3E Audio 260-2-29A : TPA3255 / HA3588 CoilCraft / PFFB Fully differential.

[daniboun]

Colleagues, I am very upset... Topping PA5 arrived and I decided to measure the distortion of amplifiers 3E and PA5 with the ARTA program. The 1 kHz test signal is recorded on a CD and played back by the E50 DAC. Test results in the photo. It can be seen that the left channel of the 3E amplifier distorts greatly, while the PA5 has no distortion on both channels. I'm not a fan of Topping, but what to do with the 3E amplifier now.

Please specify the reference of the 3E Audio module tested so as not to mislead people? as well as the test conditions, otherwise it doesn't make much sense here...
I invite you to read the measurements of S=klogW on page 1 for example

It's as if I were telling you, I tested a Topping amp... without specifying the model) (you can share pictures, better)

 

[daniboun]

The article number of the amplifier board is given in your messages, it cannot be different.
The test conditions are given above, in more detail - power 5 W, load 4 Ohms, ADC Kosmos E1DA, ARTA, test signal 1 kHz recorded on a CD, SPDIF DAC Topping E50. I Replaced the power supply of the 3E amplifier with a PA5 brick, no change in distortion.
The right channel 3E is more or less normal.

Can you quote the reference of your module rather please? Please share a picture !
EAUMT-0260-2-A or 260-2-29a ? : They are completely different modules.. there is a huge gap between the two....

What's more, on your attachments, we see PA5-II displayed and not PA5... you say you tested with the PSU of the PA5 that has a GX type connector....

We are waiting for your pictures please

 

[UAN]

260-2-29a PA5-II
I deleted my measurements, the amp sounds good and ok... Once you assemble the amplifier, be sure to test it.

 

[daniboun]

260-2-29a PA5-II
I deleted my measurements, the amp sounds good and ok... Once you assemble the amplifier, be sure to test it.

Hey, I didn't really understand your approach) but it doesn't matter lol
I always test my components before fixing them in the enclosure ) I also do continuity tests when I assemble my cables as well.

 

[UAN]

Эй, я не очень понял твой подход) но это не имеет значения, лол
Я всегда проверяю свои компоненты, прежде чем закрепить их в корпусе ) Я также провожу тесты целостности цепи при сборке кабелей.

Здравствуйте, я удалил свои измерения, потому что мое оборудование не сертифицировано и размещать любительские измерения на таком авторитетном сайте некорректно.
P.S. Что касается звука, то усилитель 3E мне нравится больше, чем PA5 II.

 

[daniboun]

Thanks for the picture. Dont forget to ground the TRS/XLR plugs this could explain the noise you have in both channels) The same for AC in, it s more prudent to ground it too.

My amp is almost finished. Will share pictures by the end of the week. -)

 

[UAN]

Спасибо за картинку. Не забудьте заземлить штекеры TRS/XLR, это может объяснить шум, который у вас есть в обоих каналах) То же самое и для входа переменного тока, более разумно заземлить его тоже.

Мой усилитель почти готов. Поделюсь снимками до конца недели. -)

Корпус штекера подключается к корпусу усилителя через розетку TRS, то есть заземляется. Что значит заземлить сетевой вход?
Высокий уровень шума, 125 дБ, — это шум генератора, то есть проигрывателя компакт-дисков.

 

[daniboun]

Корпус штекера подключается к корпусу усилителя через розетку TRS, то есть заземляется. Что значит заземлить сетевой вход?
Высокий уровень шума, 125 дБ, — это шум генератора, то есть проигрывателя компакт-дисков.

A balanced interface normally has three wires:

1. Reference (usually ground)
2. Signal (hot)
3. Inverse (cold)

As you can see, you left a cable disconnected (ground)

 

[S=klogW]

Корпус штекера подключается к корпусу усилителя через розетку TRS, то есть заземляется. Что значит заземлить сетевой вход?
Высокий уровень шума, 125 дБ, — это шум генератора, то есть проигрывателя компакт-дисков.

Not sure when we became "Обзор Ayдио Наука" but with Google Translate, I think I've got the jist of your question/statement written in Russian.
You say you only get a 125dB noise floor because you are playing a CD recording of a REW test sine wave out of your CD player into the 3eAudio amp.
I would suggest you upgrade to an old PC with a cheap modern DAC as your test source. Either borrow one from a friend or do like I did and buy a
very cheap broken one and fix it. That way you will be using measurement instrumentation more appropriate for high performance amplifier testing.

 

[daniboun]

Not sure when we became "Обзор Ayдио Наука" but with Google Translate, I think I've got the jist of your question/statement written in Russian.
You say you only get a 125dB noise floor because you are playing a CD recording of a REW test sine wave out of your CD player into the 3eAudio amp.
I would suggest you upgrade to an old PC with a cheap modern DAC as your test source. Either borrow one from a friend or do like I did and buy a
very cheap broken one and fix it. That way you will be using measurement instrumentation more appropriate for high performance amplifier testing.

Thanks for the decoding and clarification )))
But I still maintain what I said, it seems important to me to assemble an amplifier correctly before using it...
I still invite UAN to follow your recommendations and to correctly connect its TRS plug )

 

[S=klogW]

Thanks for the decoding and clarification )))
But I still maintain what I said, it seems important to me to assemble an amplifier correctly before using it...
I still invite UAN to follow your recommendations and to correctly connect its TRS plug )

Completely agree daniboun! Assemble correctly; test solder joints with a multimeter for dry joints; make sure that sub-assemblies share a low impedance signal-return ground by use of the hot, cold and ground balanced signal pins; make sure the you try star-grounding if you are still getting "mains-hum". Only THEN use test equipment appropriate to the task. UAN says he has Ivan's E1DA Cosmos ADC, so that's very good. However, Ivan has in the past said that using ARTA can lead to measurement inaccuracies and he recommends we use the (free) REW Real Time Analyser for THD+N measurements.

@UAN, do you still have distortion in one channel? Did you perform the lowering of gain that you asked me about in your earlier post? If you did then please test with a multimeter that you still have signal continuity after the swapping of Rin; Rf and Cf that I explained.

 

[antcollinet]

Not sure when we became "Обзор Ayдио Наука" but with Google Translate, I think I've got the jist of your question/statement written in Russian.
You say you only get a 125dB noise floor because you are playing a CD recording of a REW test sine wave out of your CD player into the 3eAudio amp.
I would suggest you upgrade to an old PC with a cheap modern DAC as your test source. Either borrow one from a friend or do like I did and buy a
very cheap broken one and fix it. That way you will be using measurement instrumentation more appropriate for high performance amplifier testing.

Bit confused how there can be a -125dB noise floor with 16 bit redbook source. Perfection with 16 bits is around -96dB

 

[S=klogW]

The other product of bitter experience that I've been meaning to share with all here is that : How you wire your new amp's output to the measurement test fixture is very important when measuring the very best in modern power amplifiers, and TPA325x chip amps with PFFB like the 3eAudio 260-2-29a are members of this exclusive club.

@amirm first explained this when he first reviewed the Benchmark AHB-2 which alerted us to a Brave New World of power amplifiers. Amir said "The performance was so good I literally had to rebuild my dummy load to get there. Even the quality of the metal used in the connectors matters to get to this level of distortion. I replace all my dummy loads with higher precision ones that have much less VCR (voltage coefficient of resistance). Resistor values can become voltage dependent creating distortions of their own. Up to about 105 dB of THD+N, it doesn't matter but beyond that, the VCR was the dominant distortion, not the Benchmark AHB2 amplifier!"

So I use a number of the modestly priced Arcol LPR100 Low VCR; 100 watt, 8ohm resistors and serial/parallel them to make the appropriate dummy load for each test.
I also clean and solder all connections (temporarily for the measurements) not trusting crimp connectors or binding posts to give the most reliable/lowest resistance electrical connections required for high performance audio equipment testing. BTW Have you ever returned to your bare wire and binding post connections after a month or so to find your Herculean finger torque has inexplicably loosened to a feable nip or that delightfully coloured, verdigris copper corrosion has appeared at the interface?

 

[S=klogW]

Bit confused how there can be a -125dB noise floor with 16 bit redbook source. Perfection with 16 bits is around -96dB

If @UAN uses, say, REW Generator to make his 0dBFS 16-bit 1kHz test signal, he can select to tick the "dither" option. In theory he might squeeze a -120dB noise floor from 'ideally-dithered' 16-bit with a very performant CD player as source. -125dB, though, is a real stretch/not gonna happen.

What is dither, and is it still relevant in the Hi-Res audio age?

Dither is an audio concept that, aside from producers and audio engineers, few people truly understand. We explain why it remains relevant.

www.soundguys.com

 

[daniboun]

Thank you for these explanations. No room for chance when it comes to measuring properly ) I believe, however, that the good rules of practice also apply when assembling. Do not neglect to twist the cables, carry out the soldering correctly, think about multimeter tests etc....

 

[daniboun]

If @UAN uses, say, REW Generator to make his 0dBFS 16-bit 1kHz test signal, he can select to tick the "dither" option. In theory he might squeeze a -120dB noise floor from 'ideally-dithered' 16-bit with a very performant CD player as source. -125dB, though, is a real stretch/not gonna happen.

What is dither, and is it still relevant in the Hi-Res audio age?

Dither is an audio concept that, aside from producers and audio engineers, few people truly understand. We explain why it remains relevant.

www.soundguys.com

Question for you : do you own the E1DA Cosmos ADC ?

 

[S=klogW]

Thank you for these explanations. No room for chance when it comes to measuring properly ) I believe, however, that the good rules of practice also apply when assembling. Do not neglect to twist the cables, carry out the soldering correctly, think about multimeter tests etc....

With a number of ASR readers lining up to build their own SuperComputer SuperAmplifier, might you provide a detailed photo-documentary of a best practice build, please @daniboun ? I'm sure this will be of help to encourage more ASR-makers in the future.

 

[S=klogW]

Question for you : do you own the E1DA Cosmos ADC ?

Indeed I do! I was all set to sell a kidney to buy an Audio Precision solution, when, out of the blue, Ivan Khlyupin announced his intention to sell this little beauty!
I thank Ivan for a) Democratizing audio test & measurement and b) saving me from my (very impulsive) self!

 

[daniboun]

With a number of ASR readers lining up to build their own SuperComputer SuperAmplifier, might you provide a detailed photo-documentary of a best practice build, please @daniboun ? I'm sure this will be of help to encourage more ASR-makers in the future.

there are probably some great tutorials available on the web) I remain a modest little Diyer)
In any case, if I can give one piece of advice to everyone: patience is the mother of all virtues)

I can share some photos of my previous projects) from TPA325X / Purifi / Hypex Ncore / Infineon etc

And many others )

 

[somebodyelse]

A balanced interface normally has three wires:

1. Reference (usually ground)
2. Signal (hot)
3. Inverse (cold)

As you can see, you left a cable disconnected (ground)

View attachment 311451

Not exactly. Go to https://www.hypex.nl/support/downloads/ and read 'The G Word" for an explanation. Or any other good resource explaining Pin 1 Problems for that matter - AN007 at Jensen Transformers for example.