Members bruto Posted March 15, 2007 Members Share Posted March 15, 2007 bruto, you do love digging up old threads, don't you?!! i don't mind, it's one of the few threads I've ever started on here!! Well, it's a great thread, and there's no reason to re-invent the wheel. It's too bad about Wiki being so far off track on the DCO article. Some people are just proudly ignorant. BTW, if you want to read a good Wikipedia article, read this: http://en.wikipedia.org/wiki/Matsumoku I'm obviously a little biased here as I wrote it (aka PioGraphica.) The Casino at the bottom of the page is mine. The red Aria on top belongs to a friend of mine. Link to comment Share on other sites More sharing options...
Members Rouqmirg Posted March 15, 2007 Members Share Posted March 15, 2007 To further the discussion a bit: Once you get to the point of having an ultra stable VCO (such as what is supposedly used in the Little Phatty), what is the advantage over a DCO, or even a digital oscillator? If the 'analog sound' is a product of pitch drift, and varying start phases, why should a DCO sound any better than a pure digital oscillator that varies the start phase? Why should an 'ultra-stable' vco sound any better than a DCO? I know, I'm neglecting the filter, but let's talk pure oscs first. Link to comment Share on other sites More sharing options...
Members mildbill Posted March 15, 2007 Members Share Posted March 15, 2007 ....A DCO is an analog oscillator using a digital clock for stability..... This is my understanding too. What I have a question about (not soon to be answered, I suppose), is this: Can the analog oscillator part be identical in the 2 types. In other words, can you take an 'xyz' oscillator, and then put it under 'voltage control' to get a VCO; and then take the exact same 'xyz' oscillator and put it under 'digital control' to get a DCO? Seems to make perfect sense to me, but I don't know of any examples. Link to comment Share on other sites More sharing options...
Members Metrosonus Posted March 15, 2007 Members Share Posted March 15, 2007 In regards to the poly 800, Im going to say that it uses samples based off a clock. The 800 is unique beause you can select the length of the wave you want to use: 2,4,8,16 in any combination. My guess would be that this is easy to accomplish if you use samples, if not each oscilator must be made out of 4 different oscilators. When unison is turned on, the 800 emulates a saw wave by staggering each wave into a rough saw shape. This would be easy to do with samples.. which is my guess. I just dont think a 2 voice synth made out of 4 oscilators a piece would have been the entry level product korg intended IMHO.. Link to comment Share on other sites More sharing options...
Members ChipCurtis Posted March 15, 2007 Author Members Share Posted March 15, 2007 This is my understanding too. What I have a question about (not soon to be answered, I suppose), is this: Can the analog oscillator part be identical in the 2 types. In other words, can you take an 'xyz' oscillator, and then put it under 'voltage control' to get a VCO; and then take the exact same 'xyz' oscillator and put it under 'digital control' to get a DCO? Seems to make perfect sense to me, but I don't know of any examples. No, VCOs and DCOs are not interchangeable based on some possible hardware hack (you'd have to reconstruct the whole oscillator to do so). The issue is that the core of those two different oscillators is completely different. Both involve analog waveshaping after the core, and both are analog oscillators, but the DCO's core is nothing but software that emits a pulse-wave-train, whereas the core of a VCO is an electronic oscillation based on control voltages. Obviously the latter is going to involve some pitch instability, which is the hallmark characteristic of VCOs. Link to comment Share on other sites More sharing options...
Members ChipCurtis Posted March 15, 2007 Author Members Share Posted March 15, 2007 In regards to the poly 800, Im going to say that it uses samples based off a clock. The 800 is unique beause you can select the length of the wave you want to use: 2,4,8,16 in any combination. My guess would be that this is easy to accomplish if you use samples, if not each oscilator must be made out of 4 different oscilators. When unison is turned on, the 800 emulates a saw wave by staggering each wave into a rough saw shape. This would be easy to do with samples.. which is my guess. I just dont think a 2 voice synth made out of 4 oscilators a piece would have been the entry level product korg intended IMHO.. Yes, I suspect what you are saying about the Poly 800 is correct. I think at its core it is nothing more than sampled single-cycle square waves, and this becomes the pulse-train to drive the DCO rather than software emitting a pulse-train into an analog waveshaper. Yes, it then creates the sawtooth wave by staggering square waves into a rough saw shape as you said. This is all done digitally. Since the Poly 800 "DCO" does not have analog waveshaping like the Juno/JX oscillator does, it is in fact a pure digital oscillator and not a real DCO. Many have commented that this is why the Poly 800 always seems to have a square-wavish sound to it, no matter what waveform you select. Link to comment Share on other sites More sharing options...
Members Metrosonus Posted March 15, 2007 Members Share Posted March 15, 2007 Thats the main reason I love it. I love square waves and the saw has a nice edge to it. People call it the little brother of the dW8000 (which I love as well) but I think that's incorect. It has to much of its own uniqueness to be call a downgraded version. Link to comment Share on other sites More sharing options...
Members mildbill Posted March 15, 2007 Members Share Posted March 15, 2007 .... both are analog oscillators, but the DCO's core is nothing but software .... That statement is not my understanding, but I don't know too much about it .I am pretty sure that analog oscillators aren't built up in software tho - those are digital oscillators. Link to comment Share on other sites More sharing options...
Members pighood Posted March 15, 2007 Members Share Posted March 15, 2007 A bit of heresy for y'all: I LOVE DIGITAL AS MUCH AS I HATE ACAPELLA. Link to comment Share on other sites More sharing options...
Members mildbill Posted March 15, 2007 Members Share Posted March 15, 2007 I like digital stuff too. Link to comment Share on other sites More sharing options...
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