simple mic pre with single ended 6SN7 gain stage, (B+300v, Ra15k, Rk 750r, 4uf output cap to 4:1 output transformer sounding just fine
about 1% distortion... way less on normal usage.
no noise problem, no hum, all good.
if i replace 4:1 with 2:1 out trx, i am getting way less distortion, more gain, but noticeably more hum 50hz...
its almost audible on high volume.
if i add additional white cathode follower to reduce output impedance and still same 2:1 out trx,
all that extra hum goes away!
any idea why, i have more hum, with 2:1 trx and WCF is taking it away!
is impedance mismatch causing this extra hum ?
about 1% distortion... way less on normal usage.
no noise problem, no hum, all good.
if i replace 4:1 with 2:1 out trx, i am getting way less distortion, more gain, but noticeably more hum 50hz...
its almost audible on high volume.
if i add additional white cathode follower to reduce output impedance and still same 2:1 out trx,
all that extra hum goes away!
any idea why, i have more hum, with 2:1 trx and WCF is taking it away!
is impedance mismatch causing this extra hum ?