One tube reverb question??

[ukulele]

Hi,

This is my first post here. I just finished Hybrid-A with one tube reverb but made a mistake that I kind a like. In the reverb section I put 100k trimmer resistor in place of 100k resistor.

I just wondered if there is any harm if I leave it like it is.

The schematic is attached

Thanks, Mikael

[Darkbluemurder]

There is probably no harm done other than you may have no reverb when the trimmer is set to zero ohms.

[heisthl]

If you wired the transformer phase neutral you should get feedback from recyling the reverb output back to the reverb input.

[ukulele]

Thanks for your answers.

When I turn the reverb pot to all the way down I don't get any signal, so it acts as some kind of master volume but without adding any more volume, only more reverb.

But the reason I like it is because the sound becomes a little bit fuller with the trimmer resistor. I have tried 100k resistor too.



Heisthl, I don't get unusual feedback

[heisthl]

If the schematic is correctly indicating what you have you must have the transformer wired so it is putting the signal out of phase or you would have regenerating feedback. You need to swap the wires on the output(or input) side of the transformer to get the "full range" reverb tone. Right now you are only getting the "out of phase" reverb sound which should be considerably thinner. Generally the input side is red/blue with red going to b+ and blue going to the tube. The output side is usually green(or brown)/black with black going to ground. Of course not all transformers are wound/color coded alike. The last build I did had the transformer purposely backward because it had 2 recovery stages.

[klingo]

hi

are you using ecc832/12dw7 in order to feed transformer with 12au7/ecc82 section?

or is it working good with 12ax7?

[ukulele]

Heisthl, I think that I had the transformer wired so that it was putting the signal out of phase. I had red in B+ and blue in tube but in my transformer it should be another way around so I rewired it and took the trimmer of and put 100k there and now it is working like it should. I'm using 12ax7 reverb tube.

Thanks for your help!

[heisthl]

The big question is "Does it sound better?"

[ukulele]

Well at least different. Sound is much clearer now which is a good thing. But maybe the best sound is without the reverb. Maybe I have to build a d-lator.

[heisthl]

I'm working on a different design for the one tube reverb that may not be a "tone killer" I'll let you know after I've tested it (see Champ Conversion - schematic in the files section).