That's exactly the point: you can't possibly say whether it's a good or a bad design if you don't know what it is meant for. Apparently it is for some sort of headphone amplifier; if it is an exotic kind of headphone amplifier with constant supply current, poor PSRR and very high SNR target, then this may be a sensible solution. On the other hand, if it's an amplifier with signal-dependent supply current and very poor PSRR, then this supply could dominate the distortion. If it's a headphone amplifier with very good PSRR, then it doesn't matter at all.
Then I agree with peufeu. Op-amp circuits usually have good PSRR, at least at low frequencies, and their class-AB output stages draw distorted currents from their supplies. Hence, the capacitance multiplier will probably have no measurable effect on the circuit's performance, but if it does, it will probably just increase distortion.
the typical cheaper 3pin regulators have quite poor high frequency performance.
They will give a better output if you don't feed lots of high frequency interference into them.
The better location for enhanced interference suppression is BEFORE the 3pin regulator.
You can start this by using an IEC socket with the steel canned interference filter integrated inside.
Then you use a transformer that has close coupled input and output wiring.
Then you use effective filtering after the rectifier.
Some may want to add in a secondary winding snubber to avoid the potential for ringing of the supply when presented with step changes in current demand.
All of this is before the 3pin regulator.
place the 3pin regulator as close to the load as possible.
Run the wiring to that regulator as a clsoe coupled pair to minimise emi from the cable.
They will give a better output if you don't feed lots of high frequency interference into them.
The better location for enhanced interference suppression is BEFORE the 3pin regulator.
You can start this by using an IEC socket with the steel canned interference filter integrated inside.
Then you use a transformer that has close coupled input and output wiring.
Then you use effective filtering after the rectifier.
Some may want to add in a secondary winding snubber to avoid the potential for ringing of the supply when presented with step changes in current demand.
All of this is before the 3pin regulator.
place the 3pin regulator as close to the load as possible.
Run the wiring to that regulator as a clsoe coupled pair to minimise emi from the cable.
http://www.audio-perfection.com/forum/showthread.php?tid=263
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See and read here. But in Russian.
Very interesting about LM337, LM317 .
Try to use Google translater.
.
.
See and read here. But in Russian.
Very interesting about LM337, LM317 .
Try to use Google translater.
.
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