Jim Kelley amps are legendary, and the FACS model was the top of the line. "FACS" stands for Foot Activated Channel Switching and was an ingenious way to switch between clean and overdriven sounds before regular channel switching was a thing.
The way it works is that the amp has two completely independent channels that are essentially identical. There is a special power attenuator that came with the amp (included) that is activated by a footswitch and assigned to one channel.
This means you can dial in one channel for a clean or edge-of-overdrive tone, and crank the other channel for lead tones. When you switch channels the attenuator is activated on the lead channel and its volume is controlled by the attenuator. What's really cool and unique about this concept is that unlike modern "master volumes", the attenuator is after the output stage, meaning the lead tone has all the harmonic richness that comes from overdriving the output tubes.
This amp has just received brand new filter caps and a brand new set of JJ 6V6 output tubes. it is running well and sounding great, but there is a small amount of residual hum that seems to be inherent to the design/layout. I have worked on four FACS amps over the years, and they all had some level of noise. Nothing that's noticeable when playing, but it's there.
The original attenuator is included, but the umbilical cord that connects it to the amp is missing. I believe these might still be available from Jim Kelley, or would be easy for any tech to make. It's just an XLR to XLR cable. Also missing is the channel switching footswith, but that's just a basic on/off switch that's commonly available.
The amp is fully usable as-is, both channels work and sound great.
Speaker is a 1980s JBL E120 that I believe came with the amp.
I've seen at least one Kelley FACS sell recently in excess of $14,000, and new Kelley amps are sold auction style by Jim Kelley for significantly more than that.
