When it came time to pick a format for my modules, I had a lot of choices: Doepfer's "Eurorack"; "5U"; and so on. I went a bit outside (I do sometimes) and chose PAIA's offering, FracRak.
Maybe because it's about the same physical size as the API 500 "Lunchbox" format; 500 series is a good compromise in size--the knobs aren't super tiny and the panels aren't huge. With Frak or the 500 series you can throw your rig on the front seat of your car without issue, or just get your girlfriend to carry it on her lap? Try doing that with a Moog 55, right?
Or maybe because a PAIA 2700 kit got me into this whole thing to begin with when I was like 12?
Because I spoke to John Simonton in 2005 and he was one of the nicest guys you could ever talk to? Yeh that's it.
OK good news is that Fracrak is pretty cheap n easy for the case and power supply (which using their 9700 universal power supply, could be built as +/-12 or +/- 15).
For non-critical apps I wanted something a bit beefier than PAIAs "wing" 9770 supply. So I whipped up my own drop in replacement for powering FraKracs:
|The clone board--bolt it right into your FrakRac case.....|
|the original PAIA supplied PCB. Super low parts count--them Voltage Regulators are looking shabby.....|
For this power supply you can get more information on my website including gerbers, PDF of schematic and board layout, BOM etc.
OK, If you want something more stable/better for VCO's let's say, I'd suggest sticking to PAIA's 9771 Psup...maybe I will modify the design above for more beef as well....that said I have built this board a few times and have successfully mounted it inside some of my FracRaks. Works.....no magic smoke.
About the board: The cap values are not critical--I have used 1000uF, 2200uF or 1500uF for C3-C4, 470uF or 100uF for C2-C6, left off C1 C5, 100pF for the caps close to the output headers, etc. I mostly use up whatever I have in my junk box that's reasonably close value wise to what's here. Good enough.
If you are a more advanced DIYer and want to get a freebee of this board, personal message me through the electro-music forum (my handle is cslammy). Maybe we can do a swap?
Coming soon: More noise projects with voltage controlled attenuators.