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Plexi MK11 has that just about breaking up sound but doesn't "sizzle" enough. Any mods other than on the schematic page or am I looking at the TMB? I have numerous pedals but seems to defeat the object.

Cascaded thru the normal channel

and or

Boot strap the cf

If you used the 470K /470K divider on the TMB channel, you can alter that to let more signal through. Its curently taking off about half the signal so replace the R42 470K resistor with 330K or 220K.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Ok, I've gone for the TMB version now and still no bite! Tried using Tele with custom pickups and two Les Pauls with amp cranked to max (using VRM). Others have mentioned the cascade mod but I'm out of my depth on the schematic as it's my first build. Any help for dummies appreciated.

TMB requires the replacement of the 500K pot to 1M, did you do that? Did you remove or change the 470Kll470K divider and to what??

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Changed the pot to 1m and removed divider. Still very clean to me. I would expect to get a very shaggy sounding amp by now.

Yeah, really. Most people think that's the max. Assuming this is the TMB channel, you might want to look at the bypass cap on the first stage. Increase it to a max of 25. And you may want to increase that plate resistor to 120-150K from 100K.
Then we would look at the PI.
The cascade mod is cool but its a big change and you'd still want to be able to use the Normal channel so you need to switch it in/out.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Ive done the mods, now it just sound muddy. I'm going back to MK11 and stick a pedal in front.

Muddy? Cascade mod? How was the normal channel comfigured?
Pretty surprised you cant get enough gain out of that mod.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Didn't get as far as the cascade mod. The amp is losing its originality and sounds nothing like the beautiful sound on other clips.

First three chords are tab channel second are normal. Definitely something wrong.

https://soundcloud.com/fluctuated-sidesplit/untitled

Bigger stick needed to hit over my head. After re checking and re checking, discovered the 1M resistors weren't moved with the VRM to the tube grid!!! Thanks for all the help

Will you try the gain mods again?

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Possibly, I'm still interested in trying the cascade mod as understanding the schematics are getting easier. I've learnt more about amplifiers this way than the original build and having almost built three in the changing between the versions the poor turret board is looking a bit sad now.

Is it with the VRM turned down for bedroom levels that you need more gain or is it with VRM on max, so full voltage applied? The preamp looses some gain when you turn down the VRM low since the preamp is scaled as well.

Mainly for bedroom levels whilst building. Hoping it blooms when in the studio as sounds a bit harsh. I'm after that woody/hollow sort of sound. With Vrm right down its still pe pretty loud.

It definitely will come to life with more juice, and bloom it will.

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Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Bloom it definately did. Barely needed the gain above half so might need to build it back to the original plexi now!