From heja@neuroinformatik.ruhr-uni-bochum.deFri Nov 17 10:32:58 1995 Date: Fri, 17 Nov 95 12:25:52 +0100 From: Herbert Janssen To: electronica+@andrew.cmu.edu Subject: Re: D-50? Hi, Damien Miller wrote: > What is the architecture of the D-50? I am interested in a cheap (non > -FM) digital synth, how tweakable is it? The D-50 has a somewhat strange architecture. It is 16 voice polyphonic in "single" mode which means 2 oscillators per voice, or 8 voice poly for 4 osc patches. Basically bitimbral, although then you can use only 2 oscs per voice. There was a third party extension to make it multitimbral though. The basic setup per oscillator is either synth: saw/sqr-osc -> lowpass -> amp or PCM: sample-osc -> amp That means you can either use a nice analog style oscillator with saw or square waveforms plus a good sounding lowpass (with a resonance parameter, but the resonance isn't shifting with the cutoff) or a sample playback osc with an amp stage only. The "synth" type oscillators offer waveform modulation as well, i.e. PWM for the square waveform and "slope modulation" for the sawtooth. Two of these sections can be combined in a number of "structures": additively, i.e. PCM+synth, synth+synth, ... but also including ringmodulation. After that you have a 2 band EQ with adjustable freqs and Q for the high band (very useful) and an FX unit which produces chorus and some variants (flanger etc). Note that there is one chorus/EQ per 2-osc section (i.e. 2 overall) which is a little weird but actually useful. After that you get a quite nice reverb/delay which can even load new algorithms via MIDI. The modulation is a little fixed but quite good: 3 LFOs + 3 Envs per Tone, can be routed to pulsewidth, filter and amp. The envs are "dedicated", the LFOs (almost) freely assignable. There are enough mod destinations for seriously warping The PCM section is much more limited here, you can't even use the LFOs for tremolo. As you will probably have heard already the D-50 is notorious for its looped waveform sequences as in the infamous "Digital Native Dance". I don't like those very much, but the good thing of having only little sample storage and no multisampling available is that they put some interesting attack transients and short loops into the ROMs. Good for synth programming (breathy, metallic sounds) and of course bad for piano etc. Also has portamento and repeat feature that plays the sections with adjustable delays. Overall the sound is very soft, I would say that the sound is what makes this synth interesting even today. The user interface is absolutely horrible because many parameters interact in unusual ways. At first, I wasn't able to program a simple saw pad after several hours with the manual. I use editing software now, and that makes programming a breeze. If you spend a lot of time with the machine though, it is probably rather straightforward to operate. MIDI response is slow, there is another third party upgrade to fix that. And the joystick is not too useful (zipper noise, not assignable and always is disabled after switching patches). Then there is that awful Roland "bender". But this is a matter of taste maybe. Bottom line concerning programmability: fairly good, certainly doesn't (need to) live on a bag of gosh-wow ROM-samples. Don't get me wrong with all that criticism, I like the thing. ;-) ciao Herbert P.S. Forgive me that I din't use the Roland speak of Tone/Patch/Partial above, but I always mix these terms up since they aren't even consistently used by Roland themself.