Newbie question re: reducing F50 channel 2 gain

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scandoslav
Bottle Rocket
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Location: Los Angeles

Newbie question re: reducing F50 channel 2 gain

Post by scandoslav » Mon Jul 04, 2011 7:27 pm

From what I understand, the F50's signal path looks like this:

V2-Tone-V1-V3a-Master-EQ-FXLoop-V3b-PowerAmp

V1 is the "gain" tube for the second channel, right? If I were to bypass V1, would channel 2 become a clone of channel 1? Or if I wanted to dial back the gain on Channel 2, could I just put a lower-gain preamp in V1?

Is it even possible (or advisable) to bypass a preamp tube?

Also, what's the difference between "tone" and "EQ"? I thought they were the same thing.

scandoslav
Bottle Rocket
Posts: 18
Joined: Sun Jan 31, 2010 6:50 am
Location: Los Angeles

Re: Newbie question re: reducing F50 channel 2 gain

Post by scandoslav » Mon Jul 11, 2011 2:06 pm

No? Is there anybody who would know this sort of thing?

MrMarkIII
Dual Recto
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Re: Newbie question re: reducing F50 channel 2 gain

Post by MrMarkIII » Mon Jul 11, 2011 8:18 pm

The signal path is:
V1 ---> V2 ---> V3 ---> V4

V1 A = Input Stage both Channels (Signal goes here first)
V1 B = Clean Channel (Then here)

V2 A = 2nd Input Stage both Channels
V2 B = Channels 2 & 3 Boost Stage
If you wanted to reduce the gain of the Lead sounds, try a lower gain tube here (V2)
A 5751 will give you 30% less, a 12AT7 gets you 40% less.

All of these can be substituted for one another.
12AX7 = Gain Factor of 100
5751 = Gain Factor of 70
12AT7 = Gain Factor of 60
12AY7 = Gain Factor of 45
12AU7 = Gain Factor of 19

Not sure what you mean by "bypassing" a tube. If you remove it, you'll get no sound.
"Tone" or "tone stack" refers to the Treble, Middle and Bass knobs.
"EQ" could mean the same, or could refer to the Graphic EQ, if available.

scandoslav
Bottle Rocket
Posts: 18
Joined: Sun Jan 31, 2010 6:50 am
Location: Los Angeles

Re: Newbie question re: reducing F50 channel 2 gain

Post by scandoslav » Mon Jul 11, 2011 11:26 pm

Okay cool, thanks for translating.

I was operating under the mistaken assumption that V2 did nothing but add gain to the second channel.

Working from that incorrect understanding, I had been wondering if there was a way to remove V2 from the signal path; to remove the tube and then jump the gap left in the circuit by its absence. I had this in my mind as a way to make Channel 1 identical to Channel 2.


Thanks to you, I now know it doesn't work like that. I'm very glad I didn't actually attempt anything.

EDIT: Welp, the tube layout/diagram is right there in the manual. RTFM, me. RTFM.

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