FS: (Price Drop) Wynpalmer's OPA1656 and LMH6321 High Perf Amplifier

Hello,

I'm selling a fully built, ready to plug in, turn on and enjoy version of Wynpalmer's low cost, high performance amp using OP1656 and LMH6321.
This amp was built to spec, following Wynpalmer's BOM and is powered by a Silent Switcher, an excellent power supply with practically nonexistent noise created by Jan Didden. It is housed in a full aluminum enclosure which has a similar width as an O2, but with a bit more depth. Selling it due to lack of use (was my office amp, but changed office; it's also a good opportunity to invest in more DIY)
Features include an attenuator for volume control with 21 steps that uses 1% SMD resistors, one set of inputs, two sets of outputs (headphone and preamp out), a power button and a nice white LED for power indicator.
The theme here was aiming for simple, yet high performance. 🙂


Specs are:
(PSU)
9V 2A power supply that feeds into the Silent Switcher
4.7uV output noise

More at:
The SilentSwitcher | Linear Audio NL

(Amp)
Peak output drive current set at 270mA/channel
0.4W max into 15 ohms.
0.8W max into 30 ohms.
0.15W max into 300 ohms.
6dB gain.
THD+N @1kHz, 2v RMS output 80kHz measurement bandwidth: <-114dBc (0.0002%) A weighted.

More at:
Low cost, high performance headphone amp using OPA1656 and LMH6321


I am asking for 150€ plus shipping.


You can find more photos at the following link:
Imgur: The magic of the Internet

FS: Exponential Wood Horns (500Hz) for 1.4" compression drivers

A pair of exponential wood horns made from birch plywood treated with special oil.
Used in two-way speakers with 18 Sound ND1460A drivers, crossed over at 500Hz with LR 4th order filters. I've included measurements with and without a crossover (see last pictures), which proves that the original response of the drivers is not different.
This means that the horns themselves are completely transparent and do not add/subtract anything to/from the music! And most importantly, the quality workmanship and design exclude the typical horn nasal sound!

GIFTS: Flat top stands made specifically for them - check the photos where they sit on the speakers' cabinets.

A few properties:

• Diameter of the mouth: 57cm (22.5 ")
• Exit throat: 1.4"
• Depth of the wood horns (from mouth to throat): 28.5cm / 34.5cm with the drivers /

[comment]

[/comment]

Asking price for the pair: €750

Will be shipped securely via DPD to most European countries, but don't hesitate to ask me about your country.

========

Location: Sofia, Bulgaria
Contact me here or on email veselin.karavelov@gmail.com

I'd like to design a first order three way line level passive crossover.

I know how to get the calcs and make such a thing at the speaker level, but at the line level I don't know where to start.

A note - it doesn't actually have to be passive, but I want to avoid op amps. It can incorporated into the build of a Chinese knock-off NAC42.5 if that helps.

I need one piece of this chip...
https://eu.mouser.com/ProductDetail...oKKEcg8mMKGHUAmntboes/HX/W4gEcBJjZRntlsMORA==

STM32F446VE

If someone have in stock and want to sell...thx

Selling both pair of my Sonido SWR 096/A drivers. One set was temporarily hooked up to test free-air for about 5 minutes, the other is brand new never used. Essentially both pair are new, never mounted. I had planned on building a pair of speakers for myself and for my Dad but that never happened. I'm asking REDUCED TO $275/PR SHIPPED, $525 shipped for both pair (These are over $600 per pair from Sonido(which includes shipping and bank wire fee)). These are beautifully made drivers from Hungary with very nice sized alnico magnets. Even in free air testing I was super impressed. These are world class wideband drivers.

If anyone is interested in purchasing both pair I will supply a custom design along with ports, hook up wire, fiberfill, etc. to complete the speakers.

PayPal F&F only.

Selling a couple of tweeters.
$ 170 plus shipping.
Located in Ukraine.

I'm about to take a trio ka-3700 power switch apart to clean it and will replace the two 0.1 2000v caps that are placed across it.

What is the current advise on replacements? X2 rated at sensible ac voltage ~ 275v?

I've attached a relevant snip of the schematic my version is 'T' type 240v.

Here are video clips of performance of my handmade ribbon controller.

????? (Doraemon) Yuichi Onoue on Ribbon Controller (????,????) - YouTube
"Dawn of Ancient(??????)" by Kawasemi House - YouTube
Yuichi Onoue(????) "Ribbon Space" played on Ribbon Controller - YouTube
Ribbon Controller "Chimakiya(???)" by Yuichi Onoue(????) - YouTube




My ribbon controller is constructed three parts as follow.

"Ribbon controller" - which is made with a film of electric conductor
(like black paper which include carbon , or rubber conductive bag.
It is pasted to the vinyl chloride seat.)
Body is made by conduit pipe which is used at office etc.

"Handmade simple analog oscilator" - which is include NE555 as main oscilator, and cmos frequency divider.

"Multi Effect(KORG AX1G)" - Sound of my analog oscilator is like
poor buzzer. But it is processed various sounds by multi effects(like you listened on my youtube videos).

more about this Ribbon Controller, refer here(parts, schematics and so on) added on June 28th 2021
Self-made Ribbon Controller - unique electric musical instrument｜尾上祐一 Yuichi Onoue｜note

more videos are here. check it out!
http://www.youtube.com/profile_videos?user=TorigoyaSound

Please see also my home page for detail.
http://torigoya.main.jp/en_index.html

http://www.myspace.com/yuichionoue

Thanks

Hey Guys

I'm looking at repairing my A5 as it was full of salt corrosion around one of the SAP15's although the amp has been working!

I have striped it down and cleaned it up and found that C242 on the output board had blown and R12 on the input has fried, while I can see the value on the blown ceramic cap I cannot read the resistor.

Does anyone have a schematic or service manual as its proving hard to find!

I'm going to test all the transistors but as its been working I'm hoping there ok is there anything else I should check?

Thanks!

Let's say I have a large planar woofer, rectangular in shape. I have set tension on one axis much higher than tension on the other axis. What, exactly, would that do?

It would give you a double bump at the bass resonance, correct?

I have started reading the Self's book on power amp design, and at some point he analyzes a few non linear distortion models, such as the following:
Cubic distorion: Vout = (Vin)^3
Cubic + Linear distortion: Vout = Vin - (Vin)^3
"Stitched" square distortion: Vout = (Vin)^2 * sign(Vin) (to retain negative voltages)
Square root distortion, etc..
For each of those models, he states which harmonics are involved (ie. for the cubic distortion, the 3rd harmonic) and how the amplitude of the generated harmonics changes as a function of the input signal amplitude (what percentage of the output signal is the harmonics). I would like to know how to get these results mathematically. Thanks in advance.

Hi,

Just wondering how I could improve the connection between my home made preamp and its external 9VDC power supply choosing a better cable, but I do not know by what criteria to choose it.

Generally speaking I like to oversize elements and I would like to use a good cable suitable for that purpose.

Shielded or not?

Thanks for any addressing.

Hi,

Does anyone here have experience removing / replacing starlock washers? Obviously, you can get them off with brute force - but it can take ages, and collateral damage can result. A tool that puts them on / off would be very desirable. The things are a total PITA. A Google search throws up a couple of tools, but information pertaining to how useful they are is thin on the ground.

Any recommendations gratefully received.

TIA.

Wonder if it possible to change som values to make som more gain in this curcuit.
As it is now it’s +/-5db @ 50Hz and 10kHz. I would like it to be more gain (+8db?), especially in the bass and perhaps move the frequency up to 65-80hz.
And yes i know most lf the time flat or tone defeat is preferred but this is for my workroom and i just want some more punch/bass when i’m listening rock n pop (not any real hifi setup here)

It’s a NAD C162 preamp and i think many Nad share same topology so may it can help someone else too.


Best regards
Johan

Hi,

I am looking for a source selection rotary switch for my preamplifier project. I need to select between the 4 input sources.

-> Which types should I choose - Shorting or Non-shorting
-> How many poles are required?
-> How many decks are required?

NOTE
I am attaching the manual of a rotary switch I came across. It is a Non-shorting 4 Position 2 Pole switch. Is this Okay for my requirement?

---
Best regards,
BP

i have a thomson PA 3015 T amplifier that i had to replace its broken STK0039 with an STK0029, it caused the resistance "r634" 22ohm, "r633" 22ohm, on the side in which I've put on to overheat reaching about 160c° in just 10 sec, The temperature decreases as the volume decreases to less, I've also tried to replace it with STK0059 and still had the same issue, keep in mind that i dont have STK0039 to replace it with, and have replaced low Watts output STKs with higher ones with no problems in the past.
There is a resistance removed from the motherboard under a number "r935" and I don't know its value.

This model use the AD1955 DAC-IC - go to the images under
http://www.erji.net/forum.php?mod=viewthread&tid=476457&extra=pageD1&page=
This DAC-IC is burned.
Who can upload a schematic ?
Thank you very much.

P.S.: this thread don't provide the wanted information
https://www.diyaudio.com/forums/digital-source/111350-chinese-dac-yulong-da1955dac.html

i saw this chinese dac , retail for 2180 rmb before shipping
has any1 heard of it? if not , i want to buy it but can't test listen,would like to hear people's opinion on this dac
thanks in advance

● Standard input: Coaxial SPDIF, Optical input: USB-SPDIF，AES/EBU
●Input sample rate: 32-192kHz/16/24BIT Auto detection
● Signal to Noise ratio:>115db
● Dynamic range：110dB
● Total Harmonic Distortion：1KHZ%0.0005
● Rated Power: 2VPP
● Frequency Response: 5HZ-20kHz-0.2db
● Total Power >30W
●Dimensions: 430*270*65mm
●Weight: 5.2k

Hi Diy Audio Lovers

I soldered 4 Op amp sockets to roll op amps on my loxjie p20, I have tried SPARKOS SS3602 but they are all oscillating/making RFI noise.

But with V6 there's wasn't any noise(only slight hiss when turn on amp then all good) but the problem is its rated 16.v but P20s Ref voltage for op amps are 18v, I received an email from Dennis from Burson to confirm if I can use the V6 for long time use, but he said it'll get really hot and told me to use External Fans to cool down the V6.

right now im thinking about reducing the Reference Voltage from 18V to 16.V on P20 so I can use V6 Vivids/Classic opas without worrying about burning them.

Can anyone suggest me whats the best way to reduce the ref Voltage, should I use Voltage Divider using Registors on the sockets? Or is there any other way?

Please suggest me the best way I can reduce the Ref Supply voltage.

Thanks

WTB front end/preamp board for PRX518S bucket.

Good evening to all!

I want to migrate to ON\IN WALL speakers in a 13x21 room.(3.1 to 5.1)
Moving on from KEF q900 floorstanders and and corresponding Center Channel. VIA Yamaha RX-A830

More kids on the way, need space!!!!

IM mostly interested in Music ( Jazz , pink floyd, etc..) more so than HT. I like the fullest sound a the lowest volume.

Need
1- On\IN Wall recommandations (DIY also welcomed)
AMP\processor recommendations, will be streaming media via Apple TV, FIRETV , WINDOWS based laptops


Budget is 3-5k

Thank you all for your inputs!!!

Hello everyone,

I have a subwoofer 15" I made myself and use a BK sub amp, and want to reduce the quite dramatic room mode that is created.

I prefer the high level (signal from power amp) sound and am not that keen on using a DSP. I have an in room measured with REW software and can see a good solution for a high Q [5] notch filter at 32 Hz BUT how do I best make one?

The plots on REW are from a measured in room response and then with a filter added at 31.8 Hz at - 20 dB with a Q of 5.

I found this https://www.ti.com/lit/an/snoa680/s...047&ref_url=https%3A%2F%2Fwww.google.co.uk%2F old article but apart from that I am a bit lost.

Any ideas, I am not an electronics person by training or experience but can solder and am logical and practical. 🙂

Great!

Toshiba HN4A06 as diff pair
Toshiba HN4C51 as the current mirror

anyone see problems with using these ? will be feeding from current source LND150

Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.

What are your opinons of Dayton drivers vs. some of the better known drivers from Europe such as ScanSpeak and Seas? All my speakers are either Vifa, Scanspeak or Seas so I would like to know how the Dayton's compared?
The European drivers are so expensive nowaday that the costs just do not justify.
Besides the Daytons, what are some of the alternatives at lower cost but decent performance?

This listing is for a pair of fully populated Chipamp.com LM3886 amplifier boards as well as the associated power supply PCB and 10,000uf/50V main filter caps (not yet soldered in place). Asking $90 including shipping in the U.S.

I’m building a small kit radio, just as Shango066 did on his YouTube channel for those of you who watch him. I’m stuck on these last two transistors. They have no markings other then they both have a yellow dot on the back and one has a yellow dot on the top and one a green dot on top. I know that they’re both KT3107, but it appears there are different ones.

Dan

Working on a pair of Altas amps, I found shorted SGSD100 BJTs on the negative side on one of the amps. I have on order, 2STW100 to replace all in this amp.

In the meantime, I moved one of the SGSD100s from the positive side to the negative side for further testing. I then placed a TIP102 on top and cut the trace to the gate of the SGSD100 to help increase drive, as I have another Atlas that was already modified like this. The modification doesn't help though.

The main rectifiers have either +-41vDC, or +-64vDC on center legs. With no signal, I get +-41vDC on rails of the output BJTs, but then when I drive signal into the amp, clipping, I see +63.5vDC, and -51vDC. So, something on the negative side is not driving rail voltage to full -64vDC.

Then on the second Atlas VII amp still in the sync that I have, its a slightly similar issue, but both rail voltages go only to +-55vDC when driving full input. I would have expected closer to +-64v. from both amps.

Anybody have a suggestion for these older Vari powersupplies? Both amps play sound otherwise.

This is now SOLD. Thanks for your interest.

A like-new Outlaw Audio 7140 amp. I used this gently for only 1 year to run a DIY loudspeaker system before moving across the country, and haven't used it since then (about 3 years). It's been safely stored in the original MFG packaging ever since and I am looking to find it a new home.

Stock Photo:



INFO:
This is a great class AB amp for a multichannel setup or active loudspeaker, and has both balanced and unbalanced inputs. It was built by ATI for Outlaw and offers a capable 7 x 140W/ch into 8R, all channels driven. I like its understated looks, as opposed to lots of garish blue LED lighting that has become the norm. Specs and detailed pics can be found here:
Model 7140 Seven Channel Power Amplifier

I have included a few pics of the amp as evidence of the like-new cosmetic condition. There is nothing that I could find to report about. Sorry if some of the pics look like its "bent" - that is thanks to the lens of my crappy mobile phone. It's in perfect working condition as well.

SHIPPING:
The package measures 23x21x12 and is 63 pounds. Shipping expenses will be paid by the buyer. I will ship to addresses within the continental USA, using the manufacture packaging - its double boxed and the amp sits in custom urethane foam blocks. I can ship via USPS or UPS ground. Local pickup can also be arranged, and is both free and welcome after payment has been completed.

Please feel free to PM me with any questions you might have.

Here I have a collection of Modushop/HiFi2000 Galaxy case parts. There are no front/rear panels though.

• 2x 40x280mm sides, new
• 2x 80x280mm sides, raw alu, new
• 2x 80x280mm sides, black, new
• 2x 80x280mm sides, black, used with some holes
• 6x 230x280mm top/bottom panels, 2 used, 4 new, all 2mm alu
• 2x bags of screws, I think enough to make 3 or 4 cases completely

60 EUR, payment with paypal (buyer pays fee or send as F&F) or bank transfer

Postage: 6 EUR in Germany, 16 EUR in EU

Hi all! I recently picked up a pair of Hales Concept Three speakers where one of the woofers is completely missing. The woofers used were specific to HDG: "Focal 8KN515J - HDG". They are an 8" composite cone using Focal's older truncated frame.

Does anyone know of a supplier that carries similar New Old Stock Focal drivers from this era, OR does anyone know of a suitable replacement?

Thanks!

Hello
I'm still searching for a problem in the Attached Circuit of the Fender Ultimate Chorus Guitar Amplifier. This one channel is Oscillating, the other, not. all of the components were still original. I had previously replaced Electrolytic Capacitors as advised by Members in a previous post, but the problem still exists, so I hav started a new post in the hope that someone can help!
Kindest Regards; Telnet100

NOW SOLD

Hi All,

I've been holding onto this for a while - for that 'project' that I'm never going to get round to!

So I thought I'd offer it up for sale here - as it would make for a very neat and tidy build for someone with the time.

The case is in very good condition, with heavy duty heatsinks and a thick solid aluminium front panel. Comes with:

1. Chassis with lid, screws, speaker posts, etc (as pictured)
2. 500VA Transformer ( Clairtronic 12093 - http://www.farnell.com/datasheets/17835.pdf for details)
3. 2 x DC rectified supplies with 6 x 12,00uF capacitors (total 72,000uF per board).
4. TFX ASX-2200 Soft Start

Located in the UK, asking for £100 + P&P (probably about £15 as it's pretty heavy!)



https://ibb.co/zZWR7Mx
https://ibb.co/LvsL6nJ
https://ibb.co/XWty6kZ
https://ibb.co/2MhTYMh
https://ibb.co/0t6QMXm
https://ibb.co/C7DG3Fd
https://ibb.co/NNrG7zW
https://ibb.co/sgJRjtF
https://ibb.co/3SmD20f
https://ibb.co/8YPf56c
https://ibb.co/jzC50HJ
https://ibb.co/sKTwvzH
https://ibb.co/swfDkGt

Hi,
I am looking for version 1.4 onward dump of the hex file and the bin file from a working ultra curve pro deq2496
The on screen message is that it is waiting for a firmware update, I already have version 2 bin and hex but not version 1
i would be really greatfull if anyone has the hex and bin files so that i can copy it to the eeprom
thanks once again

Hello All

I'm desperately trying to reproduce the PCB of the Bernard Corde Dagone 800 amps someone on the forum can help me re-fabricate 2 PCBs for these amps?
Thanks for your help.

For sale is my newly retiped Fidelity Research MC-202
I purchased it as due to being impatient while waiting for my Fidelity Research PMC-3 was having its diamond re-glued to cantilever as it was loose.
The MC-202 came to me sealed by Soundsmith with a fresh re-tip.
I used it for literally 20 hours max- and that is a stretch.
Has a cosmetic dent in the body- it was like this when I purchased it knowingly.
Sounds excellent, would like to keep it but I have been laid off from job…
Tough times for oil & gas in Texas….

This thread is a place to organize the important items such as the most recent schematics, BOM, shopping cart, and build notes. Folks are welcome to help me by posting what they think is the most recent and accurate data.

Original thread here:
The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB



Thank you in advance for your contributions!

I’ve recently replaced my V25 LDR boards in my DIY balanced preamp with the newly released V3 boards, so these V25 parts are available for sale. They are less than 3 years old, with light use. I have two V25 boards, each with LDRs for 4 inputs, plus the OLED display (which includes the IR receiver and rotary encoder) and appropriate connecting cables. To build a balanced preamp, you’ll need a case, input & output connectors, and a 12VDC power supply. Full documentation for the V25 is on the Tortuga website. The boards both have the latest version 235 firmware, and USB cables for future firmware updates are included. If you’re interested in a single ended project (one V25 board and the OLED display), I might break up the set, please contact me to discuss. $375 for the complete set.

A 5 min video of what happens when P3 is adjusted. Enjoy.

https://www.youtube.com/watch?v=CQG2j9fkr9E

Hi All, Ive been using the Linear Systems LSK 389A dual JFET for a while, it works brillinatly in my low noise audio amp.

Unfortunately I have just been informed that they are having problems fabricating all but the LSK389C version which will draw much more current in my design.

Does anyone know of any other low noise dual jfets that are comparable?

I'm waiting for parts to come in to breadboard this. In the meantime, I'd love to hear any thoughts.

Notes:

• Tubes are 6SF5 (half a 12AX7), E1148 (slight variation on 7193/2C22, so half a 6SN7), and 6DY7 (two beam tetrodes in one bottle, shared cathode and screens).
• This is my first design with a CCS that isn't under an LTP. Not sure I'm injecting GNFB in the right place, but LTspice says it's effective there. The CCS is set for about 1.34mA, which comes in at 1.4V at the 6SG5 cathode at idle.
• At a minimum, screens and bias will be regulated. I'll probably regulate the whole thing.
• LTspice says this will generate 22W at 1.2% THD from a 1VRMS input. However, that's probably over-optimistic, because it's got the plates swinging to 30V on the low side and the same distance from 2*B+ on the high side. Oh, and I also don't have series resistance in the OT model.
• The OT inductance ratios are correct for the modeled 16R speaker load. That's an artifact from when I was exploring different OT options, because this wants an oddball impedance (14k). I'll fix up the numbers for the 8R intended load.
• LTspice says the tubes are idling at about 19mA. That's very cold - half of the dissipation limit. The datasheet recommends -20V bias for 400V on the plates, but the only commercial amp to ever use this tube (Stromberg-Carlson ASP-422) indeed sits all the way down at -29V. I'm pretty skeptical - will have to work this out on the breadboard.

I have a Kicker Ix405d on the bench with blown power supplies on the class d side and the ab side.

The class D outputs are all blown too.

The z44n's are physically damaged.

I removed all the damaged transistors and the amp powers on.

I noticed there's zero resistance between the z44 source and drain pads on both power supply sections, is this how it should be before I replace with new z44's?

Thank you

Hello all. I just joined the site and I'm looking forward to learning how to work on some of my audio equipment on my own.


Currently I have the following components that need repair.


The Fisher 800T
Bel Canto EVO 2i
Arcam A65 Plus
CEC 3300 CD.


I'm trying to get a service manual from Bel Canto but I don't feel comfortable starting there with diy. Probably the same for the Arcam. I'll outsource those repairs or wait until I'm more comfortable.



I would like to track down a service manual for the CEC 3300 if anyone can be of help. I found a manual for The Fisher online.


I believe I have sourced the transport (Sanyo SF-P101N) for the CEC but have not been able to locate the belt at a reasonable price. CEC wants $100. Any help here would be much appreciated.


I'm going to start my DIY attempt with The Fisher and the CEC.


Thanks for any help or suggestions for getting started.

sacthailand.com

This is the version with standard transformers and in original condition, not modded.

Condition wise, there are some scratches on front panel and the roof of one tube cage is slightly depressed (see photos). The amplifier is otherwise in excellent condition with original tubes run at 25-30 mA bias (slightly lower than recommended 30-40 mA).

Originally bought from SAC Thailand in 2014. I'm selling because it has way to much gain for me (26 dB).

Local pickup preferred (item is located in Espoo, Finland. I offer listening and coffee!). I have all the original packaging/crates, but shipping would be on the buyers risk.

1800€

Hello everyone..
anyone has latest firmware of this media player?
Some network issues makes media faulty, getting SSL error etc... Company website do not exist..
Tia
Sivanand

Hi guys
I need your help in order to understand something
I tried to understand the differences between the no 33 and the 33H
And one of the differences is in the voltage regulation circuit that supply the input stage
At the end of the circuit you can see 2 electrolytic capacitors of 100V 330uf while in the 33H there isn't any...
Why is that ???

Thanks for all the replyers

Hi all,
I got my hands on an old Creative I-TRIGUE 3200 (Model: MS0760A). It came with a problem on the right channel; no audio was coming out.
When putting it apart, I found that in fact there was audio coming out of the right channel. However, when I tilt it in a certain position, then the audio is gone.
Left channel works no matter what.
I'm sure there is a most likely some crack somewhere along the right RC jack connection, but I can't determine where. I've refilled solder in some of those nearby traces, but to no avail.
I, sent a request to creative about this product, but they said they got no support nor documentation for the product as it isn't sold anymore. (I knew it was a long shot)
I was wondering if anyone:

1. Run into this same problem and solved it?
2. Propose a way to solve this problem?
3. Has reverse engineered the schematics for this product's board and doesn't mind sharing it so that I can guide myself on the signal path.

So far, I've realized that, if measure voltage at the two inputs (2 pins enclosed in red @ inkedright_channel_out_LI.jpg) with the respect to V- terminal, I hear hum on the right channel when the speaker is connected. Not sure if it means anything to someone more experienced.
They are also biased at approximately 6.2V, which seems reasonable since the input voltage is ~12V.

Thanks in advance

Hi,

Wish to build A new wooden plinth (also called "sub chassis"?) for my Thorens Td166 mkii.

But i really know NOTHING in this...only to make it.

Here I need the crowd helping:
Have you have found here or anywhere A sketch of the Td166 mkii plinth and remember where?
If do - a sketch & dimensions would be SUPER helpful!

I know only to work ... i dont know anything in sketching.

Thank you so much!!!

Is there a codex or method, or "secret decoding ring" to ScanSpeak drivers?

For instance, comparing an 18WU/8741T00 to an 18W/8434G00... "18W" is 18 cm woofer, got that... the first "8" after the "/" means it is an 8 ohm nominal driver... got that... but how would I decode that one is an Illuminator and the other is a Discovery? what do the other numbers and letters mean?

j.

I am very confused . . .


I just purchased a Hidizs S9 Pro DAC Dongle, and want to use it with my smartphone to play music. The manual (for the DAC) says "Just plug it in."


Well, the DAC cable is USB-C (at both ends), but my [older] Samsung phone has a microUSB connector. Do I buy a microUSB-to-USB-C cable, or can I use the 3.5mm headphone output on the phone? I'm assuming the headphone output is already analog, and don't know if that can be over-ridden to output a digital signal.


Assuming I go with the microUSB output, do I need just an adapter, or an OTG cable? I don't seem to be able to find an OTG microUSB (male) to USB-C (female) cable. Can I go with an OTG microUSB (male) to USB 2.0 (female) and then use the USB 2.0 adapter that came with the DAC? That kind of leaves me with a very kludgy system . . .

I'm not sure where to post this, so I'll start in the Lounge.

I want to build a portable call for hunting coyotes, but I need something with a good remote control I know I can buy a good one for about $400, but being a DIY guy, I'd like to build my own and save a lot of money. I'd like to be able to operate from at least one hundred feet. Any ideas on a portable amp with a good, strong remote control?
Thanks!

I just built this amp and sounds very nice, can anybody see any problems??

So after reading DIY speaker switcher I decided to build one my self. Its working well and I'm using 12 pins toggle switcher, since almost all the tutorial use that.

But I came across this switcher which only use 6 pins toggle switcher, and it seem that they shorted the negative connection together. Does this design have downside? I want to build one like this but don't want to fry my amp/speaker.



Thanks

DIY Kit AudioResearch ARC Tube Preamplifier Balanced/RCA IN&OUT,12AU7/ECC83+ECC88/6DJ

Hi there,

till now I did more reading than writing but today I need some informations about this what is called a ARC-preamp kit.

https://www.aliexpress.com/item/1005002553663346.html?spm=a2g0o.cart.0.0.58ad3c00858gF4&mp=1

Even if I doubt that there is a real complete ARC schematic behind it, there could at least be some approaches. But the more important point is that there is also a suitable housing for the kit which makes it more interesting.

I have already created a few tube projects (HiFi- & guitar-amps) but the housing work with normal tools is not that easy.

Does anybody know what's behind that circuit diagram in terms of audio (the periphery pcb is more of a welcome addition)? Is it worthwhile?

Cheers
Claus

dbl post

Does anyone have any first hand experience with the Heissman Cinetor-Evo speaker?

I'd like to try a waveguide speaker and even though I really need 8 ohm I'm intrigued and tempted by this one. The components are surprisingly cheap to get sent from overseas.

Thought you guys might enjoy this chat I had with @Floyd Toole a couple days ago.

Thanks to Dr. Toole for being a sport and entertaining my questions and generally being such a nice fellow. Hopefully we can do this again sometime soon. 🙂

I'll try to add timestamps when I can. But for now, I simply don't have the time.



Chat with Dr. Floyd Toole - YouTube

Early AC/DC and Bon Scott on bagpipes. Classic.

AC/DC - It's A Long Way To The Top LIVE On TV 1976 - YouTube

I am on the verge of building my first set of speakers and had pretty much plumpt for the SB Acoustics, either SB15NRX30 or SB15MFC30. Recently though, I have been looking at the Satori MW13P, which appeals to me being a smaller driver but still having reasonable Fs, and wondered if anyone has compared these drivers and could possibly offer opinions on the quality difference and whether they're worth paying twice the price for?

Thanks!!

Hi, many of the amps discussed here are stereo amps, such as Aiyima A04, Shui Yuan amp, etc. How do people typically use active subwoofers with these amps? Or do people not use subwoofers?

I have two seperated pcb one is power supply pcb and the other one is noise sensitive DAC pcb.

I put vias on both pcb to make a pin to pin power connection please see attached picture.

In power pcb i use noisy isolated dc/dc converter (switch freq. 100khz). To clean up noise, i use LC filter + cap multiplier right after isolation and then a linear regulator.

I must connect power supply ground plane to the DAC pcb ground plane. The question is, which location/locations is good to do that on both pcb?

Hi I’m needing a schematic for a Acoustic 114 guitar amplifier. If anyone has one could you share it?
Thanks

Sorry guys, instead of adding to a 2 year old thread I thought I'd create a ne, especially seeing the intention has changed a bit from when it was first started back in 2019.

Over the last 12-18 months I've made a few different things and went down the rabbit hole of 3d printers and small bt/amp boards.

On the topic of both I've been flirting with the idea of a beer can speaker , which is around 0.015cuft volume, uses a 2 inch peerless driver from a Google home and powered by a QCC3008 BT/Amp chip (which is a 5v board). I've tried many variants to date which can sizes, a few of the csr version amps, drivers, passive membranes, vents etc as well, but think I have my combo ready now,

TLDR I'm using and have a programming device for the QCC3008 amp and wondering if there are any settings in the attached image to mimic the performance of a.soundlink mini, either via EQ settings, bass boost, crossover etc.

I fear with a lack of TS specs available for the peerless driver due to being special order, that the enclosure may be undersized, but want some good sounding low end at all volume levels, which might be starting at 100hz and above considering the size, with a roll off for some od the lower end from there.

I would love to hear any suggestions in tweaks to the amp via the USB SPI programmer I could do to make this battery powered lowfi device next level.....I'll share the STL'S as well If people want to develop their own and share what they've done

Hi all,

Quite a while back I built a preamplifier that I am pretty sure I learned about on this forum. I think at the time I had built an Aikido linestage and was interested in preamps. Anyway, I built one designed by a member here, Poindexter, that he had christened Moebius and used 6T4 valves. I think a version was available as a commercial preamp and got good reviews at the time. Anyway, the preamp had been in storage for many years now, and in the course of a tidy up, I pulled it out for a look and to check it over today.

Suffice to say, it is clear from revisiting this old build that I have learned a reasonable amount about building in the last decade! After a fair bit of tidying up functional but janky wiring, improving grounding and redesigning the HV supply, its sounding very capable now. I'll give it a soak test for a while to make sure its stable.

Anyway, none of that is why I'm posting here, the real reason is that no matter how I searched here I couldn't turn up a schematic or a build thread. I eventually found the schematic on a Polish forum, and thought I'd post it here - along with the question - have others here built this pre? Anyone still got it in use?

Fran

I am working on an OTL headphone ampifier with 6SN7 for input tubes and 6AS7 in push pull for the DC coupled output stage. Since this also mean I have a risk of having b+ voltage send straight to my headphones I would like to keep the voltage as low as possible.

I have already fitted a diode/TVS clamp on the output for safety but would also like to keep the b+ voltage low, but how low can I go with the 6AS7 tubes?

I have seen designs from TubeCAD with +/-50V but can i go lower? And what would the consequences or effects of low voltage be? And can I trust my tube models at such low voltage?

The input tubes will still be allowed to have high voltage and will be AC coupled to the output stage.

Buffalo II DAC with NTD1

For sale my up to now reference DAC. It was build with as good as it gets parts.
Susume RG smd resistors
Caddock MP930 power resistors
Matched output transistors from GB
For PSU regs upgraded to LT1085/LT1033 from Farnell
PSU includes 4 regs for output stage and 1 as raw power supply for Buffalo
You only need to add trafos, I have EI transformers but I reckon they are too heavy

Buffalo DAC was upgraded with LT3042 regs (Dimdim's pcbs)

Measures and plays perfectly

SOLD

Many will say: another TPA3116 amp?

Well, I already have one 3116 amp from Breezy Audio, but I need to install one for bedroom TV setup, and it has to be Bluetooth, which the Breezy does not support.

This the one I'm talking about:

https://www.aliexpress.com/item/1005001708649867.html?ug_edm_item_id=1005001708649867&creative_img_ind=3&creative_img_tpl=153709&edm_click_module=alg_product&tracelog=rowan&rowan_id1=spaml_product_2_picture_square_2_1_pt_BR_2021-07-24&rowan_msg_id=carlCOWS_220_$f08acb0364e94e4faa4e602f62e09931&ck=in_edm_other

Has anyone bought one and is already using?

They mention that you have to install the protection and the heatsink, but do not show what that is or seem to sell it or show it. Does anyone know what they are?

The problem is this: I have a Semp Toshiba TV and it has BT. I have two sources that I have to feed in, but I have to find a way to amplify the sound from both for the external speakers. I did that in the past, but it required two additional boxes and additional power supplied, and available is critical.

I don't trust the quality of the TV's headphone which I could link the amp to, so BT might an option. How's the quality of BT audio for that application?

Well, I asked several questions, so let's wait if I start getting answers.

Thanks!

Curious if anyone's heard of this driver. Not much comes up on searches and know some of the Celestions performed admirably in the past. I presume it's a 1.4" diaphragm and it's a 1" exit... Is that about all I can deduce from the part name?

Any help, or clarifying would be much appreciated.

If Wined is ok with using his 3D CAD file (I just asked for his permission)

https://www.diyaudio.com/forums/gro...r-se-bal-se-bal-buffer-gb-22.html#post6711584

- I would get at least three BTSBs. (Maybe four/ five?) …

I haven’t yet got one for either of my two TPA amps; one of which is a 4 channel - so it alone really needs two BTSBs (which xkr generously got working and tested, taking a bit longer than the agreed time cost allowance)

Plus, I’ve got three power amps with gain of just 14-20 dB (and another likely lowish gain amp underway!)

And, a very good Musical Fidelity preamp with an excellent * passive output, but the active line output is noisy. I’ve been wondering what to do about that %#! for a couple of years now!

(And purchasing parts & making things in batches … productivity & the work rhythms are better)

Wined’s custom CAD designed case is the perfect size for the TH board. And while I could probably master SM, that would take longer … but the Etsy store doesn't list them at present. When might there be another run?

Hi all. Today is a sad day for me. I need sell my csx1 stuff. I sold complete as is. Not for sale only vfets.
They are matched for csx1...
2sj28 KE '25' VGS 6,84V
2sj28 KE '26' VGS 7,67V
2sk82 KE 'A' VGS -7,8V
2sk82 KE 'B' VGS -6,37V
Almost perfect pairs... Difficult find today these matched pairs
Two 25V-25V 250VA trafos
Two Permaneder csx1 boards with 2sk170BL and 2sj74BL soldered.
Two JT-123-FLPCH Jensen trafos
Four Nippon Nichicon 33000uf/50V
Two IRFP240, two IRFP9240

Price... 400 eur + shipping + paypal fees

I'm really enjoying my Dennis Had designed SixPac monos, but I do want to roll some other power tubes in it without burning my wallet to a crisp - a full set (12) of Psvane EL34PHs would set me back a cool 900GBP.

So, I was looking on the internet for the possibility of running it with only a single pair of EL34s per channel (the amp has 3 pairs by default). I came across a great video on youtube (on the MrCarlsonsLab channel) where the amp was opened up, analysed, reverse engineered... the works. This confirmed my knowledge that the output tubes are paralleled, but I couldn't understand exactly what's the purpose for this arrangement. In theory, I could easily remove one or two pairs from each channel and run it like that (after adjusting the bias of course).

Some time ago I removed a pair from one channel, as an experiment... and I expected a drop in output power, but I couldn't notice one. Not understanding what happened, I just put the pair back in and used the amps as designed.

However, I'd still like to understand this, as running it with less tubes (cooler, cheaper) would make sense to me, if performance isn't affected (except output power, which I have enough of anyway).

I've attached the reverse engineered schematic for reference.

Cheers!

FS:Lots of Bc327 and Bc337

2 bags of Bc327 and Bc337,don´t know ho meny but maybe 150-200 each bag.
15 Euro + shipping for the lot.

Hello,
My first project was the Pensil Alpair10p. I have been listening to these speakers the past year and enjoy them very much. As you know they are great with vocals and single instruments music but don't do well with more complex music such as rock which I listen to mostly. I understand the limitations of fullranger and accept them.
As for my second project, I am looking for higher end driver in the $1000/pr price range to build as 40L-50L standmount monitor to match my 6 watt SEP EL84 tube amp. The 2 that come up regularly during my searches are the Supravox 215 RTF and the Jordan Eikona 2.Both have great reviews but will they match up with my 6 watt amp?I have my doubts.The Jordan's sensitivity is 86db and I read that they need current to sound their best.
The Supravox look like a better option in a bass reflex monitor with a Qts=0.46 and sensitivity of 98db. I read that ideally a driver with a Qts = .27-.35 is best for a ported enclosure.I will let the more knowledgeable DIYer comment on that.
Are there better drivers than the Supravox for my intended project?
I appreciate your comments

This thread is for "How to build a Balanced B1 Korg Triode" preamplifier.
First, the hardware, I purchased two sets of PCB w/FETS and Korg Triode tubes from the diystore. Boards were stuffed the parts from the BOM with Nichicon UES 1000uF filter caps and Panasonic 10uF film caps (these were the extras I mistakenly bought while building a BZLS).
Once both boards were stuffed and the test voltages confirmed for both boards, I marked one board for Left + and Left -. With the other board marked Right + and Right -.
I measured each side of each board using REW software, Akitika 1K generator and a Behringer UM2 sound card, for 1.5% 2H negative, 1% 2H negative, null point of 2H, 1% 2H positive and 1,5% 2H positive. Here are the results:


R+ R- L+ L-

1.5% 8.57 vdc 8.61 vdc 8.84 vdc 9.51 vdc

positive 2H



1% positive 9.53 vdc 9.52 vdc 9.41 vdc 10.53 vdc


Null 2H 11.62 vdc 11.43 vdc 11.41 vdc 11.57 vdc

0.043%


1% 12.44 vdc 12.12 vdc 12.30 vdc 12.30 vdc
negative 2H


1.5% 13.07 vdc 12.50 vdc 12.84 vdc 12.70 vdc
negative 2H


This is the same procedure I used for my B1 Korg Triode preamp, the hard part was adjusting each channel in balanced mode.

I was lucky enough to get my hands on two “essentials” kits for the VFET amp build made possible by Mr. Pass and the diyAudio store in this thread. Putting together the components for the build, I realized that I have plenty of matched pairs of Toshiba 2SK2013/2SJ313 and Vishay IRFP240/IRFP9240, to offer these to interested builders at a good price (28 euro for the four pairs + postage).

These FETs are substitutes for those already included in the supplemental kit made available by the diyaudio store (unmatched Fairchild FQP3N30/FQP3P20 and Vishay IRFP240/IRFP9240), so if on a budget please do consider if you really need these.

You will still need the VFETs provided only as part of the essentials kit and you will also still need the 2SK170/2SJ74 Jfets or the LSK170/LSJ74 equivalents provided by the store as part of the optional supplemental kit.

As long as I have devices available, I will keep a link here and in my signature to a sheet with the devices specifications and ordering instructions.

Update November 28th:
I have had contacted by members asking if I can sell the K2013/J313 pairs separately and if I could also possibly also provide authentic 2SK170BL/2SJ74 pairs to complete the kits.
I can sell separately the 2SK2013 and 2SJ313 pairs for 20 euro (for the two pairs).
Also, for members taking these kits I can provide pairs of authentic 2SK170BL and 2SJ74BL (Idss matched) for an additional 36 euro. As long as stock lasts....

Hi,

Purchased these from a chap on here some time back. Was going to use in a project, but no time for that now...

Have two boards available £20 for both, plus P&P

Please let me know if you need any other information.



https://i.ibb.co/7QgfnVX/IMG-6519-2.jpg
https://i.ibb.co/fM4Gchh/IMG-6518.jpg

I just built this today and sounds as good as the 6l6 6h9c i built , again if I have done something wrong please comment and tell me if wrong. Bass is very strong mids to high are also very good.

Hi,

I need some input....I was gifted a Luxman MQ68C a while ago. Originally, the power tubes are the obsolete 50CA10 in triode mode push pull fixed bias with a plate voltage of 400VDC and a 6K OPT. The tube is capable of 35W in that way, Luxman rates the amp at 30W. The original tubes are long gone, and the Chinese replacements have a dubious reputation and are not inexpensive.

I have been putting this project off because I am not happy with the idea of running EL34 in this amp. I did install a 6A 6.3VAC transformer to power the new power tube heaters, and installed octal sockets. The PT has a 0-360V 280mA HV winding on the PT, the 50V heater will be released from duty, reducing stress on the PT.

The original EL34 would put out 19W according to the datasheet, and new production tubes would obviously be less.
The alternative is 6550 in triode PP, this does around 25W, still not at the 35W mark for the 50CA10.

The KT88 does not fit, the sides of the bottles touch. *yikes*

So then I looked at alternatives and came up with two options that I am considering:

1) KT90 biased at 50-60 mA in triode mode. The skinny bottles fit well in the amp.

2) JJ EL509S in Enhanced Triode mode (screen driven). This way, the bias current will be about 10mA per tube and this will make the PT run much cooler. I may not have enough drive from the inverter to get enough power from this tube. But that can be fixed with a Mosfet.

Has anyone done this before, or anything similar? What are your thoughts on these approaches?