I miss the days when my PCBs were single layer, and I could make them myself... (HCl + H2O2)
But now they are too small to make them single layer...
But now they are too small to make them single layer...
We still need to work on the scheme. ugly so far.
It is better not to put overload protection in the model.
It is better not to put overload protection in the model.
New feedback arrangement: R3/R4/R5 ??
Also - R12 ? Something is not really symmetrical?
Also - R12 ? Something is not really symmetrical?
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I kept the feedback the same as before, and the sim results are very good.
Didn't check square waves yet...
The idea would be to make it as good as the latest non-symmetrical version, AND much faster.
Didn't check square waves yet...
The idea would be to make it as good as the latest non-symmetrical version, AND much faster.
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I now it. But wasn't any better than non-symmetrical.
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Я вот это. Но не лучше, чем несимметричный.
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Я вот это. Но не лучше, чем несимметричный.
Hi, Guys!

The layout worked all night and nothing happened.

The offset has not changed, 1mv at the output. I connected SONY SACD Player music, good AudioTechnica headphones. I didn't like the sound at all, the onlymusic 2.5 (Linn Topology) amplifier connected to the second channel sounded more assertive. After numerous experiments that I did all day, I stopped at OPAMP LME49710 (TI) and made a small adjustment to your scheme. The Earth must be bred by a star, otherwise the excitation at a high frequency is inevitable. The zener diodes were initially replaced with TL1431 modules, and the LEDs were shunted with capacitors. Transistors were also replaced. The sound has changed dramatically for the better. Tomorrow I will continue my experiments and compare them with the CFA amplifier.




The layout worked all night and nothing happened.

The offset has not changed, 1mv at the output. I connected SONY SACD Player music, good AudioTechnica headphones. I didn't like the sound at all, the onlymusic 2.5 (Linn Topology) amplifier connected to the second channel sounded more assertive. After numerous experiments that I did all day, I stopped at OPAMP LME49710 (TI) and made a small adjustment to your scheme. The Earth must be bred by a star, otherwise the excitation at a high frequency is inevitable. The zener diodes were initially replaced with TL1431 modules, and the LEDs were shunted with capacitors. Transistors were also replaced. The sound has changed dramatically for the better. Tomorrow I will continue my experiments and compare them with the CFA amplifier.



Grounds on your 'corrected' schematic is correct.
All, except input, are connected to PGND.
As for op-amps - I always use TL071 in the sim, and then test with other op-amps
when built. Never could tell the difference, so I usually leave TL071 in.
As for question 'which amps sounds better' - I have 12 amps on my rack right now.
I rotate them every few weeks. After 1 week of listening, I always have a feeling it doesn't sound right, and when I replace it with another one - I always think - this new amp sounds better. And that's how the story repeats itself every few weeks.
After listening to to so many amps, I really can't tell which one I like the most...
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Основание на вашей «исправленной» схеме правильное. Все, кроме входа, подключены к PGND. Что касается операционных усилителей - я всегда использую TL071 в симке, а затем тестирую с другими операционными усилителями когда построен. Никогда не видел разницы, поэтому я обычно оставляю TL071 внутри. Что касается вопроса «какие усилители звучат лучше» - у меня сейчас на стойке 12 усилители. Я меняю их каждые несколько недель. После недели прослушивания у меня всегда возникает ощущение, что он звучит неправильно, и когда я заменяю его другим - я всегда думаю - этот усилитель лучше.
И вот так история повторяется каждые несколько недель.Послушав столько усилителей, я действительно не могу сказать, какой из них мне нравится больше всего ...
All, except input, are connected to PGND.
As for op-amps - I always use TL071 in the sim, and then test with other op-amps
when built. Never could tell the difference, so I usually leave TL071 in.
As for question 'which amps sounds better' - I have 12 amps on my rack right now.
I rotate them every few weeks. After 1 week of listening, I always have a feeling it doesn't sound right, and when I replace it with another one - I always think - this new amp sounds better. And that's how the story repeats itself every few weeks.
After listening to to so many amps, I really can't tell which one I like the most...
=============
Основание на вашей «исправленной» схеме правильное. Все, кроме входа, подключены к PGND. Что касается операционных усилителей - я всегда использую TL071 в симке, а затем тестирую с другими операционными усилителями когда построен. Никогда не видел разницы, поэтому я обычно оставляю TL071 внутри. Что касается вопроса «какие усилители звучат лучше» - у меня сейчас на стойке 12 усилители. Я меняю их каждые несколько недель. После недели прослушивания у меня всегда возникает ощущение, что он звучит неправильно, и когда я заменяю его другим - я всегда думаю - этот усилитель лучше.
И вот так история повторяется каждые несколько недель.Послушав столько усилителей, я действительно не могу сказать, какой из них мне нравится больше всего ...
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Yes, good bass...
C7 is not a 'usual' feedback cap that normally is greater than 100uF electrolytic (the bigger the better).
This is a compensation cap to make it more stable.
Diodes in parallel are for clip-protection.
I don't have an idea if it affects bass response, but I would be surprised..
Maxim, can you correct me?
I think original 200pF value should be kept.
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C7 - это не «обычный» конденсатор с обратной связью, который обычно электролитический greater than 100 мкФ (чем больше, тем лучше). Это компенсационный колпачок для большей устойчивости. Параллельно подключенные диоды предназначены для защиты от зажима. Я понятия не имею, влияет ли это на низкие частоты, но я был бы удивлен .. Максим, ты можешь меня поправить? Я считаю, что следует сохранить исходное значение 200 пФ.
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C7 Reduces the frequency of a single gain with a broken oos Fed. Eliminates excitation, but reduces the rate of rise of the output voltage.The RRCRC correction values are interrelated.
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C7 уменьшает частоту одиночного усиления при сломанном питании ООС. Устраняет возбуждение, но снижает скорость нарастания выходного напряжения.Значения коррекции RRCRC взаимосвязаны.
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C7 уменьшает частоту одиночного усиления при сломанном питании ООС. Устраняет возбуждение, но снижает скорость нарастания выходного напряжения.Значения коррекции RRCRC взаимосвязаны.
Taste and color... But CFA is closer to my heart. But the torment is greater.
These are amplifiers of different levels.
C7 in the limiter 2200mk? yes well.can not be
2200uF - wrong caliber!
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Да гранаты у него не той системы 🙂
I was just investigating cascode modification (Hawksford cascode).
See
My folded-cascode VAS linearity investigation
Example below is just an illustration, when I modified cascode, all results improved. Doesn't matter - symmetrical or not, it might be worth trying it..
See
My folded-cascode VAS linearity investigation
Example below is just an illustration, when I modified cascode, all results improved. Doesn't matter - symmetrical or not, it might be worth trying it..
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