Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Colas LeGrippa on November 17, 2019, 08:11:47 pm

Title: Tube reverb project
Post by: Colas LeGrippa on November 17, 2019, 08:11:47 pm
Hi ,


I got rid of my cathedral digital reverb.
Was sounding ok for the guy who bought it hey hey. :icon_biggrin:
Now I want to build the real thing, all tube spring reverb. I got a bunch of trannies, a chassis and other components that are sleeping in my dusty drawers. Which model should I build ?


Thanks

Title: Re: Tube reverb project
Post by: MakerDP on November 17, 2019, 10:29:39 pm
Once upon a time I built a cool little push-pull reverb using two 12AX7's as kind of a cross between the Firefly and a design in one of KOC's books. Sounded good.
Title: Re: Tube reverb project
Post by: sluckey on November 17, 2019, 10:31:39 pm
Is there more than one?
Title: Re: Tube reverb project
Post by: Colas LeGrippa on November 18, 2019, 09:13:16 am
According to MakerDP there's aother model than the Fender one
Title: Re: Tube reverb project
Post by: jjasilli on November 18, 2019, 09:26:10 am
https://www.anatomyofguitartone.com/home/a-brief-but-complete-guide-to-guitar-reverb (https://www.anatomyofguitartone.com/home/a-brief-but-complete-guide-to-guitar-reverb)
Title: Re: Tube reverb project
Post by: PRR on November 18, 2019, 01:33:10 pm
I'm going to tack this here. Philco's 1961 reverb for home stereo.

I have seen this cross-cathode dry path (but mono) in some guitar amplifier.

Still seems to me like more parts than needed.
Title: Re: Tube reverb project
Post by: Williamblake on November 18, 2019, 05:36:21 pm
I would like to try this some day: https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.valveheaven.com/2016/10/the-lamington-reverb-an-easy-to-build-valve-reverb-unit/&ved=2ahUKEwia7qOS9fTlAhUQ66QKHci7DqkQFjAAegQIAhAB&usg=AOvVaw3496UPiORjlgGxvMQq9nUE as EF80 is cheap and it has no transformer.
I don't know the reason for the recovery stage in any reverb having a grid stopper. Would be testing that tomorrow but seriously why?
Title: Re: Tube reverb project
Post by: Colas LeGrippa on November 18, 2019, 08:06:42 pm
Very interesting indeed
Thank you guys


Colas



Title: Re: Tube reverb project
Post by: MakerDP on November 19, 2019, 11:55:11 am
I'll try and dig out my design. I'd say go to the AX84 forums and look it up... but... yeah... can't do that anymore...  :sad2:

It might be on my old blog.
Title: Re: Tube reverb project
Post by: MakerDP on November 19, 2019, 12:06:36 pm
Here ya go...  http://www.1darren1.com/2014/05/designing-all-tube-push-pull-stand.html
(This design is a great intro into the world of all things self-split. That's a fun rabbit hole that is under-explored IMO. I have a couple really nice self-split designs for power amps. It has a couple other tricks up its sleeve too... like the first-gain-stage/non-inverting-zero-gain-mix-stage in one triode.)

There is also this super-cool reverb design... https://www.modkitsdiy.com/kit/wave
I built that kit. Very nice rich reverb. What's cool about the kit is that if you end up not really digging the reverb it makes a great stand-alone preamp or D-Lator w/verb platform.
Title: Re: Tube reverb project
Post by: kagliostro on November 19, 2019, 02:20:51 pm
Ciao Colas

This is different but I don't think you want to build your own spring tank unit

(https://i.imgur.com/cYEdZuN.jpg)

---

Read here about the patent and the tank Vox used

http://www.voxshowroom.com/uk/misc/reverb_hood.html (http://www.voxshowroom.com/uk/misc/reverb_hood.html)

---

(https://i.imgur.com/o4hfMOC.jpg)

(https://i.imgur.com/RxcaPAs.jpg)

(https://i.imgur.com/OBuYKrq.jpg)

(https://i.imgur.com/rehdOvg.jpg)

Franco
Title: Re: Tube reverb project
Post by: Colas LeGrippa on November 20, 2019, 03:47:27 pm
Grazie mille Franco sei com un padre per me...
My spanish is much better than my italian...


I think there are simpler reverbs than the Vox one but iit s worth take a look at it
Title: Re: Tube reverb project
Post by: sluckey on November 20, 2019, 03:57:33 pm
Here's a dead nuts simple reverb...

You need a second small guitar amp, champ would be fine, but any amp will work. Call it the reverb amp. You also need a Fender style reverb tank, 4 to 8Ω input, high z output. Play guitar through main amp. Connect reverb tank input to the speaker of your main amp. Connect reverb tank output to input jack of the reverb amp. You won't be disappointed.

If you like the sound you may consider mounting the reverb tank inside the reverb amp. Then you only need a speaker cable to connect the tank input to your main amp. Tank output is connected inside the second amp.

Title: Re: Tube reverb project
Post by: kagliostro on November 20, 2019, 04:18:19 pm
As Steve say

(https://i.imgur.com/dKrQCC6.png)

this Gibson has the reverb tank but require one other amp to drive it

Franco
Title: Re: Tube reverb project
Post by: Colas LeGrippa on November 21, 2019, 10:21:37 am
I ll sure give a try to Sluckey's suggestion B4 getting into a time consuming project, since I have a couple of amplifiers laying around.


Thanks guys for comments, links and schems.
Really appreciated.


Jack
Title: Re: Tube reverb project
Post by: SILVERGUN on November 21, 2019, 10:38:48 am
If you absolutely have to have the best reverb you better get busy pouring concrete:
Title: Re: Tube reverb project
Post by: shooter on November 21, 2019, 11:27:05 am
I'm at war with my computer for CONTROL so audio is shutdown, the photographer pulled off (or doctored in SW:) a great shot, light, shadow, unfocused shot of Christ, coloration, I can already hear the reverb  :laugh:

thanks for waking up n sharing  :icon_biggrin:
Title: Re: Tube reverb project
Post by: sluckey on November 21, 2019, 11:43:02 am
Colas, I would start off with a series connected 25Ω to 50Ω resistor between the amp speaker and the reverb tank. I would also experiment with series coupling caps. You really only want to send high frequencies to the tank. Kinda like a simple hi freq crossover.
Title: Re: Tube reverb project
Post by: kagliostro on November 21, 2019, 01:07:46 pm
Ciao Colas

if I can, this will be my suggestion (as you are going to do something that is very similar)

Build a small stand alone chassis & cabinet

put inside the tank and other components as to be used with a driver amp to obtain reverb to go to the imput of your amp

and .....

as you are really near there ....


put the components you need to use this standalone chassis as to obtain also an Herzog output from the same device (really few components)

(https://i.imgur.com/UYqwLmB.jpg)

(https://i.imgur.com/TYq9jxU.png)

(https://i.imgur.com/evqZtuW.jpg)

---

SILVERGUN experimented with the Herzog and build a nice unit

http://el34world.com/Forum/index.php?topic=16934.msg168118#msg168118 (http://el34world.com/Forum/index.php?topic=16934.msg168118#msg168118)

Franco


p.s.: Does someone remember which was a stereo guitar amp that had the output of one channel connected to the imput of a tank and the output of the tank to the other channel ???
Title: Re: Tube reverb project
Post by: shooter on November 21, 2019, 02:04:11 pm
Quote
which was a stereo guitar amp
don't know on reverb, the SET amp did kinda that with the echo unit,  "possible" to use as an example  :dontknow:
Title: Re: Tube reverb project
Post by: sluckey on November 21, 2019, 02:06:44 pm
This...

     https://el34world.com/charts/Schematics/files/Ampeg/Ampeg_et1_echotwin.pdf
Title: Re: Tube reverb project
Post by: shooter on November 21, 2019, 02:38:51 pm
yup, just too lazy to look it up  :icon_biggrin:
Title: Re: Tube reverb project
Post by: kagliostro on November 21, 2019, 03:17:02 pm
Many Thanks Steve

Franco
Title: Re: Tube reverb project
Post by: Colas LeGrippa on December 05, 2019, 09:46:34 pm
Everything's hooked up right now, sounds amazing !


From the OT 8ohm tap of my main amp and right into the reverb tank 
and from the reverb tank out to a pp 6V6 connected to an alnico speaker.
Much better than a digital reverb that s for sure.
The reverb comin' out from a different amp than the dry signal gives a very interesting dimension
and.improves my tone by 50 %. ( according to my tone dimension meter... :laugh: )
Title: Re: Tube reverb project
Post by: sluckey on December 05, 2019, 09:52:52 pm
 :thumbsup: