The manual is available at www.adcom.com, and Sean guessed right. If you heard a difference (while not using a turntable), it may have been due to something else you inadvertantly changed (unplugging and re-plugging in a cable, etc.). Try listening with the switch in different positions again.
Capacitance ?
I am currently using a vintage Adcom 555 pre-amp in a simple stereo set-up. On the rear of the pre there is a switch with three settings : Capacitance
55 pf
175 pf
235 pf
What are these settings for? Yesterday I set the switch to 235 pf from 55 pf where it had been set for almost a year unnoticed. And, it may be my imagination...as it sometimes is with the 'audio' senses , but it really seemed as if the sound opened up a bit when I moved that switch to the 235 pf position. Somebody please help me understand.
55 pf
175 pf
235 pf
What are these settings for? Yesterday I set the switch to 235 pf from 55 pf where it had been set for almost a year unnoticed. And, it may be my imagination...as it sometimes is with the 'audio' senses , but it really seemed as if the sound opened up a bit when I moved that switch to the 235 pf position. Somebody please help me understand.