Crazy talk: 5F1 + 6G15 = Champion Surfer?

[BobSmith]

Wondering what to build next...

I’m still pretty new to these circuits and done a few (six!) that have come out pretty nice.  I’m hoping to try something new...  but need some help with the design.

The idea:
I like the thought of a real tube reverb.  I like small amps.  So I was thinking, could I mash a 6G15 (reverb unit) and a 5F1 (Champ) together in a box?  I’d like to make a head unit, powered by one power supply, maybe tube rectify the reverb? .  I’d also want to be able to use the reverb on its own if I wanted (basically have a send and return jacks for the reverb to be used stand alone, may require a bypass switch).

Issues
Power Transformer
It would be two 6v6s, and three 12a_7s.  Just eyeballing, it seems a 5e3 PT would be sufficient.

Rectifier and filtering
I’d think a 5y3 would be able to supply enough for both parts (again, pretty close to a 5e3 ) and ditch the diode rectifiers.  Couldn’t I use the same filter caps and choke for both?  Hoffman and fender use 40uf for reverb, others use 22uf.  Champ seems to be 8uf and 16uf.  Is there a happy value that may work for both?  How about dropping resistors?  Suggestions?

Grounding
Now this could be a real issue.  Apparently there are issues with using a chassis ground in the circuit.  Some people recommend isolating inputs and such, but I doubt this would be possible if co-existing with a champ.

Bypass point
Basically I need to pick a location for a passive effects loop and wire that to a switch that could isolates and activates the reverb as an outboard effect.

Chassis, cab and board
I’m comfortable with making cutouts in a project chassis.  Id need something bigger than a 5e3 chassis.  There is a guy in Canada that does blank chassis that would probably do the trick (basically a long 5e3, may also need some mount points on the sides). I’d need room for a 4 transformers: PT, choke, OT and reverb.  Gonna get crowded!  I have a head cabinet that was meant for a 5e3 laying around.  It could fit a full sized reverb tank.  I’d probably need to make a custom turret board too, it will be my first time doing that but it doesn’t look too hard.

Dunno.  Stupid idea?  Help me shoot some ideas. 

[VMS]

I would probably start approaching this type of project with this vibro king schematic (last page) and replace the V4b with champ 6V6 power section.


https://el34world.com/charts/Schematics/files/Fender/Fender_vibro_king_manual.pdf

[bmccowan]

There are a few Champ Reverb ideas in the schematic .sch files. I have not built any of them, but wondering if others on here have:
http://el34world.com/charts/SchFiles.php

[kagliostro]

May be a revibe can be of your interest ?

http://sluckeyamps.com/revibe/revibe.pdf

I think that the output of the transformer can also (alternatively, using a switch) used to drive a speaker instead of the Reverb Tank

Franco

[sluckey]

That's a brilliant idea K! 

[BobSmith]

Hmm, I could consider a Revibe. That seems really cool.  (And would save me the trouble of mashing circuits.).

Where does one acquire a chassis for a Revibe?  Only Weber seems to have one...

I wouldn’t mind putting one in a Hammond cage chassis like the Lunchbox blues JR I just built (Hammond 1441-26) and mount the tank on the cage cover.  Only problem is the dimensions are 16 in x 8 in x 2 in. Which would mean a shorter tank.  The 17 in version is too big in other directions.  Is there a worthy tank that would befit both the circuit and that chassis?

[sluckey]

Here's an idea...

     http://sluckeyamps.com/revibe/revibe.htm

[PRR]

6G15 was a super-deluxe box which may have cost as much as a Champ.

After the novelty wore off Leo contrived a much simpler reverb in the fine Blackface models. Why not face of a BF, strength of a Champ?

[BobSmith]

Here's an idea...

     http://sluckeyamps.com/revibe/revibe.htm

That’s really nice, but where, oh where to get the chassis?
 I could probably get this done with the chassis the Mod “The Wave” kit uses.

[BobSmith]

6G15 was a super-deluxe box which may have cost as much as a Champ.

After the novelty wore off Leo contrived a much simpler reverb in the fine Blackface models. Why not face of a BF, strength of a Champ?

This is a nice circuit, but I really want to do more of the g15 over the top-ness. ;)

I was checking out the Vicky Reverberator too.  That’s probably basically what the Revibe is.

[sluckey]

That’s really nice, but where, oh where to get the chassis?

Hoffman and Mojotone both have a 17"L x 6 1/2"W x 2 1/2"H blank chassis. Several of my style have been built using this size chassis.

[Greenwichpaul]

This is a nice circuit, but I really want to do more of the g15 over the top-ness. ;)

I was checking out the Vicky Reverberator too.  That’s probably basically what the Revibe is.

Victoria state the Reverberato is based on the blackface so I would guess it's 12AT7 for the reverb driver plus 1/2 12AX7 for recovery, then presumably 2 1/2 tubes for the trem.

THat said, I'd love to see a circcuit for the 12AT7 reverb combined with harmonic vibrato and s/s rectification, that's more compact/less complex than the Revibe (the Torevibe is simply a bias trem I think). Please build one!

[Willabe]

compact/less complex than the Revibe (the Torevibe is simply a bias trem I think).

No, Torevibe is harmonic vibrato.

See post's below.

[Greenwichpaul]

compact/less complex than the Revibe (the Torevibe is simply a bias trem I think).

No, Torevibe is harmonic vibrato.

There have been contradictory reports around but Weber state "Tore-Vibe.... designed by Tore T. 6G15 Reverb circuit married to Tore-designed bias modulating Tremolo rather than the harmonic vibrato of the ReVibe.'

Again, I hope one day someone here sorts us out a 4-tube reverb/harmonic trem, it would be awesome and I could sell my FET version!

[sluckey]

No, Torevibe is harmonic vibrato.

Don't think so...

     https://www.tedweber.com/media/kits/5h15t_schem.jpg

[BobSmith]

This is a nice circuit, but I really want to do more of the g15 over the top-ness. ;)

I was checking out the Vicky Reverberator too.  That’s probably basically what the Revibe is.

Victoria state the Reverberato is based on the blackface so I would guess it's 12AT7 for the reverb driver plus 1/2 12AX7 for recovery, then presumably 2 1/2 tubes for the trem.

THat said, I'd love to see a circcuit for the 12AT7 reverb combined with harmonic vibrato and s/s rectification, that's more compact/less complex than the Revibe (the Torevibe is simply a bias trem I think). Please build one!

The tube set for the Reverberato is 1 x 5Y3, 4 x 12AX7, 1 x 12AT7

It is a 65 BF reverb circuit as you stated.  But the vibrato has 3 1/2 12ax7, supposedly a fender concert vibrato, so an extra tube?  Weird. It has a 5y3 rectifier and both twin and concert were solid state.

They also came out with a solid state version called the reverberammo, built out of an army surplus ammo box.   It has the same tube compliment minus 5y3 and a short reverb tank to fit.  (Tank is attached to cover which you need to remove and plug in each time you setup.). Victoria put a guts shot (blurry) on Facebook.

[BobSmith]

Hoffman and Mojotone both have a 17"L x 6 1/2"W x 2 1/2"H blank chassis. Several of my style have been built using this size chassis.

Ok, I see it now.  Yours didn’t look aluminum at first take, so I was confused.  It would be nice if there were one without the wings.   I may go with Hammond again, now that I know how to work with their stuff. 

[VMS]

Again, I hope one day someone here sorts us out a 4-tube reverb/harmonic trem, it would be awesome and I could sell my FET version!

Maybe something like this could work with some tweaking.
Upping the gain on first triode and some mixing resistors might be needed.

[sluckey]

My chassis was made by a forum member. It's a very simple "C" fold style chassis, 17 x 6.5 x 2.5. There are no metal end pieces. That's why you see wood end pieces. I never planned to put this in a cab.

If I had to build another I would use the Mojo chassis. I definitely would not use a short tank on this or any 6G15 circuit. To me, that seems like building a 100W amp and pairing it with an 8" speaker.

[Willabe]

There have been contradictory reports around but Weber state "Tore-Vibe.... designed by Tore T. 6G15 Reverb circuit married to Tore-designed bias modulating Tremolo rather than the harmonic vibrato of the ReVibe.'

Again, I hope one day someone here sorts us out a 4-tube reverb/harmonic trem, it would be awesome and I could sell my FET version!

No, Torevibe is harmonic vibrato.

Don't think so...

     https://www.tedweber.com/media/kits/5h15t_schem.jpg

Sorry, I was thinking of Doug's/Sluckey's Revibe. It is a 2 tube (4 sections 12AX7) harmonic vibrato.

Here's the link to Doug's with schemo and layout;

https://el34world.com/schematics.htm#Hoffman_ReVibe_

And here's the link to Sluckey's, documented the whole build, including schemo, layout and pictures;

http://sluckeyamps.com/revibe/revibe.htm

[DummyLoad]

VibroSE. i have not built. check for errors. published voltages are estimates. based on rev. E/F of vibroking circuit. some part values changed.

i added switchable NFB - IMO SE needs some to tighten up the lows. i added a master vol + a gain stage to mimic overall gain structure of the original since the SE is missing the gain of the LTPI.

--pete


EDIT - schema has error - revised and attached version 1a.

[BobSmith]

VibroSE. i have not built. check for errors. published voltages are estimates. based on rev. E/F of vibroking circuit. some part values changed.

i added switchable NFB - IMO SE needs some to tighten up the lows. i added a master vol + a gain stage to mimic overall gain structure of the original since the SE is missing the gain of the LTPI.

--pete

Thanks for putting this up.  (And justifying the original title as we took a tangent into revibes!  Both are cool and one or the other is on my plate next...)

Very interesting! I’m curious why you went with a 6L6.  There seem to be so few SE amps this way.  (And I’m not sure why)

I’m also wondering what cool circuit drawing program you’re using.  Looks so nice and simple, but I’m sure it’s probably $$$.  I tried some of the free ones but I gave up after I found myself having to draw a lot of the elements we commonly use here.

[SILVERGUN]

VibroSE. i have not built. check for errors

I've been looking for a reason to do a VK and now that I'm hooked on SE I'm gonna hang on to this schematic.

Pete, after a brief peruse, I only have one issue. I don't see the function of SW1 as drawn. 

[BobSmith]

VibroSE. i have not built. check for errors

Pete, after a brief peruse, I only have one issue. I don't see the function of SW1 as drawn. 

It’s a placebo switch.

[sluckey]

It's used as a convenient mounting place for R14.   

[DummyLoad]

oops! has a wire there that shouldn't be there! @&^%*. yea, it's a WTFDTD switch as drawn.   

fixted n attached.

--pete

[DummyLoad]

>> circuit drawing program you’re using

express PCB - it's free. it's about as easy to use as it gets, more or less.

most of the objects and a few of symbols are custom. download it and you can have mine to save some time. i'll archive them and post them later if you do.

for the PDF format file generation - i use a print to PDF application.

--pete

[kagliostro]

Given that when I indicated Sluchey's revibe I did it also because in that way you would have had a safe and already tested circuit complete with a definitive scheme and, above all, a valid Layout

An idea has been spinning in my head for a long time

It would be a revibe with speaker output, taken from the secondary of the transformer that drives the spring reverberation through a rotary switch, in other position of the rotary switch I would insert a dummy load so as to also have an "Herzog function"



see here (from our friend SILVERGUN)

http://el34world.com/Forum/index.php?topic=17218.msg175247#msg175247

As for the tremolo section, the idea would be to use Merlin's Vibrotron circuit borrowed from the VOX AC30 circuit, therefore with, alternatively, tremolo and true vibrato (many call the tremolo as vibrato but they are not the same thing)



About the chassis, if you have a minimum of skill about construction (the same you require if you get a blank chassis and must make holes in it), my council is to use aluminium C profiles in junction with a  2 mm thick aluminium sheet




see near the bottom here (from our friend Heinz)

http://jschem.bplaced.net/t7/

obviously you can arrange the tube holes on the top of the chassis instead of the side

to join the c profiles to the sheet I use blind rivets



But this way you must consider there isn't a whole ready unique schematic and a proven Layout

However I consider the aluminum C profile  + aluminium sheet a good and easy way to have a custom chassis where you can decide your preferred measures

Franco