Date: Fri, 20 Aug 1999 00:09:33 -0700 From: SuperBad MoFo Subject: Why don't people listen to 303s before declaring themselves 303 experts? Ah yes, AH's Quarterly 303 FlameWar, right on schedule. Don your flame retardant suits! At 12:51 PM 8/20/95, Ian K Tindale wrote: >Scott Koladich privately tells me that: > >>The Accent feature is virtually the same as the 303. At 6:13 AM 8/20/95, Ernest Bruggeman wrote: >I believe the 303's accent only sets the >decay to max. At 11:00 AM 8/20/95, Matt Haines wrote: >accent: wacks the filter, resonance and vca all at once. The 202 just wacks >the VCA. BZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZzzzzzztZZtZZTtztztttt...little puffs of smoke... Ok guys, you've all demonstrated that you either: 1) haven't listened to a 303 OR 2) don't know enough about how changes in filter cutoff and resonance affect a sound to make an informed statement on the subject. I'm forwarding you all a thread from the annals of AH entitled "Secrets of the TB-303", in which a guy named ERIK describes how he listened CLOSELY to a 303, and what he was able to discern based on his observations. Read closely - you may learn how to listen. Anyway, here's the executive summary, excerpted from my letter printed in Keybored a few months back: According to the 303 service docs, Accent modulates the Resonance amount and the VCA, not the Filter Cutoff and Envelope Decay as stated by Vail. What makes the 303 unique amongst non-modulars is that the Envelope positively, then negatively modulates the Filter Cutoff (it's bipolar). These features are undoubtedly responsible for the 303's "squelchiness" >The 202 (and the 101) seem to have similar filters to the 303, but there's >differences that perhaps others could assay. I had my 101 sounding very >303ish a few days ago, especially when I tweaked the res in realtime to >simulate accents. The 101/202 will self-oscilalte though, whereas the 303 >doesn't seem to quite get that far. > icu> Is the 202 modifiable to do it as well? Does anyone have > icu> access to the circuit diagrams for the 202? Help me turn mine into > icu> something completely different! Don't have 202 schematics, but given that some 202s sound _just_ like some 101s (those 101s & 202s were a very inconsistent lot), I'd say they use the Roland IR3109 filter. This is OTA based. The 303 uses a modified diode ladder (transistors hooked up to act like diodes). The 303 filter won't oscillate - the poles are in the wrong place. My theory is that high amounts of resonance make the filter distort, causing that characteristic, unduplicated "shredding" sound. If you REALLY into it, you could probably modify the "gimmick" circuit from the 303 filter to work w/ the 202, to modulate the cutoff, maybe jack up the gain of the filter input to make it clip, but trust me, acid afficionados will probably still be able to hear the difference. >>The slide, however, is >>different on the 202, but, in my opinion, much more versatile. The slide on >>the 303 slides so you hear the whole slide, but the 202 is like classic >>portamento, in which sometimes the target note might not be reached, which >>can make some really cool effects. I find the 303 slide to be more useful. Since it's not "classic portamento", it sounds different from any other synth I own. The 303 is "constant time" portamento - the time it takes to get from a low note to a high note is the same as the time to slide between adjacent notes. The 202 is "constant rate" portamento - which is why sometimes the target note isn't reached. >So, (guesswork mode) if the 303 glide <...> > Does that sound right? Actually, I never have quite figured out how the 303 portamento circuit works. It's composed of a 4066 CMOS switch and some capacitors...I'll have to get back to you on this. At 11:00 AM 8/20/95, Matt Haines wrote: >Yet, when you trigger a 303 with cv/gate input (mine was >modified to do so, but it's gone and I want one back), it sounds like a >lame single-oscillator synth. Filter and resonance not withstanding. (So >flame me, it's true). No need to flame - you're absolutely right on this. The 303 is a pretty undistinguished monosynth w/o the funky accent & slide stuff. At 11:28 AM 8/20/95, rbcIII the lovebot wrote: At 6:29 PM 8/20/95, Scott Koladich wrote: >I can get a perfect 303 squelch-y sound out of my 101 How many times have I heard that? >I never understood why the 303 caught on and the 202 didn't. If you can't hear the difference between a 101, 202, and 303, then it's no bloody wonder. FLAMEOUT MR-808