It is currently Mon Mar 16, 2020 4:51 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 9 posts ] 
Author Message
Post subject: '76 silverface twin reverb, reverb doesn't work!
Posted: Tue Aug 10, 2010 1:38 pm
Offline
Hobbyist
Hobbyist

Joined: Tue Aug 10, 2010 1:29 pm
Posts: 25
Recently I bought my first vintage amp, a silverface fender twin reverb from '76. Sounds beautiful, and all the tubes light up. even plugged a shorted jack into the little vibrato plug so the vibro works too!
However, the reverb does not work and I like the reverb sound in these amps. i fiddled with the tank, and with the verb cranked to 10 i can knock on the tank and get a crashing sound, like a healthy tank. But when i play, I can't get that echoey goodness at all. I think its the tank, because i plugged it into my blues jr's tank and it sounded fine (very small, but i could hear reverb).
The tank is probably shot. Is there any way I could repair it, or should I just pay for a new one?

Thanks,
Chris


Top
Profile
Fender Play Winter Sale 2020
Post subject:
Posted: Tue Aug 10, 2010 2:38 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26417
Location: Tombstone Territory
Try connecting the TR's tank to your Blues Jr. and note the result. If you have reverb then, I'd check the reverb input cable in your TR for continuity.

HTH

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject:
Posted: Tue Aug 10, 2010 3:53 pm
Offline
Hobbyist
Hobbyist

Joined: Tue Aug 10, 2010 1:29 pm
Posts: 25
Retroverbial wrote:
Try connecting the TR's tank to your Blues Jr. and note the result. If you have reverb then, I'd check the reverb input cable in your TR for continuity.

HTH

Arjay


when i hooked it up, it sounded small, probably because the jr tank is about half the size not a problem with the line, i tried it with a brand new monstercable as well with the same results. I opened the tank the other day and couldn't find any loose wires or anything. any idea what i sould even be looking for?


Top
Profile
Post subject:
Posted: Tue Aug 10, 2010 4:24 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Wed Mar 31, 2010 12:48 am
Posts: 26417
Location: Tombstone Territory
Check the continuity of the reverb tank itself, using a DVM. You will not see a "dead short" if the tank is okay as the unit does offer some resistance when operating correctly.

There are small transducers (basically, small transformers) connected mechanically to each end of both spring sets via some very fragile wires inside the unit itself. These wires can often vibrate loose due to age. Some folks report success in repairing these but they're pretty cantankerous to work with. If a continuity check shows the tank as "open", you'll need to repair or replace it.

If your DVM shows the tank as good it's possible that corrosion on the tank's jacks or those at the rear of the amp chassis itself are preventing a solid connection. If so, clean these thoroughly with contact cleaner.

Be sure the amp is switched off and unplugged before proceeding with any diagnostic checks and/or servicing.

HTH

Arjay

_________________
"Here's why reliability is job one: A great sounding amp that breaks down goes from being a favorite piece of gear to a useless piece of crap in less time than it takes to read this sentence." -- BRUCE ZINKY


Top
Profile
Post subject:
Posted: Wed Aug 11, 2010 6:51 am
Offline
Aspiring Musician
Aspiring Musician

Joined: Fri Dec 12, 2008 5:32 pm
Posts: 329
swap the 12at7 see if you get reverb that way


Top
Profile
Post subject:
Posted: Tue Oct 12, 2010 3:11 pm
Offline
Hobbyist
Hobbyist

Joined: Tue Aug 10, 2010 1:29 pm
Posts: 25
alright. today i threw in an accutronics type 4. there is definantly reverb, but its relatively small. at 10, the verb sounds like the blues jr at 5. any thoughts? should i have gone with the type 9?


Top
Profile
Post subject:
Posted: Tue Oct 12, 2010 5:46 pm
Offline
Professional Musician
Professional Musician

Joined: Fri Jun 26, 2009 6:53 pm
Posts: 2252
Location: Harvard IL
The 4AB3C1B tank should work fine in your amp. Have you tried a fresh 12AT7 in the V3 and 12AX7 in the V4 slots ? Art

_________________
None of Us are free, if One of Us is chained !


Top
Profile
Post subject:
Posted: Tue Oct 12, 2010 7:02 pm
Offline
Hobbyist
Hobbyist
User avatar

Joined: Mon Feb 11, 2008 3:37 pm
Posts: 81
My first guess would be the reverb send tube is weak, try replacing it. Second guess is a bad connection between the amp and tank. Get a VOM and test the leads to and from the tank to the amp. Also test the tank for a open circuit. If the tank is good you should get a resistance reading on each side of the tank.


Top
Profile
Post subject:
Posted: Thu Oct 14, 2010 8:39 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
It's append sometimes to me and it was dirty and/or rusted RCA connectors at the back of the amp, reverb in and reverb out .
Try to clean them or jump them to test your reverb tank.


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 9 posts ] 

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: