Hello all,
I just finished assembling my smash and it is amazing... for the first hour there was no microphony and it sounded really gdI then as the tube started heating up, there is now a 50hz hum on both channels and severe microphony... it is like feedback sound that increases on volume then goes away and comes back. It is very terrible and annoying.all voltages and resistance are gd.
The smash is isolated well from vibations and is still very microphonic. My system consist of a 3 stage pp 6l6 amp with enough gain for a preamp not to be use but i still have a lot of usable range with the volume pot. My speakers are kef ls50 with an 85db sensitivity.
I have the same problem like the one of our fellow member and have read the thread... i really dnt want to put an inline attenuator as i think its a bandaid for the problem...
Pls help..... I dnt know what to do anymore.... I really like the preamp, but I won't be able use it if the problem persist... its my first kit from bottleahead. I wished bottlehead did more to.prevent stuff like this from happening.
Pls help as the wifey will be upset if I dnt.fix the problem... as she is excited to paint the wood chassis.....
Thank you
