A few weeks ago a friend gave me this curious looking box. A Suzuki synthesizer? Surely not.
Here’s what we know. There are two DCOs offering sawtooth and square waveforms (the square waveform can mix up to 4 octaves of square waves together). There is an analogue 24db Low Pass Filter (SSM Filter IC). Two amp envelopes (yes two!), filter envelope, two LFOs (hardwired to osc pitch and filter frequency), chorus effect and a basic record/playback sequencer.
Unfortunately it’s not a true polyphonic synth. It’s paraphonic, meaning that there is only one filter and amp for all 8 voices (actually there are two amps for a slightly odd ‘double’ mode which gives 2 x 4 voices with an interval setting for detuning the 2nd set of voices).
Here’s a quick demo I knocked up. It’s raw SX500 except for some delay (even the best analogue synths can sound a bit lifeless without effects). I think it sounds rather fine!
Apparently when the unit was shipped, the SSM filter chip was tweaked to tame its resonance. Presumably the engineers believed that extreme resonance settings weren’t good for realistic sounds, which is clearly what this was aimed at (check out the list of preset patches printed on the top of the unit). Luckily there is a pot which can be tweaked inside which will restore the SSM chip to it’s screaming former glory. More details on the pot tweak here.
One of the nice aspects of the unit is that every parameter is controllable via midi cc#. This gives a good opportunity for control via your DAW. I knocked up a controller for Ableton Max For Live, which if nothing else, should give you a good idea of all the parameter the synth has to offer. Download the SX500 / EX80 controller.
Overall the SX500 / EX80 is far from perfect. The envelopes are really slow, the oscillators are limited in waveforms, it’s not truly polyphonic and some of the features are esoteric by todays standards but it has a definite charm. I think if you can find one, they can be had for very reasonable prices. Definitely worth a punt.