Twin Reverb Help!

[Travis8]

Hi!!

I´m trying to fix my twin reverb, It´s have background noise even if the guitar and cable are disconnected and all volumes down.

I tried to replace all preamp and power amp tubes. Also to disconnect or move the reverb tank and also to plug it in different places.


It´s a background hum noise but it´s loud.

Some ideas? Thank you everyone

[tubeswell]

Filter caps (and bias supply cap(s)

[Travis8]

Filter caps (and bias supply cap(s)

Ok! I will check it under the doghouse

[Travis8]

Filter caps (and bias supply cap(s)

2x 80uf 450v
3x 22uf 500v
1x 100uf 100v

I will replace it with tad golds

[jordan86]

Helpful tips for all kinds of “background noise”

http://www.geofex.com/ampdbug/ampdebug.htm

[Latole]

1- Wicht Twin Reverb ?
2- Background noise ; hisssss, humm .....?

Vintage one ;
It may no be the issue, old amps need always new filters caps
Replace all plate resistors on 12XX7 tubes
Are 6L6's are good and matched ?
Clean all pots
Power cord with ground or not ?

Any mods on the amp ? Post picture

[Esquirefreak]

If the noise is hum, and present even when nothings plugged in - I would start by checking the breaker tips on the input jacks.

I've encountered a bad hum on a few amps that had corroded breaker tips, and therefore not making proper contact to ground. A folded piece of sandpaper and slight bending with pliers took care of the problem.

/Max

[Latole]

Right Esquirefreak,
Check the normal close contact to ground at each input  jack. Thy often need to be cleaned with burnishing tool
I, sometime, see the contacts are open, not close. Kack need repair or new one