Friday, August 3, 2012

Ring Modulator

I recently took another look at this module and did some more adjustments to it,  the following blog was written during an in between stage.  You may want to look ahead in my blog for a more current version of this build.

I bought a passive ring modulator kit from Synthrotek.

It worked ok, but I didn't like how much it attenuated the signal (decreased its volume). So I thought it would be cool to build a circuit that boost the signals going into the ring modulator.

The ring modulator kind of works like this.  There are 3 jacks--the first is the input, the second is the carrier and the third is the output.  something magical happens between the input and the carrier whilst in that ring of diodes that creates a bunch of kooky shit and it sounds cool, or at least it's supposed too. I'm not sure, it may be the transformers in there, but you loose a bunch of volume somewhere along the line, and all can hear is some crinkly ghost sounds by the end.

So, I built a signal boost circuit using two LM741 op amp chips.

Here's my super simple circuit.  It's a basic non-inverting amplifier.  Unlike the non-inverting averaging amplifier in my simple mixer, this one has a 50k potentiometer to control the the amount of amplification.  I think the spread works out to be a gain of between 2x and 51x.

I made two of these little circuits and put them on a perf board, one for Input signal and one for the carrier signal.  I forgot to take a picture of it all soldered up, but anyway...

Here's what it looks like as a module from the side.

Here's what it looks like from above. you can see my two potentiometers up there control the volume of each incoming signal, so they can also be used as a kind of mixer or controller--as volume seems to be a factor in how the two signals affect each other.

It was definitely a vast improvement, especially in the bass department. Next time around, I may even try for 100k potentiometers instead of 50k, which may result in the incoming signals clipping after a certain amount of gain, but that might sound cool too.  dig it.


  1. Hi, I'm building a ring mod based on this design and I'm interested in integrating your signal boost modification into it. I'm not entirely sure how I go about doing however. Would you be able to show me some kind of schematic of the two circuits integrated if that's not too much of a massive hassle? Cheers.

  2. Hey, I actually rebuilt my ring modulator module with a different, simpler but better circuit.

  3. Oh nice one, cheers man! Looks simple enough.