adding dwell, tone etc to standard amp reverb. doable?

[jp-90]

I love spring reverb and particularly like units with more unique (some would say trashy) spring sounds and more control. Thanks to some other forum members, I just got the reverb up and running on a Traynor YGL 3, and it got me wondering if it was easily doable to add other controls to your typical, tube-driven on-board amp reverb. Thoughts?

I love how the fender units (as well as others--i have a soleMate unit that is great) allow for dwell and tone tweaking in addition to mix. I also like the interesting take on reverb that comes with the Sunn beta lead, a reverb setup that allows you to entirely mix OUT the clean signal so that you're only hearing what's passing through the reverb pan--this creates some cool effects. Would it be possible to add, say, a small box in line with the reverb drive signal to tweak some of or all of these parameters?

THANKS.

[stokes]

I had seen a mod for some Fender amps to add a dwell control,dont remember where or exactly what it entails.It was for tube reverb,not sure what is in the Traynor,tube or solid state,but it should be doable,just look at the schem on the Fender 6G15 and try to replicats it in your Traynor.If I can remember where I saw the mod for the Fender amp,I will get back to you.I have a feeling it may have been a Gerald Weber thing.

[tboy]

Fender reverb amps have a 1m grid resistor on the 12AT7 driver tube. If you replace that with a pot (wired like a volume control), you'll have a "dwell" control. Another name for it would be "reverb drive level."

[d95err]

A reverb tone control probably works best after the pan, in the recovery stage. A simple guitar-style tone control should work. You'd have to experiment a bit to find a suitable pot/capacitor value.

You could also work with the amount of bass going into the reverb. Perhaps a switch to change the coupling cap going into the reverb driver.

[GibsonLover]

It works very well. I did it to a Princeton Reverb just by following the 6G15 schematic. The bass is already rolled off quite a bit on any spring reverb circuit to avoid crashing the tank. The 6G15 is no different (362Hz), that's why the tone values in the 6G15 also apply. I put the Dwell and Tone pots on the back panel. I think I tweeked the tone tone caps a little, but I can't remember why. It really does beat the snot out of a single knob reverb, and it's the best thing short of an effects loop.

[Enzo]

Here is something simple and easily restored. On a typical Fender, we use the vibrato channel and leave the dry channel alone. get a cord with an RCA to 1/4". Plug the RCA end into the OUTPUT jack on the reverb pan. Then plug the 1/4" end into the dry channel input jack. Now the dry channel becomes the reverb recovery stage, complete with tone controls.

This ought to work on any amp with separate input jacks for the two channels.

[Ronsonic]

That's one of my favorite Fender amp tricks. Gives a much sweeter and more controllable reverb sound.

[jp-90]

THANKS for the advice. The simple rca to 1/4" trick will likely be my first "mod," but i think i'll be trying for the dwell and tone knobs eventually.