Lo-d (Hitachi) Vintage Analogue Synthesizer HMS-30

via this auction

"I have never seen one of these synths before, and there is very little info on the internet about it. Seems to be a rarity. Made sometime around the start of the 80's by Lo-D, which seems to be an offshoot of Hitachi in Japan. Reasonably large and well built machine, with classic wooden panels from the vintage era.

Here's what i have observed:
it is FULLY POLYPHONIC. not 4 or 6 or 8 voice polyphonic, but 100% polyphonic. Every key produces a note.

Each voice consists of 2 layers:
a sustained wave for the body of the sound, and an enveloped wave for the dynamic attack of the sound. each of these layers has the following 8 controls:
filter cutoff, filter resonance, pan, volume, warble speed and depth, tremolo speed and depth.
('warble' is an LFO which modulates the filter cutoff.)

so, basically, you build the sound from 2 layers, which are mixed together. each layer has its own filter and modulation options, and can be panned, so you can make nice stereo by putting one part to the left and the other to the right.

There is a global LFO for vibrato on the pitch. Rate and Depth can be altered with knobs. Total pitch can also be quite significantly altered using a knob which sweeps from bass right up to very high tones.

As if that's not enough, there is also a built-in rhythm machine, which consists of various simple drum patterns and a simple analogue drum engine which makes some simple bass, kick, hihat sounds. Certainly not going to replace you

So, a quick roundup so far of what this baby contains:

5 LFO's (global pitch, plus tremolo and warble for each of the 2 layers), 2 VCF's, One VCA, and a drum machine.

For an early 80's machine, that stuff by itself is pretty cool, but it seems to have gone a fair bit further than that with a whole section of buttons for controlling and editing an inbuilt sequencer. The LED's on that section are sadly not lighting up anymore, so one can only wonder to the full capabilities of this synth. I'm guessing it would have been quite expensive with all these options. The build is also very nice. The keyboard volume seems to change at a point 2 octaves up the keyboard. I assume this is to keep the volume of bass a bit lower than the melody when playing."