Van Halen Tribute Amp

[crgfrench]

I decided to build a high gain 20W 1x12 combo to get that Brown Sound. It will be point to point in a Hoffman Stout chassis, with fixed bias for a pair of 6V6GT output tubes. Feeling pretty happy that the iron fits the chassis perfectly, won't even require any mods at all.

20201114_002846.jpg

[Bieworm]

Looking forward to following this thread already!!!

[Riffmonster]

Awesome project!!
I will follow it carefully and wish you good luck with the build! With schematic are you starting off with?

[geoff 1965]

cool! part of his signature was dialing in the voltage with a variac so are you going to use VVR? what's the spec of the transformers Craig?
sad loss along with Peter Green and others this year!

[ViperDoc]

Dave Friedman also noted that in addition to lowering the AC voltage, EVH would rebias the output tubes to proper current.

[JMPGuitars]

Dave Friedman also noted that in addition to lowering the AC voltage, EVH would rebias the output tubes to proper current.

Proper current for what/when? That's an ambiguous statement for somebody using a variac.

[crgfrench]

Eddie was quoted saying they recorded at 89VAC mains, but the live settings varied with the venue.

[crgfrench]

With schematic are you starting off with?

Thanks -- I drew up my own schematic for it based primarily on the Ceriatone Son of Yeti layout. It's basically going to be a P2P version of the Son of Yeti in a Hoffman Stout chassis.
EDITED: R19 in the first schematic I posted should not be in the circuit, I deleted it and re-uploaded the corrected image.

Screen Shot 2020-11-14 at 7.40.51 PM.png

[crgfrench]

Here is the plan for the control panels

Screen Shot 2020-11-14 at 3.39.42 PM.png

[crgfrench]

...are you going to use VVR? what's the spec of the transformers Craig?

Not VVR, just a "Variac emulation" applied to the small AC signal instead of the large AC power source. You can see it in the schematic. I'm using the Lunchbox tranny set from Promitheus.

[Riffmonster]

With schematic are you starting off with?

Thanks -- I drew up my own schematic for it based primarily on the Ceriatone Son of Yeti layout. It's basically going to be a P2P version of the Son of Yeti in a Hoffman Stout chassis.
EDITED: R19 in the first schematic I posted should not be in the circuit, I deleted it and re-uploaded the corrected image. Screen Shot 2020-11-14 at 7.40.51 PM.png

The schematic looks very interesting! What exactly does the saturation switch do? I am not really familiar with anything like it. Thanks, I hope the project is progressing well!

[crgfrench]

Saturation switches in a pair of zeners configured as clipping diodes. 2 different pairs to choose from.

[Bieworm]

Saturation switches in a pair of zeners configured as clipping diodes. 2 different pairs to choose from.

Are the zeners still to be determined ? They're not specified on the schematic

What are the functionsof lava and magma?

[crgfrench]

Are the zeners still to be determined ?

a pair of 1N4739s and a pair of 1N4747s

What are the functions of lava and magma?

Magma sits DEEP in the bottom end of a volcano.
Lava spews HIGH out of the top end of a volcano.
Plain amplifiers sometimes label these "resonance" and "presence".

[Riffmonster]

Thanks for clarifying, makes sense!

[crgfrench]

Here is the "close to final" layout:

Screen Shot 2020-11-30 at 12.22.03 PM.png

[crgfrench]

3 changes at this point:
1) Mounted PT laydown style rather than standup to save some space in the Tweed Deluxe cabinet (even though the cab will be 1" deeper than standard)
2) 50k mid pot rather than 25k (boost mids, same as EVH Marshall)
3) might add a 3-way "Plume" switch to choose the Lava tap 4/8/16R

[crgfrench]

Most of the parts are here

20201202_135218.jpg

[Bieworm]

Most of the parts are here20201202_135218.jpg

Shake it!!! How does it sound?

No seriously.. looking forward to your new build Craig!

[crgfrench]

Just a bunch of rattley noise so far!