Layout - PI Between Preamps

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boots
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Layout - PI Between Preamps

Post by boots »

I built a Richie TMB a couple years ago and really love it. I'm thinking about doing a similar build soon.

I was wondering what the strategy is for situating the PI tube in between the two preamp tubes? I'm thinking to adjust the layout so that the PI tube sits between the two preamps and the pair of EL84's.

Is there a good reason for the the preamp tubes being separated by the PI? Thanks!
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Boots

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Bieworm
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Re: Layout - PI Between Preamps

Post by Bieworm »

boots wrote:
Mon 04/06/20 4:12 pm
I built a Richie TMB a couple years ago and really love it. I'm thinking about doing a similar build soon.

I was wondering what the strategy is for situating the PI tube in between the two preamp tubes? I'm thinking to adjust the layout so that the PI tube sits between the two preamps and the pair of EL84's.

Is there a good reason for the the preamp tubes being separated by the PI? Thanks!
The ceriatone 18W TMB has the PI tube setting between the 2 preamp tubes...
A good reason would be that the normal and TMB channel share the same PI... plus it's better for the wiring of the TMB channel, less crossing wires.
My 2cts
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JMPGuitars
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Re: Layout - PI Between Preamps

Post by JMPGuitars »

Bieworm wrote:
Mon 04/06/20 9:43 pm
The ceriatone 18W TMB has the PI tube setting between the 2 preamp tubes...
A good reason would be that the normal and TMB channel share the same PI... plus it's better for the wiring of the TMB channel, less crossing wires.
My 2cts
They all share the same PI. One channel in one side, one channel in the other. Most of the single channel versions only use 1 input on the PI (the other half usually connected to earth via a .1uF cap).

Personally I wouldn't want to extend the plate leads farther for the PI, which has to happen to put the PI in between the preamp tubes.

Different versions of the TMBs have V2 and V3 reversed. I prefer the Superlite TMB over the other TMBs.

Thanks,
Josh
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