What does pull fat do technically?

[boola]

A bit of a strange question but I was just wondering if someone could give a bit of a technical explanation of what pull fat does? Does it add another tube gain stage?

 

[Janglin_Jack]

I have to find my schematic again, but from memory, I think it changes the value of the V1 Cathode Bypass Cap, changing the EQ, (more bass). I double check my schematic.

Jack

 

[Boogiebabies]

The pull fat adds a 750pf treble cap in parallel to the standard 250pf treble cap.. This gives the treble cap a new value of 1000pf and a fatter/thicker treble response.

 

[boola]

Cool, thaks guys!

Is it just a percieved increase in gain then? It certainly sounds more saturated. This is on the Mark IV btw.

 

[mrd]

I don't think it's a perceived increase in gain... it IS an increase in gain. Gain is characterized by the addition of higher level harmonic content, which is what your gain/treble knob do, so if the pull shift gives a more robust treble response, then I would say that is just more gain :wink: