2011 Marshall JCM900 Hi Gain Dual Reverb 100W Head. W/foot-switch. 
 
Great Marshall amp for the money, these have a well known clean channel, possibly one of the nicest clean that Marshall ever did. 
In very good used condition overall beside one of the handle metal bracket covers which is missing. (Usual suspect) 
This amp was recently serviced and had a new set of O/P valves fitted. 
2 channel with individual volumes, gain and reverb controls
Channel A is voiced to be sparklingly clean on lower gain settings, building to a raunchy crunch when driven harder. 
Channel B takes the gain higher producing tones from silky smooth distortion to searing, saturated scream.
The JCM900 4100 is equipped with a series FX Loop with its own Level control for use with rack FX or stomp boxes.
 
Here's some specs from the web. 
Specifications
MODEL JCM900 4100
RANGE VINTAGE
TECHNOLOGY VALVE
CHANNELS 2
ELECTRONICS
WATTAGE 100W
INPUTS 1
CONTROLS PRESENCE, BASS, MIDDLE, TREBLE, PREAMP x 2, MASTER x 2, REV x 2

VALVES
PRE AMP VALVES 2 x ECC83
POWER AMP VALVES 1 x ECC83, 4 x 5881
ACCESSORIES
FOOTSWITCH PEDL-91004 INCLUDED (2 WAY FOOTCONTROLLER)
CABLES POWER
DIMENSIONS
WEIGHT (KG) 18.8
DIMENSIONS in mm
(W x H x D) 740 x 310 x 210
EFFECTS LOOP
MASTER VOLUME
PENTODE/TRIODE SWITCH
 
Comes with the original channel/reverb footswitch.
Collection from SW6 preferred, can also be delivered in London at cost. 
 
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