7x12AX7 in Mark V?

[guitarmaster]

:!:

 

[Bullen]

The reverb is tube driven and the fx loop is probably tube buffered and perhaps the Extreme uses another gain stage.

 

[MetalMatt]

Mesa's Quad Preamp has 8...

 

[4Eyes]

my opinion:

3x12AX7 - it covers classic mark clean with mark lead with all modes which could be only few capacitors in tone circuits - it's 5 stages: 3 for clean, 3+2 for lead and 3+1 (other than 2 stages from lead circuit) for mark I mode. or if you want - hybrid of lonestar and mark preamp circuits with some ugrades
1x12AX7 - serial tube fx loop
1x12AX7 - tube reverb circuit
1x12AX7 - phase inverter
1x12AX7 - for British-inspired EDGE mode on channel 2. british style circuit (for example soldano, or recto..and of course marshalls) differs from mark style circuit. so I think, this could be place for adding another one 12AX7 in the circuit
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7x12AX7

just my .02, but I could be right..and maybe not

 

[guitarmaster]

:!:

 

[kiff]

also, along what 4eyes was saying; the fact they're trying(?) to faithfully recreate a markI, IIC+ and a IV (not to mention all the others) could require that many to make the required signal paths/circuits

 

[4Eyes]

kiff: maybe, but MK IIC+ and MK IV circuits are very similar. If I would be a circuit designer, it would be much easier for me to add some optocouplers and relays to switch few capacitors and resistors than adding another one 12AX7 tube to create whole new signal path. espacially when we are talking about one channel. One channel and 2 different signal paths for different, but similar, modes/circuits... :? maybe, but I don't think so.

btw how about extreme mode? did anybody noticed, that lead channel on mk V doesn't have lead drive control as it was on previous mark models? I think, this mk iic/mk iv/extreme switch sets 3 different preseted values for lead drive control, inter alia

look at the triaxis, for example. It has 8modes, but the circuit is only one signal path (mark lead) with lot of relays and optocouplers. and I think that's the way how mark V was designed. or maybe better example - look at the clean channel of MK V, there are 3 modes and I think they took it from Lonestar (like they did it with roadking/roadster). and this 3 modes are provided with one 3-pole switch which switches between 2 capacitors and 2 resistors (capacitor and resitor in series, in 2 paths) in tone controls circuit. I hope you know what I want to say

when we look at the modes of the MK V's channel 2 (crunch, edge, mark I). crunch could be some variation of MK IV's rhytm 2 channel, mark I could be this 3 stages, common for clean chanel and this crunch, plus another one added after first input stage. In same way Lonestar drive/lead channel is designed. and finally edge mode, on the mesa's site they wrote it's british inspired circuit. and as I know british circuits have tone controls at the end of the preamp signal path. so I think they added another 2 stages (1x12AX7) wired as cathode follower and placed it after MK I stage and in front of tone controls (input stage - mk I stage - 2 stages for cathode follower - tone controls). some crunch channels of Engl amps are designed in this way and believe or not nomad's channel 2 and 3, too. Or maybe it could be only input stage - cathode follover - tone controls and in this way Vox AC's are designed.

or there is other one possible option - 3 stages common for mark clean. at the place where are tone controls there is only gain control, after this 3 stages there could be cathode follower and then tone controls. in this way rectifier channel is designed.

so I think this is better way how to use another one 12AX7 effectively than creating of two signal paths for MK IIC+ and MK IV modes which circuits are very, very similar.

but of course, I could not be right and as I said it's only my way of thinking.

edit: and when I look back, my way of thinking is "little bit" complicated :lol: (I would like to see Mark V schematic )

 

[nosajwp]

Heartbreaker has 7!