Akai AX-80

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"The Akai AX 80 is one of the most underrated polyphonic synths of yesteryear. It is an 8 voice DCO based monster. Do not be fooled by DCO's as this synth can sound as warm or as cold as you program it. There are two discrete oscillators with a sub oscillator for beefing up the low end. The oscillators provide a saw, a square with pulse-width modulation (with an independent LFO for the PWM), or a combination of both saw and square waves. There is something very raw and unique about the oscillators and are unlike other DCO based synths. They have a lot of punch, depth, and richness in pure tone. Also, oscillator two can be de-tuned beyond a simple octave jump for inbetween tunings (like adding a fifth or a third). Combined with the synths excellent chord memory, this can generate some really thick sounds that will cut through a mix like a knife slitting water.

The filter is a genuine analog CEM 3372, which also handles the amplification (a real Voltage Controlled Amp). This filter is DEEP and aggressive. It is the same filter that's in the Oberheim Xpander and Matrix 12 and a lot of that character is present with the AX 80. Not only does the filter fully self resonate, but the sine wave that it produces has a very up front and full bodied quality to it. The filter also has a High Pass so it is possible to thin out sounds when you need to make them sit in a mix better.
The modulation section is plentiful. There are separate LFO's for each oscillator (one for each DCO) and an independent LFO dedicated for the filter. Each LFO has several possible wave-shapes and resets its cycle on each keypress. This makes it possible to do pseudo-sync to BPM which a lot of analog synths aren't capable of.

The envelope section is the usual full featured faire. Two ADSR's are on-board for the filter and the VCA, and there is a setting that will route one envelope to both section's. The infamous right side problem that plagues many AX 80's has been remedied so that all the membrane buttons work and are sure to last. The other very nice feature about the AX 80 is that it is also a very playable because there is a very nice velocity modulation section that is routable to the filter and to the amp. The synth really opens up when played and the keyboard action for an 80's synth is very nice.

The synth is in very good shape. It has the usual wear and tear of a keyboard over two decades old. However, everything electronically functions. Also, the synth has been calibrated for our studio use. The internal trim pots have been set so that one of the voices is a little bit more aggressive than the others. I would enable chord memory and use this for a little more pronounced distortion tone. The user can reset and re-calibrate the synth with the internal trim pots but I think most will like the sound. Nothing is faulty about the synth either. A filter has been replaced with a brand new old-stock CEM 3372, so this was an tonal preference that the user can retune to their liking."