Awesome mod, wondering if you’ve considered adding a CV input at all instead of the potentiometer? I’m guessing the rest of those IC pins controls the rest of the sounds, I’m now sizing up top panel real estate!
That’s a great idea! If I were to re-do this project today I would probably do that. (I had thought about using the Arduino to control the oscillators, but I didn’t have enough analog pins available and wanted the immediacy and tactile feedback of knobs.)
@@charleswerbick2154 I’m actually wondering if a modular synth can be used to control it, so a square wave tapped directly from a modular system, using the PWM knob to see if it can get close enough to the 20ms needed. Attenuate as necessary to ensure no fried chips…Or am I missing something?
super sick dude. Im planning on getting one of these soon & modding the hell out of it 🙂 btw, do you know if an adjustable clock replacement is possible with the 626? i know the on 505 you can replace the global crystal clock w/ an LTC1799, but i can’t find anything about ppl doing the same with the 626
Thanks! You probably could hack the master clock. the TR-500 and the. TR-626 are very similar and a lot of the mods for one will work for the other. (The circuit from this video is 4x VCOs so it's similar but I'm hacking the clocks per channel instead of going at the master.) If you do decide to mod any of these old TRs, good luck and be extremely careful soldering! (and do your mods incrementally, then test the sounds after each mod) It's pretty easy to "perma-bend" one and they do not sound good once that happens.
@@charleswerbick2154 Thanks for the response! Yeah I just ordered a ROM expansion kit from HKA Designs, so I was planning on installing that & doing some bending as well. Id really love to have complete pitch control over each channel but it does seem a little delicate & intimidating… And i’m not really sure how it would interface with the ROM expansion either. I haven’t found any info regarding that online so… 🤷♂️ I may just stick with the ROM expansion & maybe a patch bay for data channel bends. And I appreciate the cautionary advice, irreversible damage is definitely something I want to avoid lol
I believe that you can pull one of the legs off X2 and use an LTC, that's what I'm planning to do with mine, in addition to hopefully these mods (which are great).
Any chance you have a drawn schematic of any kind of your circuit? It seems simple, but the values are probably important, and the diode/resistor portion for the duty cycle isn't something I'm familiar with.
I just bought a TR626 and I'm quite interested in this mod but I've got a lot of SMD soldering practice before I even attempt it. Could you potentially do another video of just playing a normal rhythm pattern on the Roland and just playing with the knobs from this mod? I want to get a better sense of how it sounds.
Awesome mod, wondering if you’ve considered adding a CV input at all instead of the potentiometer? I’m guessing the rest of those IC pins controls the rest of the sounds, I’m now sizing up top panel real estate!
That’s a great idea! If I were to re-do this project today I would probably do that. (I had thought about using the Arduino to control the oscillators, but I didn’t have enough analog pins available and wanted the immediacy and tactile feedback of knobs.)
@@charleswerbick2154 I’m actually wondering if a modular synth can be used to control it, so a square wave tapped directly from a modular system, using the PWM knob to see if it can get close enough to the 20ms needed. Attenuate as necessary to ensure no fried chips…Or am I missing something?
super sick dude. Im planning on getting one of these soon & modding the hell out of it 🙂
btw, do you know if an adjustable clock replacement is possible with the 626? i know the on 505 you can replace the global crystal clock w/ an LTC1799, but i can’t find anything about ppl doing the same with the 626
Thanks! You probably could hack the master clock. the TR-500 and the. TR-626 are very similar and a lot of the mods for one will work for the other. (The circuit from this video is 4x VCOs so it's similar but I'm hacking the clocks per channel instead of going at the master.)
If you do decide to mod any of these old TRs, good luck and be extremely careful soldering! (and do your mods incrementally, then test the sounds after each mod) It's pretty easy to "perma-bend" one and they do not sound good once that happens.
@@charleswerbick2154 Thanks for the response!
Yeah I just ordered a ROM expansion kit from HKA Designs, so I was planning on installing that & doing some bending as well. Id really love to have complete pitch control over each channel but it does seem a little delicate & intimidating… And i’m not really sure how it would interface with the ROM expansion either. I haven’t found any info regarding that online so… 🤷♂️
I may just stick with the ROM expansion & maybe a patch bay for data channel bends. And I appreciate the cautionary advice, irreversible damage is definitely something I want to avoid lol
I believe that you can pull one of the legs off X2 and use an LTC, that's what I'm planning to do with mine, in addition to hopefully these mods (which are great).
Any chance you have a drawn schematic of any kind of your circuit? It seems simple, but the values are probably important, and the diode/resistor portion for the duty cycle isn't something I'm familiar with.
Do you mean this circuit?
cdn.hackaday.io/images/3882461435044432252.jpg
(From the project page on Hackaday - hackaday.io/project/6389 )
@@charleswerbick2154 looks good, yup. thank you
Wouldn't it have been easier (at 4:26) to cut the traces midway and solder directly onto them?
Possibly. But either way the penalty for a mistake is high. (One way I've got a broken pin, the other I've cut the wrong trace accidentally...)
I just bought a TR626 and I'm quite interested in this mod but I've got a lot of SMD soldering practice before I even attempt it.
Could you potentially do another video of just playing a normal rhythm pattern on the Roland and just playing with the knobs from this mod?
I want to get a better sense of how it sounds.
did you see this one yet? - ruclips.net/video/nu6FfKYgT78/видео.html
Must have missed it somehow.
Cheers.