ampage
Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. The sunn still shines online!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

LOOKING FOR SCHEMATIC


 :
8/11/1999 10:48 PM
Trace
LOOKING FOR SCHEMATIC
Hey all;  
 
 
 
I'm in serach of a Peavey Classic 50 schematic. I have one coming in where the shafts of the Volume & Treble pots are broken off.  
 
 
 
I'd like to take a look at the shcematic since the owner wants it modded and I also need the values to the pots. I assume the Volume is most likely 1Meg and Treble is in and around 250K or so.  
 
 
 
Any help would be greatly appreciated! I wanted to grab the pots before I opened her up.  
 
 
 
Thanks so much gang!  
 
Trace
 
8/11/1999 11:42 PM
kg
Trace, keep in mind peavey is fond of using the "mini" pots in places, or perhaps some with standoffs. The value may be easy--an exact enough replacement so that you don't waste 10 hours tring to make it work may be harder!  
 
 
 
I'd borrow the amp from the guy and take a look-see. Measure the value of the pots and see if there's anything special about them. I'd wager they aren't your average Alpha pot!  
 
 
 
FWIW,  
 
Ken
 
8/12/1999 12:40 AM
Ed

Trace-  
 
I have a copy that I'll copy & send no charge. Email your address. Peavey will sell them to you for $2.50, minimum order is $5.00 - just get another one while you're at it if you want.  
 
 
 
Have you noticed that you have to take the amp entirely apart, just to get to those pots? Now, wasn't that fun? While you're in there, I'd suggest replacing the input jacks with Switchcraft #11's - you know that all too common mishap of guitar cord yank. Even though, by changing to the metal jacks will connect input ground to chassis ground & give the amp some extra noise, it's only negligiable. And it sure beats having to take the whole bleedin' amp completely apart just to change those plastic input jacks.  
 
 
 
Hope it works - those amps are on my shitbox list  
 
Ed
 
8/12/1999 3:38 AM
Trace

KG & Ed;  
 
 
 
Man!!!! This thing is NOT EASY to work on!! You DO have to take the entire thing apart just to get to the pots! The pots have the two extra legs on the rear of the pots. This is a new one on me. Where do get these babies??  
 
 
 
This amp is built like a tinker toy with some mighty silly stuff in the circuit. As far as I can by looking at it almost every plate cap is a .047uF and every cap on the preamp section (but one) is 22uF. Talk about A LOT of bass! (ha, ha) All the plate resistors except for the phase inverter are 150K...."buzzy" and very "Chain saw" like.  
 
 
 
This thing sounds mighty dark...is this common for this amp guys? It's already noisy and the input jacks are pretty crappy indeed.  
 
 
 
Well, I guess modding it would probably be in this things best interest (ha, ha) Does anyone know what kind of speakers are in this?  
 
 
 
Thanks guys!!!  
 
Trace  
 
PS: If anyone is a certified Peavey repair guy could you email me?
 
8/12/1999 5:14 AM
Brandon

Trace,  
 
 
 
Check out Steve Aloha's Blue Guitar Site. He has extensive mods listed for the Classic 30 and Classic 50.  
 
 
 
Brandon
 
8/12/1999 6:27 AM
Steve A.

Trace:  
 
 
 
    The schematics and mods are on my site. After taking mine apart about 25 times I have it down to a science: it takes about 15 minutes to pull the boards and another 15 minutes to put it all back together...  
 
 
 
    For my "Tweed Bassman Mod" (actually more like a Plexi) I replaced the 10k post-gain pot (think about that one!) with one of those 7/8" diameter pots that come on cheap imported guitars (500K). By soldering the 3 lugs directly to the pcb (add a small piece of wire to strengthen the joint) and reaming out the hole in the metal a bit, everything lined up pretty good. I used a 1/4" chicken head knob I had around which will fool anybody (as long as they don't look too closely).  
 
 
 
    But you might just want to order the pots from Peavey...  
 
 
 
Steve Ahola  
 
 
 
P.S. If you think that the Classic 50 is a built like a tinker toy you obviously haven't taken apart a Classic 30...
 
8/12/1999 1:25 PM
Trace

Steve;  
 
 
 
Thanks! That's very cool of you to post all those schematics.  
 
 
 
quote:
"I have it down to a science: it takes about 15 minutes to pull the boards and another 15 minutes to put it all back together..."
 
 
 
 
Yes indeed Steve! I had a problem taking the screws out of the left hand side of the PCB for the preamp tubes. They were pretty froze and on an angel which made it worse yet.  
 
 
 
quote:
"If you think that the Classic 50 is a built like a tinker toy you obviously haven't taken apart a Classic 30..."
 
 
 
 
Oh lord, you mean it gets worse?? Man oh man this company needs to re-think their amps in my opinion. This thing was terrible sounding right out of the box and good tubes made no difference what so ever!  
 
 
 
Steve, did you figure out a way to cut down on the "hiss" in this model?? There sure seems to be a lot of "hissing" going on.  
 
 
 
Even using the solder-braid the traces are pretty weak and cheesy. It's truly remarkable what some people do just to save a few pennies in the manufacturing cost of an amp.  
 
 
 
I pretty much changed everything on the first two preamp tubes and some on the PI tube. I also changed some of the caps as well. I want to get a regular copy so I can make the changes on the schematic and share it those who want it.  
 
 
 
Thanks Steve;  
 
Trace  
 
 
 
 

  Page 1 of 4 Next> Last Page>>