Dear Guys,
delayed too long for BA-3 adjust because busy work, and luckily today i got time to make Trimer box and start exploring BA-3 distortion.
i would like to thanks to all of you for great support. attached is what i got today. Does it look good?
I can adjust for minimum THD or K2 > K3, but can not make K3 > K2, is that normal?
Next i will do listening test each P3 position, that would be very interesting, thanks again.
delayed too long for BA-3 adjust because busy work, and luckily today i got time to make Trimer box and start exploring BA-3 distortion.
i would like to thanks to all of you for great support. attached is what i got today. Does it look good?
I can adjust for minimum THD or K2 > K3, but can not make K3 > K2, is that normal?
Next i will do listening test each P3 position, that would be very interesting, thanks again.
I've no idea what wrong now.
I reduce R6/R7 to 50Ohm ( 100R//100R) to reduce gain, R13 let 330Ohm as normal. i do not have 2sk2013/2sj313 so replace it with IRF610/IRF9610. will it cause something wrong?
I run at +-28VDC too.
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Reducing R6/7 gives for the IRFs too low biasing voltage.
Toshibas around 1V5, IRFs around 4V.
As far as I remember you have to increase even the pots to 1K5 to get the voltage needed over them.
Let the 100R in place or make them even bigger!
Is there 1V over the 22R at the IRFs. I don't thinks so... Please check this.
Reducing the gain is done with R13.
Toshibas around 1V5, IRFs around 4V.
As far as I remember you have to increase even the pots to 1K5 to get the voltage needed over them.
Let the 100R in place or make them even bigger!
Is there 1V over the 22R at the IRFs. I don't thinks so... Please check this.
Reducing the gain is done with R13.
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Thanks generg,
i used the pot 1K, and bias 1V over 22R. can you recommend some bias V for IRF610/9610?
Thanks.
Thanks generg,
I already used 1K pot, and there is no problem to get 1V on 22R. i even can bias as higher.
after adjust for minimal distortion, i can get THD~0.015%. Is it good enough?
So I was wrong, sorry.
Meanwhile I remember that I used one time IRFs just for fun and I was astonished about the fairly higher distortion.
Please tell me, what voltage is on the output when you look at your distortion, 5V?
How do manage to get now this low distortion? And no more K2 or k3?
And did you correct the offset and the bias values after each change at P3.
P3 changes influence P1 and P2.
Meanwhile I remember that I used one time IRFs just for fun and I was astonished about the fairly higher distortion.
Please tell me, what voltage is on the output when you look at your distortion, 5V?
How do manage to get now this low distortion? And no more K2 or k3?
And did you correct the offset and the bias values after each change at P3.
P3 changes influence P1 and P2.
