on 5w resistors i have 1.1mV. i remove r23 and r24 should i re solder them?
edit: if i re solder them voltage drop 0.9mV
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I just measured mine and I have 8.4mV form TP1-TP2. I am running +/- 35V rails. I have all resistors installed. I think your low rails are causing some issues. If I remember correctly I soldered a 100k pot across R21 and adjusted it to find the value for R23,R24. You might try that.
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ty mr terry yes i remember you wrote it here too. but my rail voltage 28vac wich mean +/-38Vdc. and tip142 and 147 not even get warm just bd139 warming. i think my output stage cannot work cause of bias voltage is low. but i dont know how to increase it. at the bc547 base 0,5v making me think bc547 not open so tip142 and 147 cannot work. am i right?
i pull out R21 and put there 1k pot. now i can make bias but it dont stay. i make 8.4 same like you but when i cut electric and open again it start low and rising slowly. i make it work like a 10 minutes for testing and when amp getting hot distortion starting if i close volume a little bit it going away but heat rising so distortion coming back.
and i dont think this amp not close to 50w maybe 15 20. my 20w 2+1 system more louder. there is some thing i am doing wrong i think.
you think i am having problems for that bc550 i used bc547 but all is same transistors.
hi mr terry, i change 4 resistors to 2k. nothing change and there is some noise is this coming from bad ground? i cannot find that bipolars and used 2 caps. i used for mute j201 i will take it out and try too but i dont have any hope any more
(here the noise look like ground but i cannot be sure.
WhatsApp Video 2020 08 24 at 10 47 08 - YouTube
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APEXAUDIO bass guitar amp
i think this is all i can get from this amp. abouth noise i find that chase connection and one cap i dont use. i put picture for show it if any others make it.
any suggestion chase for this amp can be good. thank you
edit: is it possible if we put 1 pair more transistors with same voltage, can give more power?
thank you to mr mile for share it and mr terry thank you soo much for helping.
i think this is all i can get from this amp. abouth noise i find that chase connection and one cap i dont use. i put picture for show it if any others make it.
any suggestion chase for this amp can be good. thank you
edit: is it possible if we put 1 pair more transistors with same voltage, can give more power?
thank you to mr mile for share it and mr terry thank you soo much for helping.
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Please could someone explain if I can use the XS2 crossover posted by Mile sir for unbalanced input?
Can I just ground one of the XLR inputs?
https://www.diyaudio.com/forums/pa-systems/167363-mic-line-eq-preamps-13.html#post2294424
Can I just ground one of the XLR inputs?
https://www.diyaudio.com/forums/pa-systems/167363-mic-line-eq-preamps-13.html#post2294424
