(UPDATE pricing & quantities 4th feb 2019)


Limited quantities of the following: new, unused, and guaranteed ICEPOWER modules:

50ASX2 SE version = 80$ CAD (+/- 62$ USD or 54 EUR) (qty available: 16)

125ASX2 = 135$ CAD (+/- 105$ USD or 90 EUR) (qty available: 13)

700ASC2 = 450$ CAD (+/- 370$ USD or 320 EUR) (qty available: 2)

1200AS (cables included on that one only) = 480$ CAD (+/- 420$ USD or 365 EUR) (qty available: 1)


300AC = 55$ CAD (+/- 43$ USD or 37 EUR) (qty available: 8)



.::: any order of 500$CAD or more will have 10% discount :::.

.::: any order of 1000$CAD or more will have 15% discount :::.

.::: any order of 3000$CAD or more will have 25% discount :::.





NOTES:

.: Pricing is per module and do not include any cable or chassis or technical support, just the module (except the 1200AS).

.: To be paid in CAD (Canadian dollars) only, either by Paypal or bank wire transfer.

.: Actual shipping fees will be charged (must be shipped with tracking number) and is roughly 25-40$ CAD for continental U.S. per package (can include many modules) and minimum 45$ CAD for anything overseas, including all Europe, Asia and Australia.

.: Canadian buyers will be charged taxes based on their province (contact me for info)

Thank you!
Jon

Hello!

I have a 4 Ohm 12" subwoofer with 200 RMS, 40 Peak ( Rockford Fosgate P212S4 Punch Stage 2 12" 4-ohm subwoofer at Crutchfield )

from years ago and built a beautiful box for my first car out of it. Now I will be home over the holidays and would like to take it out of the attic and put it to use in our home stereo.

So far I have figured out I would be fine as long as I use an amp that can handle 4 ohms. This one even has a crossover built in ( Lepai 2.1 2x40W Amplifier LP-168HA without Power Supply )... so it seems like a good solution. Is the power going to be enough? I'd rather have an amp that can match the 200 RMS of my sub... any suggestions?

Second question is how I connect to my stereo. I could use some line level converters as I did when I had this in the car, but I think it is possible to use the TAPE OUT ? It is an old Panasonic amp from the 70s.

Thank you for the guidance. I'll be home for a month including quarantine and want to make the most of it.

Rotel RX-950-AX wont power on. In standby only

Hello and Happy Thanksgiving
My Partners Rotel won't power on

My business partner and I have been giving each other birthday gifts for 30 years. Needless to say I was running low on ideas. I asked him if he had any wishes and he asked me if I could take a look at his Rotel Rx-950-AX receiver because it had a broken "power on button". To make a long story short after searching the net for two weeks I finally found a DPDT switch that would fit the circuit board and I installed it for him. (it had lost its latching ability). Voila replaceing the switch is was not the problem. It remains in standy.
So far I removed two capacitors located near the transformer c955 and V956.
I have not replaced them yet. I have identified the diode recitifier and some other capacitors of interest 902,903, 905,907. I tested the 902 and 903 with an ESR meter and I believe those caps are good. I can not test 905 or 7 without doing a tremendous about of work removing the board. I was wondering if anyone could give me some testing ideas that might help me isolate the problem better. I hve not tested the diode recitifier yet.
Thank you
I can provide pictures if needed.
Also tried to upload service manual from another site but "size to big"

Thanks Bill

Hello, I have a Technics sa 202 receiver that is quite when I switch to stereo. Strong signal and music in mono but all quiet instereo with the meter dropping a couple of lights? Any ideas...thanks

The headphones are AKG 240mkII. 55ohm, 200mW.

Q1. I’ve read that a multiplier is good, is 10x but 2W seems too high?

Q2. Reduction of impedance, using push pull and multiple devices, 110mA max each in an OTL push pull class AB1 configuration.
If I use 4 devices that’s 1/32 = 4* 1/R therefore each tube is 1/4 so 8ohm.

Then using Negative feedback to get from 8 to 4ohms.

Calculate 2W 32ohms sqr(2/32)= 250mA, 32*.25 = 8V peak.
sqr(2/4)= 707mA, 4*.707= 2.829V peak.

Gain 8V/447mV = 17.8971x

But if the impedance dropped to Vout/Vin, or more accurately iirc G/(G+bG) so the gain we actually have into 4ohms is 8/2.829 = x2.82, so we have a ratio we can use to work out the gain we actually need with the NFB in place to be?

I’ve been staring at numbers too much and crap sleep but I think I’m onto the right track?

As per title need help with this turntable...
Does someone know where I can get a power transformer for this record player or have one willing to sell ?
47nf (X2) capacitor shorted and passed 240V to the 110V line and fried it.
Dual P/N 244474 (position 111 in service manual)
0-110-220 - 16.5Vac.

Offering 5 cleaned and tested 6SN7GT/A tubes. All test good on a TV-10D/U military tester. No shorts and all pass tests for gas & leakage. Test results on tubes (minimum conductance for both triode sections = 1650) as shown in photo from left to right:

Tall Tubes (6SN7GT):
Sylvania #1: T1 = 2500, T2 = 2300.
Sylvania #2: T1 = 2100, T2 = 2650.

Shorter tubes (6SN7GTA):
Sylvania: T1 = 2300, T2 = 2100 (tube type number on this one is worn but readable).
GE: T1 = 2600, T2 = 2500.
RCA: T1 = 2500, T2 = 2450.

$40 for all + $6 for First Class USA shipping. Tubes will be individually boxed. Payment via PayPal.

First of all, let me introduce myself, I realize this might not be the correct place to do so, but anyway.

I started after rave reviews tinkering with these modules, I got my hands on one, and it sounded stunning, so I bought a second one t run them in BTL on my system.

Long story short, no pun intended😀, I managed to short out the auxiliary power on both of them, I read all possible threads about these modules in this forum, so I know by now where F300 resides, but it is not clear to me where to acquire a replacement fuse, or alternative for it, has anyone any suggestions?

Working on a RF type X2 with DSP board. Sometimes the amp won't "unmute", but all voltages are there, display is ok, but cannot activate any button at the dsp keyboard. When pulsing the remote (about 10x...?) the amp is working ok.

It is like an other thread i think: https://www.diyaudio.com/forums/car-audio/206160-rockford-type-rf-x2.html was there any solution provided for that problem?

I see at the SG3525 a sync-in signal coming form the DSP board. Only a diagram available for the amplifier /power supply part, not the dsp board...

Maybe some leaky smd capacitors on the DSP board..?

Is it posible to make a filter, working off the volume control, which lowers the volume of frequencies below about 55Hz as the volume is turned up. This would allow me to use open baffles with boost on the low frequencies for quieter listening without using subs but If I listened at loud volumes I would turn on the subs and the boost on the open baffles would be reduced. I guess I am looking for a circuit to reduce boost with increasing volume but operated off the volume control so that two separate controls are not needed. This is to reduce xmax at high volumes. Thanks for any help, negative or positive.
jamikl

I am planning to build this amplifier. I would be more than happy if someone could take a peak and give constructive advice or/and correction to this build. This is ver. 1, so in the near future I am planning to update it after I do some measurments and listening tests.


Any suggestions are welcome.

Hi guys,
An acquaintance of mine is currently recapping my Plinius preamp and we've ran into problems sourcing the 4 main PSU caps.
The info I got from him was: P 16mm, H35mm max, D32mm. 4700uF/63V

I've only found one picture on A'gon but can't make out what caps are these, I suspect Rubycons:
https://ucarecdn.audiogon.com/94c1e...scale_crop/840x630/center/-/quality/lightest/

I haven't seen a cap with 15-16mm lead spacing in this capacity and all are snap-ins. Any ideas? 😕 I don't think the original caps were custom made The preamp has been recapped before but I don't like the way they mounted the new caps - horizontally, zip tied and with wires going to the PCB.

Working on an EL 84pp amp and I have a question about the power supply. The Heater Elevation from the 6,3v windings for my ECC81 tubes. I made a terrible drawing, but I hope You understand. Is it ok to connect the elevation like this?

I don't know the correct term, I know it as a 'Stanley' knife with changeable blades. Perhaps 'utility' knife is the universal term.
I surely cannot be the only person who's thumb invariably hovers over the blade retract button when cutting?
Any recommendation for a knife that I won't continually retract the blade while trying to cut?

I currently have the Dayton 8" reference sub in their sealed enclosure and am thinking of adding a second sub. I really like the sound of the dayton and even with just a 100 watt amp it goes plenty loud for my music listening levels.
I don't have enough room to add a second of the same and I've read that it isn't good to mix sealed and vented subs. Is there a problem mixing different sealed subs? I was looking at either LS10-44, or W8-2282 in a small sealed enclosure.

I traced the PS of my tt and it looks like the attached. As I know close to nothing about motors 🙂 could you please help me understand
- what is the purpose of the third cable (red) going to the motor
- is there any circuit to build for controlling the rpm?

thanks in advance

Dear members,
I need to find a copy of the magazine L'Audiophile" issue 39 (Autumn 86)
If anyone has it or can make a scan/copy of it please contact me at skylimit000@gmail.com
Thank you

From Altec's famed 'Hollywood' era, here is a wonderful example of a very rare and sought-after tube output transformer from the late 1940's. Used in various Altec power amplifiers with push-pull output stages comprised of a pair of 6L6's or 807's.

Original published specifications:
Altec TL-217B Output Transformer (Same as TL-217A, except with 12" long leads)
Max Operating Level: +35dB / 19W (ref 6mW)
Frequency Response: FLAT within 1dB from 20Hz-20kHz!
6.6 kOhm center-tapped primary, Max primary current 65mA, current unbalance should not exceed 7mA
10 & 20 ohm secondary taps
3 ½” x 3 5/8” x 4 1/8” (approximately 8.9cm x 9.2cm x 10.5cm)
Approximately 6 lbs / 2.75kG

This item was purchased at the estate sale of a locally renown amplifier technician and Altec fanatic in his 90's. His license plate read "ALTEC' for over 30 years. He was a certified Altec tech going back to the 1950's, and had quite a bit of Hollywood-era equipment, including a pair of Altec A-324 amplifiers. This transformer was purchased in a plastic bag marked "TL217B - 324 Spare" and matches resistance measurements of other TL-217 transformers. That information, along with the matching dimensions, weight, and number of primary and secondary windings gives me very very high confidence in the origin and model of this vintage transformer.

Resistance measurements made with a Fluke 115 multi-meter. Resistances are consistent with measurements made of two other fully functional TL-217 transformers.

Primary
Black to Brown: 264 Ohms
Brown to Brown: 133 Ohms
Brown to Black: 132 Ohms

Secondary
Black to Yellow: 1 Ohms
Black to Grey: 1.1 Ohms
Grey to Yellow: .6 Ohms

From any primary wire to any secondary wire, resistance measures over 1megOhm, showing insulation no shorts between primary and secondary windings.

Guaranteed as-described. PM me if interested.

I recently bought some cheap Chinese prototyping pcbs from eBay and thought I should pass on a little warning. They smell like the old Radio Shack boards while soldering but a few hours later I tried going to bed but found my nose completely clogged. It was so bad I woke myself up coughing. The next day my nose was still clogged but a decongestant cleared it up. I've been soldering for over 30 years and never had any reaction like that before. The remaining boards went right into the trash. Here is what they look like.

I have a pair of Honey Badger boards that I put together. I used it for a few weeks before eventually having a thermal runaway problem. I was told that it simply was not possible with this design and I'm not able to troubleshoot it myself.

Nothing smoked but it got quite hot before I shut it off. I don't know if any parts got damaged.

Whoever buys it needs to be able to troubleshoot. I haven't tried to use it since having a problem.

I will also include 12 Panasonic 8200uF caps, and a DIY Audio soft start and DC protection circuit. This was all bought new in 2014.

$170 US shipping included anywhere in North America. Everything is sold as-is.

Good morning
I am an owner of an Accuphase C290 pre-amplifier. I would like information about the electronic compatibility / impedance with the X250.5 amp, or your advice on an alternative coupling

Hi
SOLD a pair of Radian 475 drivers with Beryllium Diaphragm .
i bought these to be used in a project that never manifested , time to make some space .
these drivers are brand new , just some handling .

asking $900 ,

i cover shipping at my asking price , you cover paypal .

i also have a pair of seos 18 horns in black i could sell with them .

Hi there,

Has anyone got a service manual for a Brue & Kjaer Sound Level Meter?

Cheers

Alex

With the extra time at home, I'm working on a pair of bwaslo's cosyne speakers.
I'm following the "cosyne" design literally.

My goal was to have a fun carpentry challenge that results in great sounding speakers. I was planning to make some horn speakers and then these synergy designs started popping up in my searches! WAF will be an issue eventually but I decided to go ahead even if it means these stay in the workshop.

Step 1 is to build the horns without a cabinet but ultimately, I want to have a full range setup with these. Either with full range enclosures or in combo with a tapped horn bass/sub.

I'll post pictures of the build - I have done a fair bit of challenging carpentry in the past so designs like this are fun to ponder and work out on the table saw.

I started out collecting information. it took a while to discover Bill's site...
Liberty Instruments Home Page
and also took time to discover that many of my questions from reading the pdf were answered in the accompanying spreadsheet.

I don't have experience with hornresp or any other modeling software. It looks like a fun rabbit hole but I have other rabbit holes I'm already in that I need to stay focused on.

I tracked down the "bulk buy" drivers easily enough, or so I thought.
P-E has the Gento ($1.25/ea in bulk!) So I bought 9 of them.
I then found the Aura Sound drivers on Ebay for cheap but after they shipped, I realized these were the 4 ohm versions.

Luckily, I found a "kit" of the Cosyne drivers here in the swapmeet section. So I'll end up with extra Gento drivers and an extra set of 4 ohm Aura woofers to either return or use elsewhere.

looking for a scheme - please give

kuly-s@rambler.ru

VENDETTA　RESEARCH　SCP-2A

tell me what transistors are their name

I found one on the Internet - but it does not fit - it is different in the photo there is a second chip in this circuit there is no chip

Hey guys,


I want to build a tl line and first tough of building a Thor Speaker but reading about the Ariels changed my mind.
The problem with ariel is that,as most of you know, the Vifa drivers are no longer available.
I've been reading online for replacements and found the following 3 drivers :

1. SB Acoustics SBMFC30-8
SB Acoustics SB15MFC30-8 5" Poly Cone Woofer

2.Peerless NE149W-08
Peerless by Tymphany NE149W-08 5-1/4" Fiber Cone Woofer Speaker 8 Ohm

3.Seas ER15RLY
SEAS Prestige ER15RLY (H1455) 5.5" Reed Paper Cone Woofer

I have no idea which one actually sounds better. That's why i need your expertise. Which one would you go for?

I've been having a lurk around and decided to dive in. Mostly I like to play with ham radio (KL5A) and have a couple old Heathkits waiting for some restoration, but now that I have a grandson who is tech oriented I thought it might be fun to build some DIY electronics and see if I can get that squiirel running in his head. Right now I'm thinking I'd like to find a simple hollow state amp suitable for breadboarding that was can build together, like the ones I dabbled in as a young teen and mostly didn't electrocute myself with.
Cheers from NoMi!

Hi Guys,

I've been reading information on Aleph amplifiers for months and I would like to build an aleph 5 because it has some characteristics in its design that I consider quite important for a good amplifier such as: class a, single ended, few stages, use of mosfets.

But a person who should help me to build my aleph told me that alephs are not single ended amplifiers because there is no capacitor at the output.

Could you help me to demonstrate that aleph 5 design is a single ended topology? And why hasn't it got a capacitor at the output?

Thank you

Madisound's got some new photos up: SB Acoustics SB65WBAC25-4 2.5" full range

Have to say, it's kind of ugly... also, the label says SB65WBAC25-4-WP, not sure that "-WP" was there before.

I am curious if anyone has replaced the comax switches in a JL Audio 500/1 v2 or any other JL Slash Amp and has the specific part number for the 3-position slide switch? The 3 position switch used in the Amp Low-pass filter has slide contact issues and probably needs to be replaced.

Hello,
please find attached A200 schematic.

Musical Fidelity A200 - Audiomaniacy

I own Musical Fidelily A120 which has more or less same schamatic as A200.

As you may know Class A is limited to a few watts beyond which (A1, A100, A120) switch to class AB.

Which component should I have to change and trim to SAFELY increase the bias for a wider class A range?

Actually is shown 300mV on 0.47 ohm, that is 0.64A only!
Definetively not a 40+40W Class A as declared.

Hello, friends!

Can you give a hint on these question?
- Do I need a volume control on the AMP? My father tells me that I do not need it on the amp because I plan to use the external audio card of the PC as the sound source, and it has it's own volume control. This is in fact true.
Will the volume control somehow deteriorate sound quality? I am looking at potentiometers of ALPS, TKD, Elma. Can you recomment any?
- I would like to have an audio level meter for both channels on the amp. I think they look nice. Something like Audio Level VU Meter WF1029X. Do they work fine in the amp? any particular model you can recommend bellow 50 EUR?

Thank you!

I have a Cambridge Audio Trac 1 CD and a DAC 3 digital converter. I want to improve but I don't have an electronic schematic. I was looking everywhere in Poland in Stereophile, Stereonet including the producer in GB said they do not have in my opinion. Maybe someone has or knows where to down

Good morning everyone, in the ambitious and maybe even silly attempt to extract blood from turnips ... I need some advice.
It happened in my hands dumped by a friend who buys cheap things and then throws them away (me 😱) a little preamp working with 12VDC with an internal a step-up dc dc converter to generate the anodes voltages.
The original tubes are Chinese 6N3s.
It works 😱 but I have some doubts about the sound quality 🙄
Looking inside I saw that it has a high voltage of only 100VDC I think the anodic one ... in absolute terms very low compared to the usual and recommended 200-250VDC.
Through another friend I learned of the existence of converter sockets with bottom 6N3 and different tops that allow the use of a very huge variety of double triodes such as those of the 6922 family or of the 12au7/12bh7 family.
The question is ... is there a tube that works particularly well even when supplied with voltages this low ?
I would be willing to try it without much pretense with its relative socket converter. For example ... at low voltages a 12bh7 may be a better choice than a 6N3 or would the differences in sound be minimal in the end?
Let's say that these devices have introduced me to the sound of the tubes that I am starting to rather like, even if only for a hybrid system with a solid state power amp.
In general, this preamp already makes the sound more relaxed, fluid but with a good overall transparency. It is a little lacking in the highs and above all in drive ... in the sense that if i put a Toto track with a lot of drumming the drums do not come out from the speakers like i would. Probably it is a matter of not so low Zout ? i do not know. I have not been able to recover the schematic unfortunately. But i am willing to try in the next days.
Surely it is not used at its best as a working point ...
in perspective next year I intend to devote myself with more commitment to a valve pre-line solution that can be quite definitive. For some weeks at least 😀
Thanks to all and again have a nice day,
gino

Yesterday i tested a fake tda2050 ic into heavy load(4ohm) and with absolute maximum supply voltage(+/-25vDC). During bass transients it mutes itself for 1sec or so(repeatedly). I never thought that this counterfeit IC has such a good thermal protection circuitry inside! wow! 😱 😱 😱

Edit:-maybe it was SOA protection circuitry, i don't know.

Looking for one Philips TDA1541A R1 or S1 Holland made DAC chip. If you have one for sale or not using please let me know. 🙂

Hello community,


because i have a lot of time these days, i started to build my new PA.
Because it is fully horn loaded, i need a midtop playing from 200hz, i was looking for plans the last days but i couldnt find anything... Is anyone here knowing some Horntops? Most likely i would use 10" and 1,4", the 18sound 10m600 is looking great for me.



I found DDS Horns, Design Direct Sound, DDS, fiberglass horns, horn lenses, fiberglass lenses, line array, waveguide, waveguides, asymetric, community, tweeter horns, mid-range, speaker lenses, speaker horns but there are few information on the website and i have no idea if they send to Germany. Anyone maybe having experience with them?

Would it be possible for a beginner to calculate such a horn on its own? What program should i use then?



Thanks alot for help

Dear Anyone.

Mods, feel free to move this, I'm a noob, didn't know where to put it (anatomical suggestions will be considered....!)

I've got Windows XP 64 bit. I used that because I've got 32-bit XP software I love using that HATES Windows 7 Emulation mode, it just smiles at you and crashes in that! Thing IS - I can't get my High Definition Audio Codec working.

Now on my old Windows hard drive it comes up as IDT High Definition Audio Codec, but it got automatically installed when I bought the computer and I don't have an installation disc, it would've been 32-bit anyway. On my Windows 7 disc, which the software hates, it says it's using Realtek. On my Windows XP 64 bit disc (3 separate discs, I just take 'em out of the tower and put 'em in again!) there's just an exclamation mark by it. I've tried no end of downloaded driver installation packages, mainly by Realtek cos I can't find many IDT ones to try, and it just tells me it can't find any hardware, or the hardware isn't working. I know the hardware's fine because it works like a dream on my Windows 7 drive, which I'm using right now!

At one point I had an installer that said I had to have at LEAST SP 1 installed on my XP 64 bit drive. So I found SP2 (remember the 'at least!) and installed that, tried to instally the High Definition Audio Codec again and it STILL said I had to have SP1 at least installed - it wasn't picking up that I'd just installed SP2. Yes, I'd restarted the computer.

That left me absolutely out of ideas. I've got a Foxconn 2ADA mobo with a sandybridge processor, if that helps anyone, and 6gig. of RAM, which was the main reason for 64 bit XP, so I could use it all.

If anyone's got any ideas how I could get noise out of my 64-bit XP drive, they'd have my eternal gratitude. Right now, I'm a disabled composer who can't compose - which, according to those who listen to my stuff, might well be a bonus but sure is frustrating to me personally!

Re. the SP1 thing - I couldn't find a copy of SP1, just SP2. Would SP1 have stuff in it that's missing from SP2, would that be the reason the installation software didn't recognise it? I've zero idea on that front, just vaguely guessing. Last question on the above.

The mobo's PCIe slots for soundcards. Would ANY PCIe soundcard be OK, or are there differences between 32-64 bit soundcards? I've tried googling 'Soundcards that work with XP 64-bit' and only get a short list of cards costing several hundreds of pounds (OUCH!!). But I've seen much more reasonably priced PCIe cards (like, £30) but have no idea if they'd work with 64 bit or not and the vendors don't seem too sure either.

Sorry for all the questions, just stumped.

Yours hopefully

Chris.

Hi, need some advice of 4 large caps in the PSU.
I need replacement but not sure which part to get.
The 4 big caps (32000uF 50V surge -10+75%) are aluminium electrolyte's (I Guess) and are located just behind the transformer Output, see schema :
PSU schema | martijnveulemans | Flickr

here another photo :
PSU Caps Harrison | martijnveulemans | Flickr

Can I replace them with this one :
Blocked

Thanks!

mini audio mixer 3chanal+echo pt2399+mp3 reader

Hello friends,

I need your expert help and guidance to point me in the right direction. I need a super low noise and fast transient response +/- 18V power supply for my phono preamp, but I am having a hard time finding any. I would be happy to buy it or build one from a kit (or at least a circuit board), but I don't have the expertise to design it myself (not from scratch anyway). Could someone please point me to a product or project or something to start from?

Input: 120V 60Hz
Output: +/- 18V (about 0.3A)
Speed and ultra-low output impedance over a broad bandwidth (ideally 3mOhm up to 100KHz)

I would appreciate any help. Thank you!

Hi all, I just ordered three boards each for the sinewave generator, the encoder, and the board to drive the brushless dc motors from Anaheim Automation. If anyone needs a set, PM me and I'd be happy to divide what I paid by three and sell them to you.

I obtained a free Simpson AC VTVM a few years ago. As I recall, it was completely dead - no light or anything. Tube complement is 2 12AT7s and a 6C4. On examination, it seems its only problem was the selenium half-wave rectifier went open. I replaced that with a 1N4007. The 6C4 also does not light up, but I will sub another tube to check that. Possible the 6C4 does not show a lot of glow - the 12AT7s glow fine.

Assuming it works now, how do I test it? Then if it works, how to calibrate? There's no adjustment to speak of other than the meter adjust screw on the front of the meter.

Hello, can someone identify these parts in a Kicker KXA400.4? They look like inductors but I don't know for sure, and I don't know the value. I haven't gotten the amp yet but I would like to add some of these to an order I will be placing tomorrow. Also, if anyone can tell me what this amp uses for PS FETs and output transistors along with any know commonly replaced parts for this model. Thanks.

Does anyone out there know the quiescent current and bias (dc offset) settings for my Sugden P128's, I am doing a full re-cap on them due to age and would like to set them up just right 🙂

Please Please Help Me !!!

Kind Regards Danny

Hello,
I have a pair of visaton FRS8 8 ohm, i need a home/enclosure for and I am having problems even getting going on the project as online enclosure calculators i have tried have issues with is specked Qts of 1.04.

All i am looking to make is a pair of small desktop/pc speakers; can someone help me with a bit of a design help please?

Even just the unported volume or ported volume plus dia/length, would be a major help. The rest i think i could figure for myself 🙂

Many thanks in advance imk

I’ve been playing with a Vifa TG9 supported by a pair of 8 ohm SB13PFCs for the last few weeks.
First: pushing it...
My initial thought was that the SBs, being a budget speaker, could do with the distortion reduction that push-push affords, so knocked up a couple of 20L test boxes, the woofers coupled together with a piece of pine with a thin strip of neoprene on the ends.
The initial xover was simple, a 33uF cap on the TC9, and a .68mH inductor for the SBs.
The sound was a bit wooly in the upper mids, so the next step was to add another .68 inductor in series with the rear woofer, which makes it a 2.5 way. Much clearer sound, and I omitted the pine coupler – too fiddly to get it in, didn’t seem to make any difference, but I don’t listen at high volume. Somewhere, I have an RTA sweep which shows two dips in the Freq. Response, the usual floor bounce dip, as well as a second from the reflected sound of the rear woofer, but it didn’t seem that noticable. Can’t bother dragging that computer out to retrieve it.

4 DC Sensors Mirand Audio like installed but naver used USD30 each (EURO 70 each new)

Can the HBR resistor 15ohms be added to the circuit to help deal with cross channel ground loop?

Hi,
A few years ago I bought a "Concertone 200" on german ebay. It was listed as rare but not working but I liked the look of it and wanted to refurbish it. I blindly disassembled it and then I moved to another town and didnt see it until today. I searched the internet for infos and the only thing I can find is a french thread and a german site called radiomuseum but theres alomst no info at all about this am. I know its from 1986 and was quite expensive back in the day. I would love to make it work again but I'm afraight it will be very hard or even impossible for me without a service manual or someone who knows this amp. So if anyone has infos on this I'd be very happy!!
Thank you!

If anyone, please contact me.

Thank you!

For Sale: AYA DS DAC Board more SMD chips

Last summer I purchased from Audial four AYA DS boards, with SMD chips soldered by Mr. Pedja himself.

Recently realised that I only need 3 of them, so, if anyone needs one board I will let it go for what paid: 80 euros (more Paypal and shipping freight).

Thank you!

For Sale: AYA II DS DAC Board populated with smd A/D chips.

I have 4 of them, purchased from last batch, and I only need 2.

Ask what I have paid: 80 euros for each + shipping cost.

Thank you!

Working on a Hertz HDP4 amp. It uses the IRS2092S driver ICs and IRFI4019H outputs. The outputs are dual mosfets and they use two in parallel on the output of the driver chip. Hope someone can answer a question on this design. I had two shorted outputs. I pulled them and powered the amp to test the driver chip. To see if I needed to replace it. when I powered it, the IC popped. Retested and had two more shorted outputs. I pulled all the outputs to test. When I powered the amp it popped the other three driver ICs. Is this normal for this design. I would think you can pull the outputs without the driver ICs burning up. Can anyone offer any insite on this? I can post pics of amp if you need them.

hi all,
the above says it all, this one has strange fault cuts out the in again? after 10 mins
regards
bob

Just a quick question regarding the loss in signal amplitude from gate to source in JFETs.
The output impedance out of a JFET follower is 1/Gm is it not? (Or is it 'Yfs' in JFETs and not 'Gm'?) What is the difference in 'forward transfer admittance (Yfs)' and transconductance (Gm)?

I have a buffer ckt using a JFET as follower, and in the bottom (JFET source) there is a CCS made up of another JFET, a 2SK3557 biased at ca 1mA. The load is a 10kohm resistor (the next stage opamp).

Using a CCS for biasing, there should be very little loss in amplitude, when the load the JFET buffer is driving is relatively high in impedance.

I have tested this using BF862, 2SK932, and 2SK3557. The BF862 and 2SK932-22 have no loss, the 2SK3557 has ca -0.3dB loss.
The 2SK932 come in sorted by IDSS in 3 grades, where the -22 has the lowest IDSS and the -24 has the highest. The -22 has no loss like the BF862, but the -23 and -24 have little under 0.2dB loss.

I assumed the highest IDSS version would have the best, or strongest, drive, and give the least amount of loss, but it is the other way, the lowest IDSS version gives the least loss. Is this always the case? Should I select low IDSS JFETs for source follower duties?

I included some distortion measurements and the 2SK3557 is not very linear as a follower, at least at this low current. The BF862 has slightly better figures than teh reference input signal, probably because it's linearity is slightly opposite the testsignal or something. Or it is just so low that the scope cant measure accurately.

I am a little surprised the JFETs loss when used with a CCS and driving 10kohm.

Anyways, I just thought this slightly interesting and perhaps some one else is experimenting with these JFETs.

As the title says, looking for a motel MDT 39 if anyone has one laying around in a parts box, I seem to have acquired one with a pair of mdm55's..

Funds are tight and they seem discontinued so I thought asking on here may help.

Thanks all.

I have an old Topward DC power supply that has some broken binding posts.

I'm looking for help sourcing a suitable replacement.

The shaft is 10-32 and approx 1-9/16" long. It need to be this long as it passes through two PCBs that are spaced 1/4" apart. 1-7/16" is the minimum length that would work.

Thanks.

Hey all,

I want to design some crossovers for my DMLs. I am currently using a custom 4 channel amp with active crossovers (limited to HP/LP at 50-300Hz though) for panel testing and room measurements but I want to eventually build passive crossovers for 2 way DML systems, or 3 way FAST/WAW systems using DMLs for top end and an OB sub. I just finished the Udemy online course on crossover design and they have you use DATS to do an impedance graph and then make a ZMA file to load into XSIM with your far field measurements from REW, and then design your crossovers from there. However, Exciters don't exactly compute in DATS like a cone speaker because you only have Re, Le and Fs from the manufacturer. You don't have any of the Q measurements, Vas, etc because even when you mount the exciters to a substrate they still don't comply with any of those parameters, at least not in a conventional sense. How do you do about getting complete set of T/S specs to make a ZMA?

Am I overthinking this or something because I learned how to do it with conventional loudspeakers and the rules don't apply to exciters in the same ways (or at all)? I would rather come up with tailored crossovers rather than just throw some basic crossovers together at given frequencies based on my far field measurements and call it good. Or is that just the best way because they are Bipolar, open baffle and not really phase critical?

TIA

It took me two days to find the bugger so I thought I would share it.
The WMP library function to update metadata only reads NEW metadata, not changes.

Windows + R for the run box
%LOCALAPPDATA%\MICROSOFT\MediaPlayer

You will then find all the cache for WMP, including Current Database.
So, to to a clean refresh of your music library, just delete this file. WMP will generate a new one with the metadata embedded in the music files.

Of course, you may want to modify that metadata. I used MusicBrainz Picard but I am sure there are others. Editing through WMP is useless. You can verify the edits in explorer by looking at each file properties/details. I found not always did the edit take, so verification.

The cover art is hidden files in each album directory. Easy to drop in new or change.

So, now I have genera that makes sense to me. ( Don't need to separate Jazz, soft jazz, fusion, avant-gaurd or whatever) Irish folk songs are not "world pop" and sorry Lesli Fish is FILK not Folk. And Wynton playing Baroque is not Bob.

Yes, I should look for another player. I have not succeeded in getting FOOBAR to display the covers like WMP. Several suggest J-River, but others say it is just as unstable. Audirvana was recommended as it bypasses the entire Windows audio path. ( No, not buying a Mac or building a Linux server)

Hi, just fitted a 100k TKD 2CP-2511 pot to replace an old blue ALPs, sort of expecting better things from an old scratchy pot.

In short I don't like it yet.

It sounds a lot less real/dynamic and musical. It has less warmth and bass and seems more shut in and 2D. It has lost all the micro-dynamics and tangibility and texture that makes it sound like live music. It has got a bit smother perhaps, but this is like an over-damped opaque smoothness quality. Sort of a bit like the classic passive preamp sound clean but lifeless, and constrained.

I have had to wire this in with fly leads, as it is not PCB mounted and at the same time I have replaced my power supply caps in the preamp as they were nearly 40 years old....so there are other things going on.

BUT I want my old sound back, I thought this would be better or at least the same, not worse.

It has not had much time to run in, so that's my only other hope

Thoughts?

Is this tidy, clean but dynamically controlled/polite sound a TKD character?

Hey guys,


So after thinking about it for years I have built my first ever amplifier, well half of it for the time being. It's a Mugen Hybrid (https://www.hobbielektronika.hu/forum/getfile.php?id=19235), it's very well documented. After powering it on, adjusting and testing the necessary voltages as the article said I had connected some cheapo speaker to test it and it worked, I could not had been happier. If I remember correctly initially there was no distortion or I just could not hear it, but eventually it became very significant, now whenever I power it on it's there. It becomes better as I raise the signal strength, but it's still there. Also, to my surprise the transistors attached to the heat sink remain very cold to the touch though I was not running the amp extensively.

My question would be, what should I be looking for? I have used the best quality parts I could find, but there are still some cheap parts which I could not source for the moment.

Here is a video to demonstrate the problem:
Mugen Hybrid

Here are the schematics of the amp:

I have tried to sim a TL subwoofer enclosure that HR calls an axisymmetric design.
Essentially a box with a pipe sticking out of it (at least I think it is; that is what it looks like).
The odd thing is I have input two different S3 variables and the programme has accepted that and calculated it.
See the attached, ignore the highlighted S4. And ignore the Comment too; the driver is RSS265-HO.
I'm not sure exactly what's going on here. Can there be two different S3 values??
The power response is pretty ordinary but in the LS Wizard with some stuffing I can get it to look really v nice. Slow rise to 40Hz, long flat response to 100 and then it tails off from there gently.

I have a QSC USA 1300 amplifier here of a friend. The B channel speaker relay is not engaging. At first I thought the channel is dead but after poking around with the oscilloscope I confirmed that its not the case.

Looking at the schematic it could be caused by a few things.

Anybody got some pointers for me whilst I am poking around some more?

Thanx in advance!

YouTube
YouTube

Need help with transformer that was in a Arcam AVR 350 240v model
with the wiring as determining what's what as all wires are black with little color tags except the green earth wire.
Its Noratel UK
P/N Tl- 053160 AU
A wiring diagram would be good if anyone has one.
Photos below.
Thanks
Glenn Kaspar
glennkaspar@gmail.com
gvkaspar@bigpond.com

With Bohdan's (creator of SE) permission I have built a Wiki and Forum for the software.

We are still working on finalizing setup, but please feel free to sign up and contribute.

https://soundeasy.chadgray.info/

Spread the word... 🙂

Thanks!
Chad

So last night I went to install some POT's on one of my 225's that just had resistors in place when I bought it. After that I figured I'd redo the wiring as it was a hack job but the amp worked. In the process of redoing the power wire I seen a spark go through the power supply and now I'm blowing fuses 🙁 . Just wanted to know before starting the troubleshooting process what the issue may be? Nothing was hooked up obviously but did I cause a ground?

Thanks in advance,

Paul

A lot of you will be aware but I saw this today whilst compiling an order.
UK VAT to be added from 22nd December.
Shame!

I am looking for a couple of Altec Lansing 30162 Throat Horn Adapters

I need a set to bolt up to my Altec 30146 Multi-Cell Horns.

"Trying to get all the parts togther to send out for blasting and powder-coating."

Any help would be appreciated. 😀

Hi. I need to order one chip for the US but the seller doesn't offer international shipping. It is from New York, small 14DIP chip, no big deal. Any help appreciated. Thanks
SB from Qc, canada

I recently starting thinking about loudspeaker systems with large/wide baffles. One concept that inevitably comes up is of the "infinite baffle". Strictly speaking, an infinite baffle is... well, infinite in extent, a plane. But is this really a helpful definition? What does this really mean for a practical loudspeaker.

Let's start with some thought experiments. What does the infinite baffle do? It subdivides the "space" into which the loudspeaker is operating. For example, you can start with "free space". This is something like being magically suspended in the air, infinitely (!) far away from any boundary. Now let's introduce a plane - the earth. Even if you don't believe in a flat earth, it's flat enough to be planar. Just by doing this the "space" that the air that the loudspeaker is operating into has been "halved". There is the "infinitely" large earth below, and the "infinitely" large atmosphere above. On the surface of the earthly plane, you are now in what is called "half space". Further boundaries can subdivide this space into smaller and smaller sections. Each time the space is halved, the sound pressure that is generated by a source is doubled, increasing by +6dB.

Getting back to the infinite baffle, if the baffle is also "infinite" then the baffle acts as one of these dividing planes. Think of an infinitely large open field, containing an infinitely tall and wide box with a driver installed on one side and "close" to the ground level. Of course this is just a thought experiment so far. No such real speaker exists. But if it did, the speaker's infinitely large baffle would increase the sound pressure by 6dB.

Now let's move from the theoretical world of infinite things to the human-sized world with real dimensions. What does an "infinite baffle" really mean? For the answer it seems that we can turn to Olson's well known 1951 article "Direct Radiator Loudspeaker Enclosures" for a clue. You can find it online. For simplicity let's consider his spherical enclosure. The diffraction signature of the sphere transitions smoothly through a 6dB rise as frequency changes from low to high (see Olson's text). The middle of this rise (the +3dB point) is often referred to as the "baffle step" frequency. It's essentially where the "baffle" (in this case a sphere) is starting to become "infinite-like" to sound. I say this because, just like the +6dB increase from an infinite plane, the sound pressure asymptotically reaches +6dB at high frequency. This is the case for any shape, not just for the sphere, in the high frequency limit.

So it seems like we can propose an answer to the question:
When may a baffle be considered infinite?
as
No less than the +3dB baffle step frequency.

I'd like to start a discussion about this topic here. Also, I would like to hear people's thoughts about the reason why the baffle step even exists. For example, Olson's experiments used a very small diameter source so that the radiation it produced would have very low directivity (e.g. like an omnidirectional source). Therefore, there is a component of the sound wave that is traveling parallel to and just above the baffle towards its edge. When the distance is small compared to the wavelength, we get the familiar cabinet diffraction effects. But it seems that for large distances, even though the edge of the baffle is still there, diffraction "disappears" and the baffle acts like an "infinite" baffle at that frequency as long as the distance is "large enough". This means that a relatively modest baffle can still be an "infinite" baffle at high frequencies. But what is the physics that is responsible for this? Because edge diffraction will be weak or absent at high frequencies and large baffle size, this will have some consequences for the radiation pattern of the loudspeaker to the sides and rear because these areas will only receive sound produced by the (front mounted )source via diffraction.

I think there are some interesting consequences to these ideas that are related to loudspeaker design and I hope there can be a in depth discussion about the points I have raised above.

I am having a hard time identifying what it is because it needs a replacement. My electronics repairman sent me this photo and said it is "LM31SH"

But there is no such a part available for sale anywhere on the net.

I have for sale a PeeCeeBee V4H amplifer (Rev. 1 PCB boards), precisely installed in nice compact enclosure. This amplfier is for sure, one of the nicest and compact built around. As proven with many group buys so far, this amplifier is very popular, due clever design and great high end sound.
Amplifier consist of 600VA (230V)transformer, made by my own specifications. Each power supply board consist of 4x6800uF 63V BC/Vishay capacitors and dual rectifier fast recovery diodes. For wiring speaker lines, Jantzen solid core wire was used. For indication two 2 mm green LED are used on front panel. Capacitors are Nichicon FGs and Mica, as Shaan recommends. Amplifier also has soft start circuit and DC protection build around uPC 1237 detector and Omron relays. Dimensions are: 32x37x9 cm (WxDXH). Amplifier is in perfect operating condition.

You can read a lot more information about this nice amplifier here, together with all measurements:
PeeCeeBee V4H GB

Specifications:
Power - 150W/250W into 8R/4R load with +/-56V PSU (0.1% THD)
Frequency response(simulated) - ~2Hz to ~800KHz (-3dB)
Slew Rate - 100V/uS
Offset variation - +/-10mV
SNR - >110dB
AC gain - 24.5 (28dB)
DC gain - Unity
Input level for 250W into 4R - 1.5VRMS (~4V P-P)
THD:
100Hz 10W - 0.0005%, 100Hz 100W - 0.001%
1KHz 10W - 0.002%, 1KHz 100W - 0.003%
10KHz 10W - 0.002%, 10KHz 100W - 0.005%

Price for amplifier 600 EUR + post costs. Payment via PP.

I have 2 toroids 120va 35v (amplimo) which i wanna use to power my ljm 2-12 boards. I don't need the full power of this amp.
I made a pcb layout with autocad for grinding a pcb.

1 toroid will power 1 amp board.

Pcb:
2 fuses (1 per rail)
4 schottky diodes to-220
2 led (1 per rail)
4 capacitors 4700uF 63v. (Nichicon audio grade for the looks)
2 capacitors 1uF with resistor 1R 3W.

Is this design any good for my application?
Should i add or change anything?

********* PRE-ORDER CLOSED *********

Although the pre-order is closed, regular orders are still accepted, but at regular price.

Regular Price :
- TU-8600S with Lundahl LL2785B + Pair of PCB Board + Pair of HV Connector $1,880.00
- Takman 2% REX50G Carbon Resistor Set $65.00
- TKD 2CP601S with conversion Kit $65.00

The response has been overwhelmingly positive.....
Thank you for your support. The pre-order will close on Sunday April 5, 2020.
I just found out that the LL2785B is $100 more than the LL2770. Also the suppliers from Japan will charge a development fee for the NEW PCB Board and manual for Lundahl OPT. These additional costs will further reduce the low margin. I need to stop the pre-order this coming Sunday. I will honor all pre-orders at the same price ($1,800) with the choice of TKD 2CP601S with conversion kit or Takman 2% Carbon resistor set. Once again, thank you for your unconditional support to our DIY PASSION...
Thank you for your trust and support....

Recommended Components 2020 Edition Power Amps | Stereophile.com
Extracted from Stereophile - recommended components 2020
EleKit Tu-8600RS: $1785 as reviewed ($1185 basic version)
As the name suggests, the EleKit TU-8600R is a build-it-yourself power amp, a single-ended design that uses one 300B directly heated output tube per side for a specified output of 9.2Wpc at 10% THD. (A pre-assembled version is available at extra cost.) Prices start at $1185 without tubes and top out at a $2985 version that includes Lundahl output transformers and deluxe German-made Elrog 300B tubes. Herb Reichert tried a variety of 300Bs in his Lundahl-equipped review sample and praised the EleKit for sounding not warm and soft but "fast and vigorous, as transparent as any amplifier, and extremely captivating," with a sonic character that's "clean, neutral, and precise." HR's conclusion: "This is what I call value for money." Other kits are available, but availability is sporadic. (Vol.42 No.4 WWW)


Please note that TU-8600S is a limited-edition product — with limited numbers allotted outside of Japan.

Only 100 pieces of TU-8600S are available in July 2020, and these can be upgraded with Lundahl C Core OPT installation.

Extracted from Lundahl Transformer:
The upgraded version of the Elekit 300B amplifier kit, called TU-8600S, will soon be available. In cooperation with VK Music we have upgraded our upgrade transformer, and are now busy winding the first 130 units of the LL2785B.

Lundahl Transformers - Lundahl Transformers LL2785B | Facebook

Factory glimpse An upgraded version of the Elekit 300B amplifier kit calle on Vimeo

ELEKIT TU-8600S AVAILABLE IN JULY 2020


+++++++++++++closed---------------------------------------------

• Your pre-order will be charged the day the kit is ordered.
• The pre-order deposit is USD $1,200.
• The pre-order charge is for the amp cost only (Lundahl not included, see below).

Pre-order : TU-8600S with Lundahl $1,800 (either TKD @CP601S or Takman REX 50G Free of charge)
--------------------------------- CLOSED --------------------------------


After Pre-order : TU-8600S with Lundahl $1,880 (TKD 2CP601S or Takman REX 50G is $65 each)

To customize your TU-8600S, upgraded parts and shipping can be ordered now and will be charged later (late June 2020):
• Lundahl with PCB Board and HV connectors USD$ 600 (after pre-order $625)
• TKD 2CP601S with conversion kit USD $65
• Takman 2% Carbon REX50G 81 pieces USD $65
• Coupling Caps (V-Cap, Mundorf, EHX ) TBD
• Tube set (Psavne, Gold Lion, EH Gold and ELROG) TBD
• Assembly service (optional) USD $275

To keep the price for you as low as possible, we are allowing cash in advance payment methods to our vendors in Japan. Lately, the USD to JPY is a financial roller coaster. To appreciate your supports , I will offer pre-order customer to pick the Takman REX 50G resistor set or TKD @CP601S free of charge. You can pick either option. This offer is strictly for pre-orders only. The margin for DIY is very low. I want to make this wonderful amp affordable to everyone.

Indeed, DIY audio is a very specialized market.

As a small firm with an enormous passion, we are attempting to offer the broadest range of kits possible to those of you who are equally interested in this unique pursuit of ultra-high quality audio reproduction.
Thank you for your support.

If you are interested, please email info@vkmusic.ca

From May 19th, 2020, the Paypal fee a merchant (seller, ie. us) paid when receiving payment for a transaction, is NO LONGER REFUNDABLE BY PAYPAL.
What does this mean to a buyer?
It means: when you place an order, for whatever reason you need to request a refund after order placed and paid, we can only refund you the NET amount we receive, but not the PayPal fees, that has been deducted by PayPal and no longer refundable to us.

Hello!
Anyone has tried the GR Research Open baffle sub for Quad ESL 57??

No high pass filter and just blend the sub with the Quad ESL to fill up anything under 40hz.

Thnaks!

Hi,
I have this receiver Kenwood KR-V45.

It has exactly the same fault shown here on a Kenwood KR-V55.

Kenwood KR-55R, EQ Fault - YouTube

Here is a part of the schematic:



Is this a common fault?

Does anyone know what clould be the problem?

Is this a capacitor issue?

Thank you for help.

Best regards,

Christian

Whats the difference between the 1 and 2 ohm versions of the stetsom amps?