Mesa M-Pulse 360 / 600

[mozwell]

Found this in my travels, thought it may help someone here.
Interesting how they drive the Mosfet output stage directly from a cathode follower 12AX7.

the footswitch info may be helpful to repair a damaged footswitch (or make your own)

[J M Fahey]

Very interesting, thanks.
Quite close in concept to what a Mos Powered Ampeg SVT is.
Don´t think it´s casual.
Must be a beast of an amp anyway; specially the +/-90V powered one.
I think I´ll add a few extra IRFP250 to my own B300 series and rise rail voltages accordingly.
Strange they didn´t use a Class H/F/G output stage, it might still be driven by that 12AX7.

[MarkusBass]

Thanks for sharing. This is (almost) exactly the same idea that is used in Ampeg SVT3Pro.
JMF, do you mean Hartke B300, or Behringer B300?

Mark

[J M Fahey]

Hi Mark.
No, I meant the FAHEY B300 I build and sell commercially in Argentina.
You can see them in the Video I linked to in post#27 in:
http://music-electronics-forum.com/t27336/
Those are old ones, still bipolar output (2N3773 , I always liked "industrial" transistors, gladly sacrifice "Hi Fi" or bandwidth for robustness).
The new ones use IRFP250 , cheap and rugged beasts.