Oberheim Matrix 6 - Tauntek 2.15 upgraded OS SN 7623278

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"24 hour sale - Upgraded Matrix 6

Fully functional and relatively clean Matrix 6. It's fully upgraded with the Tauntek 2.15 OS upgrade, and also includes the stock 2.13 EPROM should you want to revert to stock (I don't know why you would as Tauntek provides only benefits, but some people like things stock). The keyboard is level and every key works smoothly, with velocity sensing. Every button on the keypad also works, although the '0' button requires a firm press. It sounds fat and gorgeous, like an Oberheim should.

The Matrix 6 was just given a a brand new battery and thorough testing of all functions by Synapse Audio here in Portland. Tim couldn't find one thing wrong with it and says the new battery should last for more than a decade. This is as close to a worry-free vintage 80s synth as you can get these days. There are some scratches on the bottom and a few bits of rust on the metal, as you can see in the pictures, but it's very clean for a model of this vintage.

The Tauntek OS upgrade means that you can control it via a dedicated hardware interface such as the Stereoping or indeed any programmable MIDI controller. Filter sweeps will now sound like a knob being swept on an analog synth rather than a stepped, intermittent mess as with the original OS.

In addition to installing the upgraded OS, I've switched the levers to perform like you'd expect, which means reversing their direction in the menu setting, and set the interface to fast mode so you can cycle through presets and programming options using the arrow buttons rather than having to type in each parameter ever time you want to switch. You can still type in the number if you want, but cycling through filter or envelope functions using the arrow buttons is much faster.

The factory presets have been restored after the new battery install, and I've just tweaked a few of the key presets to reduce the long release tails that cut into polyphony when changing chords (it is 6 notes, after all). Programming isn't difficult using fast mode, although it requires incrementing and decrementing buttons rather than twisting knobs."