Say we instead have a current source at the bottom.
And only the transistor at top delivering AC.
Would a cap be more desirable then?
And only the transistor at top delivering AC.
Would a cap be more desirable then?
This is my experience with the subject.
I used a 47uF electrolytic cap (of good quality) parallel to the (typical) bias circuit in a class-b amplifier I 'm building and the result was very bad (distortion in mid-hi freq).
I changed to a (large) film cap but with no improvement.
I used an electrolytic bypassed with a small film and it was better.
When I used just a small film cap 0.33 uF it sounded great.
Now I'm trying to explain it. Any ideas.
I used a 47uF electrolytic cap (of good quality) parallel to the (typical) bias circuit in a class-b amplifier I 'm building and the result was very bad (distortion in mid-hi freq).
I changed to a (large) film cap but with no improvement.
I used an electrolytic bypassed with a small film and it was better.
When I used just a small film cap 0.33 uF it sounded great.
Now I'm trying to explain it. Any ideas.
Hi,
I hate to disagree with the Master😱 , but changing the Vbe multiplier bypass cap makes a considerable difference to the overall sound of power amps, or at least to several amps which I have tinkered with. I am not talking 'chalk & cheese' here, of course, but all of these differences which are significant, do add up and give rise to a much more enjoyable overall sound.
As someone else has pointed out, this is to a lesser extent than say an input coupling cap (or my pet hate, the feedback DC blocking cap), but don't make the mistake of assuming any old cap will do here!
Just try the difference between say a poor electrolytic and a very good quality plastic film (of similar values, in case you think this skews the results!) and see what this does.
The same goes for the cap and resistor in any output Zobel, too!
Regards,
I hate to disagree with the Master😱 , but changing the Vbe multiplier bypass cap makes a considerable difference to the overall sound of power amps, or at least to several amps which I have tinkered with. I am not talking 'chalk & cheese' here, of course, but all of these differences which are significant, do add up and give rise to a much more enjoyable overall sound.
As someone else has pointed out, this is to a lesser extent than say an input coupling cap (or my pet hate, the feedback DC blocking cap), but don't make the mistake of assuming any old cap will do here!
Just try the difference between say a poor electrolytic and a very good quality plastic film (of similar values, in case you think this skews the results!) and see what this does.
The same goes for the cap and resistor in any output Zobel, too!
Regards,
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