Edited highlights from; http://www.thewho.net/whotabs/equipment/pa/pa_quad.html
I own a M.A.V.I.S audio desk. I have used the desk for my recordings and used it for many bands I was in. It still all works. The manufacture of MAVIS committed suicide so there is no origination documents; however, I was informed that they were made in England. These desks were built with the finest craftsmanship with engraved lettering, anodized aluminum pullout channels and master tracks, Penny Giles faders, built in tri-amp crossovers and weighs 285 lbs in the flight case with power supply.
The M.A.V.I.S. (musical augmentation voicing instrumentation system) desks are 15 channel with input attenuator, four-band EQ, pan, cue, pre post EQ-switched echo send, two monitor sends and four track-assignment switches.
They are encased in their own metal enclosure with a buss connector. The faders were made by Penny Giles in England. The face panels are anodized aluminum with white back-filled script lettering. The blue section is four tracks with track 1 and 2 assignable to a built in tri-amp crossover, which sends the six signals tr1-hi 1-mid 1-lo tr2-hi 2-mid 2-lo through the mains snake and are split off with two fans snakes to stage left and right and connected to the amplifier inputs. Track 3 and 4 can be sub-mixed into track 1 and 2 or outputted to a recorder and both have four-band EQ. The two monitor and one echo sends also have four-band EQ. You can also monitor any one of the outputs using two rotary switches, which assigned the signals to tr 3 and tr 4 V.U. meters.
You can see that there are 19 back-lighted V.U. meters on the top of the desks. The output driver circuits use 300 mw current amplifiers, which drive the balanced lo-z transformers to push the signal down the long length of cable without signal degradation. Each snake had an additional five lines, which were accessed from an aux connector on the back of the desks so you could use 10 more lo-z lines for spares and stage intercom. Each mains snake has one huge connector that connects to its mate on the back of the desk.
I was told that ShowCo. also had a few of these desks. There were 28 made like as in the pictures.
There were two more made with a middle switching console. They were just like the first model except for having five-band EQ and a quad joy stick instead of pan for each of the 15 channels and also had a middle quad switching desk. They were made mirrored brother and sister with the blue track sections on the traditional left and the other desk tracks on the right side.
