six tubes, or only five...

[wjdunham]

Well, do you feel lucky...

I have a question about building an amp with a built-in dumbleator and reverb circuit. I have schematics for both, which if I implemented would yield an amp with a total of six preamp tubes. I would prefer to implement with only five tubes to fit better in the (Natchanis) chassis that I have, and also to keep the signal path to a minimum. I've seen pics and the schematic for the TR amp, which has only five tubes. Can I get a little advice on the best way to implement this - reverb before the dumbleator and use a single reverb recovery stage to drive the fx loop? Then I could use the other half of that tube for the FX recovery. If that's the case, then all I need is some help with the reverb recovery stage. the fender schematic has a two stage recovery circuit, but I can't say that I understand the circuit well enough to modify it without some help.
Thanks,
Bill

[briane]

I'd say your mixing up the circuits...

The dumbleator is for a dumble style, not a trainwreck.

A dumble style with a dumbleator and the common reverb circuit being used (one tube) is a total of 5 12ax7's.

The TW has no reverb or dumbleator, so 3 pre tubes. A TW would also look a bit odd if forced into a natchinis dumble style chassy.

Take a look at the posted circuits and I think it will become clear. If you take the ods-101, and add in the reverb seen on some of norms layouts, throw a dumbleator in there, then thats the cats meow.

Also, always better to punch another hole in the chassy rather than settle for a lesser design.

[dave g]

I don't think he was talking about a Wreck...TR = Two Rock.

An ODS with single tube reverb and a dlator will have 5 preamp tubes.

[wjdunham]

Sorry, I was referring to the Two Rock classic reverb, not a trainwreck, the rest of the amp I'm building will be pretty standard 80's D-type. Most reverb drivers I've seen use both halves of the tube to drive the transformer, I'm assuming to get enough current. I could put another hole in the chassis, not a big deal, I was thinking it might be better to keep the number of tube stages to a minimum to keep the noise down, and somewhat to make a more reliable amp.
Bill

[wjdunham]

I did have a look through the both the files and the discussion forums, and I found lots of interesting schematics and info, but not quite what I was looking for. It seems like the consensus is that single tube reverb isn't the best sounding. One other option is to go with the Ironsound solid state FX loop (still waiting for that for my DLite kit), but I'd have to hack up the rear panel on the chassis and move lots of things around to make that work.
Sorry if this has horse has been beaten to death here, I'm still new and there is a LOT of information to absorb. My plan was to basically implement the TR custom reverb circuit that was posted, with the small matter of figuring out what's in the little box labled "reverb" and the fact that it uses 1 and a half tubes
Bill

[Structo]

I'm no expert but I have been here a while.

Seems from my reading that there is quite a few guys that thought that one tube reverb worked fine, if we're talking about the same circuit.

You may be better off bread boarding your amp and trying several things before you commit to it in your nice chassis.

I know from experimenting with my D'Lite amp that it's once pristine build has suffered a bit with mods that either worked or didn't and were taken
out. I have the Ironsounds Loop in mine as well and while it works good for what it is, it doesn't add much to the amp. Transparency can be a good thing but with the Dumbleator you are adding a tunable loop that can greatly enhance the amp.

For the Dumble purists, it seems that the ODS and Dumbleator go hand in hand and that neither is complete without the other.

I'm sure somebody will recommend the right reverb for your amp.

[heisthl]

Forget the reverb and build the loop. Then buy the cheapest single knob EH Holy Grail you can find. They sound like tank reverb in the loop.

[wjdunham]

That would certainly make things easier I have really thought about doing just that. My only reservation is that some times it's nice to be able to take just the amp and a speaker, plug in and play, no pedals, footswitches or anything else to lug around and set up.
Bill

[talbany]

Here is Normsters layout for single tube reverb.. I have personally not built one of these since I am not a fan of spring reverb over top of an overdriven tone.. This circuit does look like it should work fine... You won't do much surfing with the single tube reverb but it will give you that added dimension if that's what your after..Somewhere around here is a schematic of a Two Rock signature Reverb.. Being an amp manufacturer feel it inappropriate to post other people's stuff..
For me personally I like the external loop out of the three options



Tony VVT