Someone hacked up my Vox...need some advice.

10/16/2004 8:54 AM

Nick

Someone hacked up my Vox...need some advice. (This is a cross post from general discussion)     I have an old '64 Vox AC-50 head. I've owned it for a few years, and it's always been one of, if not the best sounding head i've ever heard. I love this amp dearly.     But a few months back, I lent it to a buddy of mine. He knocked it off the top of a 4x12, and it got banged up pretty bad when a concrete floor ended its journey.     The chassis got bent pretty good, and whatever electrical problems it had were a bit over my head. I decided to send it out to a pretty reputable tech in the midwest.     To make a long story short, he did a FANTASTIC job fixing it. He bent the chassis back and relaquered it...really cleaned the whole amp up and rewired the entire thing.     One slight problem. When I got the amp back, I didn't have a '64 AC-50 anymore. He replaced EVERY SINGLE component in the pre-amp, and most of the components in the bias and output sections. 95% of the components are new.     I now have a clone of a '64 Vox AC-50. Needless to say, the amp sounds a bit different than it did before.     I have all the original components, as he sent them back to me in a bag.     I have a few questions...     I obviously want to put the essentials back in, like the Mustard caps. But i'm wondering where I should draw the line, and what components will get my head sounding the way it did before. Should I worry about things like pre-tube cathode resistors or plate resistors?     Secondly...     I obviously have no way of knowing which part went where. For instance...I've got 7 100K resistors. Some of them are plate resistors. Some of them are slope resistors in the tone stacks. Some are drifted up a bit (112K, 114K)...If I put the drifted ones in the wrong place, it's a moot point putting them back in the amp. I'm assuming the plate R's are the ones that are drifted up. But i'm wondering if I can figure things out by trends that components have historically. Do plate R's drift up usually? Do slope R's usually stay stable?       Sorry to write a novel on this...but i'm just wondering if you guys (who largely have much more experience than I ), can point me in the right direction as to what I should worry about putting back in the head to get it sounding like it did...and if you have any tips on trying to figure out which components (of the same value) went where.     He's replaced all the caps with Sprague 716P's BTW. Resistors seem to be 1W carbon comps, newer style ones.     Thanks in advance for dealing with my longwindedness.     -Nick