Do I have this down right? (MK III valves)

[Justice1988]

v1 = input driver(Gain stage 1 and 2 for R1, R2 and L1) - Greatly affects the character of the entire amp.
v2 = split function(Gain stage 3 for R2, effects loop buffer) - Crossed with v4 in some weird way?
v3 = Gain stage 3 and 4 for L1.
v4 = Reverb input and output buffer - Crossed with v2 in some weird way?
V5 = Phase Inverter - Preamp to power polarity - Also greatly affects the character of the amp.

If that is correct, then I assume v2 and v4 are separate from v3 and the circuit in bare minimal terms would look like this...

                     - - - v3- - - - - - - -
                    /                      - - - v5
v1 - - - - - - - - - v2- - - - - v4- - /

If this is the case, would reverb be affected by the personality of v2 and/or R2 being on or off?
Would R2 being on adding to L1 be a myth(it never did anything for me in L1)?

 

[MrMarkIII]

v1 = input driver(Gain stage 1 and 2 for R1, R2 and L1) - Greatly affects the character of the entire amp.
v2 = split function(Gain stage 3 for R2, effects loop buffer) - Crossed with v4 in some weird way?
v3 = Gain stage 3 and 4 for L1.
v4 = Reverb input and output buffer - Crossed with v2 in some weird way?
V5 = Phase Inverter - Preamp to power polarity - Also greatly affects the character of the amp.

If that is correct, then I assume v2 and v4 are separate from v3 and the circuit in bare minimal terms would look like this...

                     - - - v3- - - - - - - -
                    /                      - - - v5
v1 - - - - - - - - - v2- - - - - v4- - /

If this is the case, would reverb be affected by the personality of v2 and/or R2 being on or off?
Would R2 being on adding to L1 be a myth(it never did anything for me in L1)?

I speak from twenty years of Mark III playing, not necessarily great electronic expertise.
V1: Yup. The signal hits this tube after the tone controls.
Most Fenders are like this. Most Marshalls go --> V1 tube then --> tone controls.

V2: Really what this tube does is collect and further amplify the signal after it goes through the tone controls.

V3: Lead circuitry only. Includes whatever happens with V1 but feeds into V2.
Having the Lead circuit after the tone controls is a reason why too much of that pesky bass knob makes the Lead sound tubby and indistinct. Some call this "vintage sounding". Some get nervous when they discover the best sound is not with all the knobs dimed.

V4: After V1, and V2. And V3, for that matter. Not weird, just another place for the circuit to go.
Important to consider: Reverb is BEFORE the Effects Loop, not after, as in many amps.

V5: Yup. Collects and distributes the wicked toans to the power tubes. Some think it greatly affects the sound. Some think it should be a "balanced" triode (there are two sides to each 12AX7). This is left-over from the days of tube Hi-Fi amps. Guitar amps are not, and never have been, Hi-Fi.

Yeah, R2 adds a tiny bit of gain to Lead. Tiny. Louder? No.

About the only thing you can do with the pre-amp without a soldering iron is experiment with different brands of tubes to determine, with you own ear, nuanced changes in tone. Lower gain 12AX7 types (12AT7, 12AY7, 5751, etc.) can be substituted for, well, lower gain.

YMMV.

 

[Justice1988]

Thats nifty info.
So you are saying the v1 is after the tone controls? I always though it was before the tone controls but v2 and v3 were after. Most modern amps I assume have been all v's before tone controls.

You might of answered my question on reverb vs R2. if rerverb is before the effects loop, I wonder if that means the dry signal and wet signal crossing from v2/v4.

 

[Triaxstasy]

..... Some get nervous when they discover the best sound is not with all the knobs dimed .....

:lol: :lol: :lol: 8) 8) 8)

 

[MrMarkIII]

Thats nifty info.
So you are saying the v1 is after the tone controls? I always though it was before the tone controls but v2 and v3 were after. Most modern amps I assume have been all v's before tone controls.

You might of answered my question on reverb vs R2. if rerverb is before the effects loop, I wonder if that means the dry signal and wet signal crossing from v2/v4.

V1 before the tone stack is considered somewhat vaguely as a "Fender design".
V1 after, as stated, is a "Marshall design", although it's widely known that early Marshalls are copies of the 5F6A tweed 4 x 10 Bassman. Of course, Leo copied and tweaked common Western Electric designs. IOW, neither genius invented oregano and tomatoes, but both came up with a quite decent sauce.

Too Much Information from the Amplified Parts website:
"Spring Reverb Tanks Explained and Compared"
http://www.amplifiedparts.com/tech_corner/spring_reverb_tanks_explained_and_compared

 

[Justice1988]

Straight from an email from Mesa...

Each tube has two halves. V1 is the first two stages (before and after tone controls), V2 is the FX Send and Return stages, V3 is the Lead mode, V4 is the reverb, and V5 is the output driver/phase inverter.

Cool to know. So the first half of V1 is before tone controls, second half is after.