Recommend single tube reverb? No inductors allowed, just one tube

[KivettBednar]

Hey y’all! Looking for good examples of single tube reverb schematics. No inductors/transformers allowed. No paralleling triodes. Just one triode send, one triode receive.

Any recommendations? Much appreciated!

[martin manning]

This came up (again) just recently: http://www.channelroadamps.com/articles/reverb_driver/ Seems to fit your spec except the driver is a pentode.

[KivettBednar]

Thank you man!~

Any specific amps that have them in them?

[Stevem]

There may be no one that loves the sound of tubes more then me, but since no amp ever made that has the reverb in the signal chain where it should be, that being dead last then I say just get yourself a good reverb stomp box to go after your guitar and be done with it!

Reverb pans sound there absolute best when there driven by high current which 12AX7s do not have , my pick would be a 12bH7 tube if your PT has enough V+ current left after powering all of your other tubes in the amp.

The normal parallel plate reverb driver set up of a 12at7 can't even muster up 8 ma of current, just one plate section of a 12bh7 can summon up over 11ma!

[martin manning]

Any specific amps that have them in them?

I have seen transformerless reverb drivers (EL84 pentode, e.g.) in a few commercial amp schematics, but I can't recall any one-tube designs like the one linked. The clip sounds pretty good.

[didit]

Hello -

Believe Billy Zoom's Little Kahuna tube effect has a reverb circuit very similar to the Channel Road design, but based the larger pentode in an ECL82. As Martin says, the samples shared sound quite good and the engineering notes are sound.

Best .. Ian

[thetragichero]

I've used a 12dw7 for this to pretty good effect

[thetragichero]

the au7 triode on the send and ax7 triode on receive. i claim authorship on this.... i looked up a ton of different single tube reverbs for inspiration and scribbled this on the back of a paper plate

[KivettBednar]

Right on. The Benson reverb uses that tube, I believe.

[thetragichero]

reverb tank was the high impedance kind. like 2k/2k. the low impedance type most likely will need a transformer. important information obviously lok

[jcool666]

I dont know of any commercial examples, but you could do a foldback reverb loop. You wouldnt need to use any tubes for the send portion, just 1 for recovery and mixer. The easiest way is to use a dwell control to take the signal from the output transformer and feed it directly into the tank. Kevin O'Connor had a section of his reverb chapter that outlined how to do a foldback reverb loop in The Ultimate Tone (vol. 1) By all accounts its not the strongest reverb effect, but at least as good as using a 12AX7 to drive a piezo transducer, a la Silvertone.

[echuta13]

I suspect similar to what Swart uses? I've been wanting to do a reverb like this for a spell. The 12DW7 seems like great tube for this.

https://guitar.com/guides/diy-workshop/ ... amplifier/

[jcool666]

No. The circuit I'm talking about takes the signal from the secondary on the output transformer and pushes it directly into the input of an 8 ohm tank. Both halves of a 12ax7 are used on the recovery side, one to amplify and the other to mix into the preamp. You can either use a fixed resistor or a dwell knob to tame the signal down so it doesnt overload the tank.

[T Wilcox]

Any specific amps that have them in them?

I have seen transformerless reverb drivers (EL84 pentode, e.g.) in a few commercial amp schematics, but I can't recall any one-tube designs like the one linked. The clip sounds pretty good.

Going thru some old threads I saw this posted from Martin 2 years ago and it reminded me of this thread
uses the 12DW7 one tube like in the swart amps
Hope it helps!

https://ampgarage.com/forum/viewtopic.php?f=6&t=31498

[SoulFetish]

So, I've shared this over at MEF, but this is a 1-tube (abbreviated) reverb circuit I designed to retrofit into my buddy's Silvertone 1474 to replace the stock one.
Inspired by Channel Roads article. Mine uses 6U8A 9-pin pentode/triode tube. Personally, I prefer a direct CCS driven reverb to most all transformer driven reverbs.

6U8A_Reverb.jpg