Build report: Brett's Modulatron ring mod

[octafish]

After struggling with a "classic" diode ring modulator for a while and not being able to cancel the carrier wave to my satisfaction I decided to give brett's modulatron circuit a try out. Plus seeing all the recent posts on getting the Ring Fronicator working when I had such an easy time building this very effective ring mod prompted me to post a build report. I built it using brett's pcb layout pasted to a piece of pad per hole perfboard as a guide. That made the build quick and easy. Building the board without external wiring took one and a half hours, that is really fast for me. There was only one component I didn't have, the cd4066 chip, which is available in the RS equivalents in Oz. I only made three changes to Brett's design.


First, I substituted 270n caps for the 220n caps 'cause I couldn't find the 220n's that I knew I had around here somewhere. Yep found them right after I finished.
Second I added a line in for a carrier wave using a mono switching jack, because, well why have a ring modulator if your not going to make weirdness? and whats weirder than modulating your guitar signal with a talk radio station, or a casio keyboard demo song.
Third, I made the nulling trimpot an external pot because I would be feeding different signals into the carrier.

I had considered buying an expensive chip to build a proper ring mod if this didn't work but i won't be buying an ad633 anytime soon. This thing plays great. A little bit of carrier signal sneaks through but it's a lot less than with my diode tranformer monster. I think a diy noise gate should fix this without harming sustain too badly,(should be less than the level I need for piezo pickups). The Modulatron is a lot cleaner in its clangs and daleknations than with the diodes as well, but if I ever need the fuzzyness of the diodes a mild fuzz post modulator should get the same effect.
One day, when I can justify the money spent on such a weird and seldom used effect, I'd like to buy a commercial ring mod, (read this subliminally: frostwave, frostwave, frostwave, buy Australian) but until that day I'll be very happy with this (Australian designed) diy alternative.

Its here.

http://www.members.optusnet.com.au/~jethro.dog/gallery.html
This build should provide less hassles than diodes and transformers, and actually cost me less than my passive ring mod did.
edit: spelling

P.S. I have had this thingy running for a week now and think I am over the "honeymoon" phase. Also coming soon a build report on a FY-2 with built in booster (when I stop tweaking it).

[Paul Perry (Frostwave)]

And here's another Australian Ring Mod:
http://www.cgs.synth.net/modules/cgsrr.html

It's Ken Stone's passive, which he sells fro $30 assembled (contains four hand matched germanium diodes).
He sells plenty of bare PCBs for various synth modules (mostly +-12v though). The passive ring mod is only available assembled, though. But there is enough info there to DIY, if you feel up to matching the diodes.

[octafish]

That is a very reasonable price for matched ge diodes, plus a compact pcb and two transformers (they look like the DSE/Jaycar ones I used). My matched set was closely, but not perfectly matched from a pool of 20 or so IN60s and I still got a heap more carrier wave leakage than the modulatron. Ring mods are my favorite effect to play with but I just can't seem to find an actual use for them in live/band situations.

[Transmogrifox]

Radiohead finds some good uses for ring modulators.  Granted they aren't being used constantly on every song like effects such as distortion and delays, but that's a band that will give you good ideas of how to use it in a live setting.

Check out my thread on the yaya effect.  That can be accomplished with a high-Q filter (like Mutron and similar) and a ring mod if you're at all interested in the vocal "ye, yah, yaya" sound.  I have a sound sample of it posted there.