The raw Crumar Bit in a proper suit

I am starting this new blog spantaneously with a short praise of one 80s DCO polysynth which is commonly regarded as the ugly grey duckling: the Bit family by Crumar. I think the main reason for the lack of popularity today is the bad user control, i.e. typical mid 80s parameter select-and-change that you also find on the DX7, JX8P, SX240 and many more. And - with the notable exception of the Juno series - DCO synths are in general regarded as less interesting (musically and as collectibles) compared to VCO synths. Is there a development branch of new DCO polysynths for the high end synth buyer?  

I think DCO is cool and my shining example is the Bit as a kind of poor man's version of the ELKA Synthex. Its DCO architecture is something worth coming back to for exploration. It is special and a lot different from other DCO synths. It is such that it makes the Bit a characterful instrument rather than a piece of precision electronics. To be concrete: the pitch bend and tune (and detune!) are hardware implemented in the Bit and operate directly on the master DCO clock source! The clock source itself is not a (super stable) crystal but it is a flip-flop type circuit. And finally, the ramp waveform is not generated from classic integration (as in the Roland machines) but are created by summing up digitally divided pulse waveforms by using bit counter chips. All quite creative, although largely copied from the ideas of Mario Maggi which you can find in the ELKA Synthex. Still, the basic sound of the Bit oscillators is sublime and unique, the handling of pitch is immediate and raw. Surely this is could be worth a shot for a new polysynth without the massive effort and complexity of the Synthex?

Unexplored spaces in the DCO universe

Many of the more desirable vintage DCO polysynths have specific strengths but almost all of them have flaws and shortcomings - including the Bit (very much so, actually). Take the popular JX8P for example: it has great patch options (cross-modulation, envelope routing, velocity), yet its too perfect sounding DCOs and too soft filter unit can make it a very sterile experience (it has its own merits which I appreciate). There are many more examples where basic DCO concepts were not really brought to full bloom. It seems that the market moved too fast at the time and then died the "DX7 death" when R&D budgets went elsewhere before all the great ideas and concepts had time to consolidate into something bigger.

My vision would be a simple DCO synth with the outstanding qualities of the Bit, in particular with hardware tune and detune but combined with proven features from other synths such as cross-modulation and PWM. Or, looking at it from the opposite side, a JX8P with a characterful sound and a 24db filter with more grit - and some more gaps filled in.

In this blog I intend to examine DCO synths and the ciruitry used. I will also experiment with DCO circuits and share my findings and ideas.