The System 700 Build is Complete

A post long in the coming, I’m announcing that all the electronic work is DONE on my Pharmasonic System 700 clone!

I purchased a Hexinverter Mutant Brain to function as the MIDI-to-CV input for the synth and also picked up a black faceplate for the 4MS SISM so it wall match the rest of the system. My spring reverb kit arrived and I was able to assemble it the same day, and frankly sounds great. The spring tank is larger than I expected, and I don’t think it will fit nicely in the back of the case as I had planned. I’m going to do some measuring and thinking about this, but it may need to be mounted on the inside of the case’s back panel instead, or alternately in its own case. As the springs pick up electrical interference easily, a separate case may be the best option for sound quality.

I also touched up any ‘slippery’ jacks on the modules, as several were failing to hold cables that were jacked into them. This was due to extra pressure I was putting on the jacks when they were screwed into the faceplates, and the issue is fixable by reheating the jack’s pins on the PCB’s and re-setting them in their holes.

Finally, one of the 2 envelopes on the dual envelope module was not providing an “Release” function, regardless of its release knob. I went to a local electronics meetup last night and got some help diagnosing the problem– which turned out to be a nut I’d soldered between the pot and the board somehow, and was naturally shorting out the pot. It took all of 10 seconds to remove the nut and have a fully working module.

This has actually given me a chance to PLAY the synth, and it sounds amazing. One of the VCO’s goes out of tune when the system is started up, but comes into tune within a couple minutes, and otherwise the system displays no other problems or foibles.

I feel like I’ve just scratched the surface of its capabilities so far with some simple patches, but they still sound impressive! The VCO’s are lush and full sounding, with what sounds to my ears what a real Roland should sound like. The filters are capable and flexible. The modules’ CV and inputs are plentiful enough that there is often little need for mixing signals outside of the modules, which is very nice and cuts down on the need for lots of utility modules for this task.

In the meantime, I’ve started work on the Weston Audio 2VL1 modules. The project is very well documented and has been straightforward so far. I’ve managed to build out 1 of the 3 boards of each VCO so far.

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