Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: ACDCG400 on February 17, 2012, 02:03:40 am

Title: Question on 1 tube reverb
Post by: ACDCG400 on February 17, 2012, 02:03:40 am

Quick question guys: I gutted a twin reverb reissue and put in a 2 channel (original clean/distortion) circuit.  The channels mix together with 2 220k resistors into a 100k before the cap to the entrance of the PI. Ive tried to implement a 1 tube reverb, but to no avail, any thoughts on how it can be done? I think I missed something stupid. Anyone have a quick layout lying around? Thanks!

Title: Re: Question on 1 tube reverb
Post by: kagliostro on February 17, 2012, 05:40:13 am

Look to the schematic of the Vox Berkely II Super Reverb

http://www.el34world.com/charts/Schematics/files/Vox/Vox_BERKELY_II_SUPER_REVERB_V-8.pdf (http://www.el34world.com/charts/Schematics/files/Vox/Vox_BERKELY_II_SUPER_REVERB_V-8.pdf)

all the "job" is around R14, the 3.3M resistor and C8 the 10uuf capacitor

Ciao

Kagliostro

Title: Re: Question on 1 tube reverb
Post by: tubenit on February 17, 2012, 07:56:51 am

Did you look in the ARCHIVES at the "one tube reverb" thread?

http://www.el34world.com/Forum/index.php?topic=7957.0 (http://www.el34world.com/Forum/index.php?topic=7957.0)

With respect, Tubenit

Title: Re: Question on 1 tube reverb
Post by: ACDCG400 on February 18, 2012, 03:17:12 am

Tubenit: I did! I actually have it bookmarked! haha. I think I made the circuit right but something small is awry. Do the reverb jacks on the amp need to be insulated?

kagliostro: checking it out right now! Thanks!

Title: Re: Question on 1 tube reverb
Post by: tubenit on February 18, 2012, 07:09:55 am

What is it doing or not doing?   Can you hit the reverb tank & hear a splash?

Is the tank a known good tank?   Do you have good send/return wires hooked correctly?
Are you using known good tubes?   What are the voltages like on the reverb tube?

Can you show how you have the reverb jacks hooked up?  Can you post a picture?

Some specific information would be helpful in trying to help you.

With respect, Tubenit

Title: Re: Question on 1 tube reverb
Post by: ACDCG400 on February 18, 2012, 01:15:02 pm

I'm getting no reverb at all, but the tank splashes when shook. Tank is definitely good, i ended up buying a MOD one just to rule it out and no dice. Ive used multiple sets of rca cabling from different sources -_- and definitely good tubes. voltages were: pin 1: 300v pin 3: 1.6v pin 6: 170v and pin 8: 1.3v. Ill definitely draw a picture! I gave the amp back to my friend since he needed it for a gig, so ill have it back soon.