The Amp Garage

So I'm gearing up for something I've wanted to do for many years: an amp with both a 2204 (Marshall MV aka JCM800) preamp and an AB763 (Fender Blackface) Normal Channel preamp. I want both sides totally parallel and on at all time (dedicated inputs) so I can use an A/B switch (as if I was using two ...

ampfab wrote:If using the 18w transformers, I would use the ez81 rectifier of convert it to solid state

Most 18W PTs have a 5V tap on the rectifier filament winding.

I know cause I'm currently building a 6V6 amp with a GZ34 recto using 18W iron.

I know the Classictone and Trinity do, at least

6V6 is still going to be very loud, just less so

I suggest a 18W set of iron instead of Deluxe, the higher primary Z and the lower B+ will scale down the original better.

I have some experience with the CAE circuits. In my experience when cloning a mod vs an established circuit I've found that in most cases any part value that is stock in the original circuit that is close in value to the objective circuit of the mod is usually kept. What I mean by this is that most...

Start by building a JTM45 instead, with KT66s, already more manageable than a "50W" EL34 build (really more like 70-80W while the JTM45 is around 35W) Include the PPIMV (LarMar), worst case you leave it up and it changes nothing. If that still doesn't do it, use an attenuator. And of course stay awa...

So reading around, it would seem the CAE 3+ preamp is based on those mods so I looked at the schematic to figure out the difference. The crunch side is indeed very JCM800ish, except there is no cold stage (so more gain right there, both stages are biased with a 2k7) and the 500k/500p peaker before t...

I am researching building a Plexi style for a friend in a Green Day tribute band. Doesn't have to be exact replica, but it appears he's mostly been using a modded 1959SLP with a "crunch" mod (apparently now done by CAE as the Crunch mod). Listening to some of the clips, it sounds very JCM800ish exce...

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www.tubesandmore.com
www.mojotone.com

The specialized sites make it easier to find the type of parts we need for amp building/modding.

also try decreasing gain pot to 250k to keep noise down Oh, noise is currently not at an issue. The current 2204 is a single-channel, so I leave it set at "AC/DC" gain all the time and we don't hear a peep on stage when I'm not playing. Might be different on the new build in the "clipped" mode thou...

Put a 10-25k tail resistor on the Jose rig but no pot, or put a 25k pot as the tail instead of the volume. The 25k pot is now crush control. Congrats! Your amp doesn't sound like a Lab Series anymore. :) My recent 4 stager has a 6-position rotary clip control with RED, 20v, 12v, Transistors, and 1n...

Don't forget the resonance mod on the negative feedback too. The current amp already has that :twisted: I also subbed in a 250k pot for the NFB resistor (with a permanent 22k) for many NFB options. Very handy! Oh I got that too (it's my experimenting amp I guess). Turns out I like a little less NFB...

to get more gain, I recommend the levi #34 mods: .1u bypass cap on the 10k cathode and .68 on the 820 (or .47 on 1k) The current 2204 build used to have a .68 on the 820 (I'm assuming we're talking about V2a, aka the stage that "drives" the cathode follower) and I removed it a long time ago. The am...

John_P_WI wrote: Don't forget the resonance mod on the negative feedback too.

The current amp already has that

Lets see the schematics showing these mods since I don't have any. :) Hmmm, Jose, Fortin, Cameron, Friedman, Niks Chupa - the LA 80's amps are back, bring out the long hair and real Charvels too :lol: Hehe, that works out, I have a San Dimas inspired Warmoth, one of my favorite guitars even though ...

Lets see the schematics showing these mods since I don't have any. :) Unloading my mind to paper right now When it's concise enough I'll commit it to the computer and share I usually go straight from my mind to the turret layout, but for more complex projets like that, a schematic is a key step! I ...