Description
A vintage 1977 Marshall JMP MK II model 2203 Master Volume head. This amp has been modified by BFG Amplification, adding a switchable gain-boost plus rear-mounted "Growl" and "Depth" controls. An extra 12AX7 preamp tube was added for the gain boost function. This head behaves pretty much like a standard JMP with the gain boost disengaged, with a mid-gain Marshall crunch. The gain boost function tightens up the bottem end and lower mids, along with adding a serious amount of drive--fantastic for harder rock and metal. The "Growl" and "Depth" controls tweak the frequency and amount of negative feedback applied to the power section, subtly affecting the breakup characteristics of the amp. This updated classic is perfect for rockers looking for something unique and LOUD. It has been cleaned and serviced. It is fully functional and sounds great.
Overview
-Serial #: 08168J
-Manufacture Date: November 7, 1977
-Controls: Presence, Bass, Middle, Treble, Master Volume, Preamp Volume
-Power: 100 Watts
-Tubes: EL34 (4), 12AX7 (4)
-Dimensions: 29 x 11 x 9
-Weight: 45 lbs
Cosmetics
-original Tolex (see photos)
-original back panel
-one replacement knob
-hole punched for extra 12AX7
-two extra knobs added in speaker jack holes
-'Low' input replaced with boost switch
Electronics
-original transformers
-replacement electrolytic capacitors
-many replaced circuit board components
-several circuit modifications by BFG Amplification
-original power cord
