Medium Aleph 3 8ohm@20w.

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Question ..

better feedback with

r17 100K and r21 10K with C5 10pF
or
r17 10K and r21 1K with C5 100pF ????????

can it be a good idea to change Q1 with irf9540 as in X-ccs bosoz style?
 

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I re-used irf9610 (Q5 Q6) and irf9540 (Q1), r17 100K and r21 10K with C5 10pF, also i used 1uF(polycarbonate)//C6, now the dynamic is returned and the sound is very nice but is increased the sensibility and the noise, strangely also what seems to come from the PSU. I'm thinking to reduce R8 as Nelson Pass suggested in other posts. Or will I have to replace irf9540 with irf9610? Would anyone advise me?
 
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I discovered after last changes that also increase the sensibility, but now I have 100hz 10 mVpp in over speaker out. So now I need to decrease the input sensibility. I thinks also I need to preserve input resistors ratio before XLR and rca input. Who can suggest me some advise? Thanks in advance.
 
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20db is regular gain of Aleph 3/30

that's too much for you ?

though , if you are going to decrease gain , to cure ripple on outpput ..... that's sorta just patching the problem , instead of curing it in first place

what's the real reason for excessive ripple on output ?

looking at pictures you posted up , there are several positions needing more explanation ....

for starters - give us few proper pictures from above the amp , to get full picture of things
 
20db is regular gain of Aleph 3/30

that's too much for you ?

though , if you are going to decrease gain , to cure ripple on outpput ..... that's sorta just patching the problem , instead of curing it in first place

what's the real reason for excessive ripple on output ?

looking at pictures you posted up , there are several positions needing more explanation ....

for starters - give us few proper pictures from above the amp , to get full picture of things
It is a dual mono clc filter, there are 16x22000uF of cap.
I don't believe that can be a psu problem.
Otherwise I don't need to decrease the gain but simply the input sensitivity.
 

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I just discovered that if I do not use the unbalanced input and therefore do not short (-in) signal to the gnd , the noise is reduced considerably. Obviously, this can not happen if you use unbalanced input because it reduces the input sensitivity and even the low frequencies are poor.:mad:

In any case I would like to know if the capacitors of the PSU are efficient, how can I do it?
 

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