300T HELP

[bassboysam]

I am looking to reduce the gain on channel 2 of my 300T by using a smaller gain tube like a 12at7, this should provide me with a smoother distortion (atleast it worked with my Traynor YBA200).  Does anyone know which tube I need to replace.  Are both channels cascaded through all 4 preamp tubes or is there one tube for the clean channel, one for the dirty channel, one for the compressor?  I am assuming V4 is the splitter/driver tube.

Any info on how this circuit works  would be appreciated.

[fuzzfarmer]

why dont you just turn the gain on that channel down? or mix the two channels?

[Sunn_Tubeamp_Revival]

V3 and V4 are the driver stages.  

The V1 preamp has preamp volume. Input signal
passes through 1/2 of the 12ax7, goes through mixer then passes through the other half of the 12ax7 then on to the master volume.  

The V2 preamp is a two stage fixed gain amp.  The input signal passes through both halves of the 12ax7, then through the mixer, and then on to the master volume.

Putting a 12au7 on a 12at7 in the V2 position will lower the gain of the 2 stage amp before the mixer.  This will allow you to over drive the V1 preamp volume before both signals are combinered through the mixer ahead of the master volume.  I am not sure what disortion benefits this will provide.

A great resource person to help out would be Bob at eurotubes.com  He loves to achieve specific results and will know how.

Regards,
Chuck