Produced from 1976 to 1981. The Mark III contained the new ARP 4075 filter. Otherwise its internals it were virtually identical to the Mark II, except for its overall appearance and sound quality, which had undergone further improvement. The chassis was changed to match the classic ARP colors, which is known to be black-orange. The synthetic backplate was replaced with a steel case, as was the rest of the panel, while the keyboard visibly protruded from the case: this choice, common to other ARP instruments of the same period, made the keys prone to impacts and breaking during transport. The Mark III used a unique tone bending control device, called PPC (Proportional Pitch Control), where three pressure-sensitive buttons were used to control the bending and vibrato effects; other Odyssey models used a simple knob for this purpose. At the same time, a conversion kit was available to install the PPC on models with knob control as well. The Odyssey Mark III is considered the most famous of the Odyssey models. The ARP Mark III had the high-level XLR-type output, replacing the 1/4 jack socket as in earlier models. The outputs of all models were of the unbalanced type.

All our instruments are delivered with 12 months of warranty after being fully revised and tested in our workshop, in both their mechanical and electric components.