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Peavey Rockmaster


Facts | Marshall JMP-1 | Links | Your Comments!

This guitar preamp has 4 12-AX7's, yep that's right (that's 4-7027's for you military electronics geeks out there). It has three channels: clean, crunch, and ultra. The only way to access all of these is with the footswitch (one is provided if you but the unit new, or are lucky enough to get one second hand, otherwise they are about $40). New units also come with a manual, but this preamp is so easy to use, you won't need one. The clean channel has passive bass, mid, and treble, as well as a presence control. The clean channel has plenty of headroom and gives a "Fendery" tone which is great for country, jazz, or blues. The crunch and ultra channels have a shared active EQ of bass, mid, and treble. The mid control has a pull notch function in order to achieve thrash metal tones. The crunch and ultra channels both have a high gain mode, which is activated when the pre-gain dials are pulled out. This feature enables you to get amazing violin tones a la Eric Johnson (even with single coil pickups). An automatic (unadjustable) noise gate is engaged when this mode is activated. This keeps noise to a minimum, without sacrificing sustain. Every effects loop combination is provided (I use the common loop, however). There are 1V and 3V outputs, as well as an XLR output.

Click to download Peavey Rockmaster Manual.

The JMP-1 only has two tubes and thses tubes only run in parallel and not in series. The JMP-1 gets its distortion and overdrive sounds from bridged transistors, not tubes. The tubes in the Marshall JMP-1 only warm up the sound.
The Peavey Rockmaster is an all-tube preamplifier!
The Marshall JMP-1 is a smoke show BJ!

I am the Peavey Rockmaster!!!