LSS- Help me understand gain staging

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Catthan

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Hi,

I've been looking at the tube layout in the LSS manual and trying to understand how gain staging works.

Apparently there are 3 gain stages, are these controllable by the switches in the front, basically for ch.2?

I think I read somewhere that the drive modes (nor. thick etc) just swap resistor and not engage valve stages.
Whereas if the fx loop is in (or jumpered) the fx level is high, that's an additional valve stage?

I would appreciate any help in getting to know my amp better.


Thanks,
T
 
Nobody?

Is there any thread where these are described?
If so please advise.

Thanks,
 
I think would be some very interesting information. Sadly, I doubt many people really know, due to the way Mesa/Boogie closely guards their schematics.
 
Each 12AX7 contains two triodes, say VxA and VxB, and each triode can be a stage of amplification.

For Lonestar, stage 1 is V1B, and V1A is used for drive stage if engaged. Then the signal goes to next stage - V2B.

On the next is an insertion of Reverb stage which is buffer by V4B (at reverb input) and then V4A (reverb output).

Then the signal goes back to V2A.

One the next, if you engaged the FX Loop, V3A (before send) and V3B (after return) will kick in as the buffer for FX Loop.

Then before signal goes to power tubes (EL84 in LSS, 6L6 or EL34 in LSC), there is a V5, a pair of triodes, used as Phase Inverter.

Hopt this helps.
 
Cool. So, basically engaging the drive control simply adds another gain stage.
 
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