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gkelm
05-21-2005, 12:13 PM
Hey guys...just acquired this amp, nice and clean. Could use some advice on a couple things...apologies in advance for the newbie/dummy questions in the tech section!

1) The previous owner changed out the electrolytic can caps, and was cool enough to include the old parts. These are the old ones:
http://tinypic.com/5arg36

New ones:
http://tinypic.com/5arl1i

I noticed the new ones look shorter, but appear to have the correct value...do these caps make a tonal difference?

2) The amp came without tubes...but he said he had it biased at around 365 volts, and recommended new tubes and rebiasing. Just got it yesterday and couldn't wait to try it, so I dropped in a pair of Chinese el34s I had laying around...taking it easy on the volume, but sounds great so far.

My question concerns biasing...I had planned to have this done (a local tech does biasing for free with purchase of tubes). How critical is biasing in such a case? I've freely swapped tubes before without having them biased (i.e., Masnoette 6V6s--EH out and JJ in). Insights?

Thanks.
Greg

wilder
05-22-2005, 02:03 PM
Greg,

You should probably get it biased. However, if it sounds loud and clean up to about 5 on the volume then you're probably pretty close. If you have a DVM I can show you how to bias it. The new caps are F&Ts...they are the best readily available replacements for the original Daly's.

Chris

gkelm
05-23-2005, 07:25 AM
Thanks Chris-
It starts to crunch a fair amout earlier than that. DVM = digital volt meter? I have one of those. :)
Greg

wilder
05-23-2005, 10:51 AM
If it's breaking up early, then it's likely running a little hot. Those tubes probably won't last long, but I didn't get the impression they were valued anyway. DVM= Digital Volt Meter.

Chris