Schematic and layout suggestions for high gain preamp (3+1 12ax7) OR D'mble :)

[gitarzysta]

Hello

I am pre-planning to build a high gain head that would have one or two more gain stages than jcm800.
That would require 3 valves in the preamp plus one more for PI.
I am considering the following:

1. to use one extra half of 12ax7 for additional gain stage and leave the other half unused
2. To use both halves for even more dirt :)
3. One half for extra gain stage and the other one for clean channel circuit

I am looking for ready to use examples (schematics, layouts) and opinions from people who built similar amps.

Any help would be appreciated!

Gitarzysta

[tubenit]

High gain like __________ ?      You say you want it to have more gain stages then a JCM800, but does that mean "Marshall like"  also?


Marshall  (AFD mods)
Trainwreck
Dumble
Mesa Boogie
Cornford
???????????

With respect, Tubenit

[tubenit]

IF you are open to something more off the beaten path,  consider the Tweed Overdrive Special.  There is a layout board for it sold by Hoffman.  There is a list of parts & it is a proven design as a number of us has built it.  DaGeezer who was previously on the forum as a moderator came up with this design.

It is relay switchable from clean (more mild to moderate gain)  to very overdriven.  It has decent sustain to the notes  (per soundclip links)

ExpressSCH   schematic and layout here:                         http://el34world.com/Forum/index.php?topic=9636.0

Here is the GIF version of the schematic attached.

Here is a sound clip of one that I built.  NO effects pedals used :       https://www.soundclick.com/html5/v4/player.cfm?songID=9488477

With only a wah pedal :   https://www.soundclick.com/html5/v4/player.cfm?songID=11343107

Because it is cathode biased,  you can switch from JJ 6V6's or 5881/6L6's with no rebiasing. 

Because it has a PPIMV,  you can get a nice overdriven tone at reasonably moderate to low volumes.

With respect, Tubenit

[sluckey]

Here's something I put together for forum member "aro" several years ago. I did not build this and never will. I don't think aro ever built it either. It's worth the asking price and includes no tech support.   

     http://sluckeyamps.com/Visio-Aro_Project.pdf

[gitarzysta]

High gain like __________ ?      You say you want it to have more gain stages then a JCM800, but does that mean "Marshall like"  also?

I was thinking about Solano-like drive channel w/o all the bells and whistles like tube buffered FX loop etc. Not necessarily Marshall-like. But I am open for other ideas.

Sluckey - thank you, it's a pity no one ever built it :)

tubenit - so is it a Dumble-ish amp?

[gitarzysta]

Your posts got me thinking that maybe I should build a dumblish amp 😏
Is there any place I can source pre-made D'mble turret or eyelet boards?
Like Humble Overdraft Specimen.
Thanks
Gitarzysta

[tubenit]

IF you are truly wanting a Dumble clone,  get on The Amp Garage forum for tons of information, schematics, layouts.

Check with Amplified Nation or Ceriatone for the boards and chassis.  A Dumble clone would be a VERY challenging build for anyone. 

With respect, Tubenit

[adamG]

Is there any place I can source pre-made D'mble turret or eyelet boards?
Like Humble Overdraft Specimen.

Hi,

Guessing your nickname, I think you're from my territory.
If so, then mail me via PM. I could help you.

Regards,

Adam