp PCB
and make a few small killer OPamp devices of your own.

Version 1 of mine used 17mA current total
at +/-15 Volt DC
and tested for practically 0% THD distortion, in various loads and output voltages.
Fourier Analyse shows very nice even spectrum of harmonics.


Regards
Lineup Audio Lab Productions

I just want a decent make - Sony / Kenwood no bells and whistles like apple carplay or GPS, but touch screen and Bluetooth, head unit availed in UK please 🙂

My midrange stopped working, I suspect it might be the resistor. Does anyone know how to check / replace the resistor?

This is the resistor I am referring to (mid-range): http://parts.wilsonaudio.com/resistors-for-the-watt-puppy-series-7/

¿Qué pasa amigos? ¿Hay un equivalente para los fets fb3307z? Son de un amplificador kicker dx1000.1. No los encuentro en mi ciudad y quisiera saber si existe un equivalente. greetings friends

I have for sale paper in oil tin foil 6 pieces of 0.1uf and 4 pieces of 0.47uf this truly verry good sounding caps. This are new old stock. Never used and new. They are no longer in produktion. Verry natural sounding caps. Price for 0.1uf is 20 eu for a piece and 30 eu for one piece of 0.47uf plus shipping inside EU. I accept paypal.

Hello,

This will be my first speaker build. Would like to try out a full range bookshelf as I don’t have the space for towers. I don’t mind adding a small subwoofer down the line if needed. Is the maop 11 a good choice?

I would be interested in good mids and highs if possible.
Thanks.

Bought from Future Electronics several years ago -- IXTH50N20 (obsolete) N-Channel +200V, TO-247 gfs=32 Siemens. IXTH24P20 -200V, 15 Siemens TO-247. 5 pieces of each, $10 takes the lot (10 pieces) Shipping included to continental US via First Class Mail.

Hello!

Why are those tubes so expensive? This seems to be over the top....

Hi,

I would like to build one of the First Watt DIY amplifiers to power my Ron Clarke Austin 126 Rear Loaded Horn speakers. The speakers are using the Fostex Fe126en drivers.

Please could someone point me in the direction of which of the First Watt offerings would be most suitable?

Thanks in advance for any help.

Hi all. Being sold by the pair, the famous (ha) open baffle woofer.

Driver info page here.

• $150 per pair, plus shipping (from NY).
• Buy three pair for $400 (six woofers @ $66 ea.).

New in box. This is leftover from a larger order, which I didn't end up using.

I'll be posting several threads here in the upcoming week, selling such leftovers.

I've made many sales here the past couple years. You can see my work here: www.aforara.com

Thank you for lookin' and have a lovely day.

Since many of you on here build your own DACs, I thought you might be able to give me a clue to what's wrong with mine. It's an older Musical Fidelity A3.24, which was one model down from their flagship when it was made. For several years, it sometimes makes a loud 'pop' when I insert a new CD into the transport. It does this with different transports, but it's currently hooked to a Pioneer Elite DVD player.

When it does this, the "Locked" LED on the front panel blinks. But it doesn't do it every time a new CD goes in. I haven't been able to discern any pattern to it. I've just gotten into the habit of muting my preamp every time I change CDs.

Are DACs supposed to mute any un-musical signals related to getting a digital signal lock?

anyone familiar with this amp? Schematics? Cannot find any model number.


Thanks.

I would like to create a list of speakers fit a 2nd generation Tundra, NON JBL no navigation.

Did you install one which you are happy with? Did it fit right into the door? Please, help us who want to upgrade the speakers.