A solid-state, FET ReVibe project

[jubal81]

I've been reading up in the Hoffman ReVibe, which is a combination of the Fender tube reverb and harmonic tremolo. Well, I've got the SurfyBear spring-pan reverb PCB on the way and fortuitously our own Midwayfair has created a brilliant little harmonic tremolo. So they just have to be paired together. It's destiny.

There are just so many variables I'm not sure the best way to do it. Floor unit, like the VanAmps SoleMate? I have a hard time picturing how that's all going to fit together in a 10" X 6" X 2" Hammond box. What about an enclosure on my amp cab and under the head with remote footswitches?

Then there's the implementation. These thing really belong between the preamp and the power amp, but I'd rather not modify my amp since it's a 'booteek' and it's brilliant. What about series & parallel? The ReVibe runs he effects in parallel, so do I need to design a mixer to marry these beauties?

Love to hear what you guys think. Here's some pictures of what's out there:

[selfdestroyer]

I got my self etched SurfyBear reverb and I have been wondering what I was going to put it in. I even looked at the mini Accutronics tanks used by some of the synth rack units and doing a pedal. I am really interested in the direction you are going with this and can't wait to see what you come up.

[midwayfair]

If you want to run the Cardinal in parallel with something, you pretty much just have to add a non-inverting buffer after the volume pot. But there are probably better implementations if it's going in an amp ... PM me if you want more specific thoughts. Mostly it involves removing the "amp simulation" aspects of the Cardinal.

[jubal81]

I got my self etched SurfyBear reverb and I have been wondering what I was going to put it in. I even looked at the mini Accutronics tanks used by some of the synth rack units and doing a pedal. I am really interested in the direction you are going with this and can't wait to see what you come up.

I've had the 9", 3-spring Accutronics tank for a few years and haven't liked any of the circuits I tried with it - none sounded nearly as good as the SurfyBear demo. I went through a lot of schematics at SS guitar and tried some of the Orange and other Opamp reverb drivers/recovery circuits and they were just too weak.

If you want to run the Cardinal in parallel with something, you pretty much just have to add a non-inverting buffer after the volume pot. But there are probably better implementations if it's going in an amp ... PM me if you want more specific thoughts. Mostly it involves removing the "amp simulation" aspects of the Cardinal.

I'm keeping the amp stock, for sure. Often tempted to monkey with it, but it's great just how it is.
I'm also definitely leaning toward the parallel option just to stay consistent with the original idea.

Guessing Input buffer to split signal (opamp a) -> Reverb -> Mixing opamp (opamp b)
                                                                      -> Cardinal -> Mixing opamp (opamp b)

I haven't given any serious thought to the circuitry or switching yet. I keep thinking the first hurdle is to figure out the setup - floor or unit under amp head.

Now in my dreams ...
(Whiddley woo, Whiddley woo, Whiddley woo)
Now that we're in the fantasy world, the reverb and tremolo are integrated and built under a big, custom pedal board with programmable switching.

[jubal81]

For inspiration. Almost convinced I need to pony up and build the tube version somehow someway.
Skip to about 2:40 for the really good stuff.

[jubal81]

Sounds just excellent, even with just the Ins/outs tied together. There's waaaay more reverb in this than I'll ever use. I also think I should get bigger heat sinks - Mosfets get REALLY hot.

[jubal81]

Also curious, would anyone be interested in a version that just uses a Belton brick?

[atreidesheir]

 

[jtn191]

Do you have a way of recording a clip? Both these are on my to do list...sometime

[GrindCustoms]

Also curious, would anyone be interested in a version that just uses a Belton brick?

Whatever you pull out, i'm in, this sounds like it's going to be the holy mother of lushness!

[jubal81]

Do you have a way of recording a clip? Both these are on my to do list...sometime

I'll try to do something with my iPhone tomorrow. Once it's done I'll find someone with a mic setup.

Whatever you pull out, i'm in, this sounds like it's going to be the holy mother of lushness!

There's a good reason this combo is a classic. It's really something special. I had them in series for a while and it sounded great, but when I tied the leads together - wow. That's what made me think a good project needs to be made - and I'd like to have one that fits in a normal pedal enclosure.

[jubal81]

Oh yeah, that's fixed now.

[jubal81]

Got the splitter/mixer going today and tweaked a bit to get it working pretty well.
Issues:
+For the reverb, there is some distortion when the dwell is pushed. Think I might try a smaller coupling cap than the 100uF.
+The recovery stage could use some more gain because as the mixer goes up, the overall volume goes down.
+ Going to switch out the Dwell & Mix pots with audio taper - needs more play in the low range.

Still can't decide on the switching. I can't see ever using the tremolo without the verb, but definitely the other way around. Did an A/B with series/parallel and haven't decided if series operation is worth a switch.

And I came up with an insanely complicated, but very cool, idea for the construction involving tinted lexan and el panels.  Shielding may be an issue ...

[jubal81]

Soliciting suggestions for getting more gain from this stage:

[midwayfair]

It's basically a Mu Amp -- Make it an SSRP instead. http://www.geofex.com/Article_Folders/modmuamp/modmuamp.htm

The SSRP is the version I used in the Clipper Ship. I think you know how much gain that had. But among other things, the SSRP is also less noisy and has fewer loading issues (I stuck a tone control AND volume control on it and it still had over 20dB.