BZLS pre-amp

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
dear all,
i have built the BZLS with original Gerber:
power supply
main
with case
supply: 60V
gain: 10dB
Before install to the case, tested with HP 8903B Audio Analyzer
sweep 20Hz ~ 50KHz,
Vin=1V
THD from 0.02% increase up to 0.08%
SNR ... about 73dB (without filter)

listening test at my friend's home ... with
CDT:Esoteric X25
Power amp: Spinx project 12

results: lack of bass! :bawling:

when tested at home with KT88 push-pull power amp, the bass is so good!! and enough!!

the transformer is with 60-0-60VAC, and i found that the heat sink for the the two FET is too hot! can't hold the finger on it!

Anyone can give me a suggest on the power supply circuit? would like to try other supply unit ...
thanks in advance! :wave2:
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.