Here’s a PCB and Layout for the Ring Modu-Matic. I have yet to build this yet so use these files at your own risk! The dual gang pot in the lower corner I can’t get rid of, due to my lack of skills with Eagle. Notice the lines connecting the pot to pads on the PCB.

*** edit: These schematic and PCB had some errors. It’s been removed. There is an updated version the next post ***

This is a first draft of an idea that I have been thinking about for a few months. It’s a Tremolo that pans between the input signal and the signal coming through the FX Loop. If no signal is coming in to the FX Loop it would act as a normal Tremolo. Otherwise it would be cycling from the straight to the effected signal.

The main idea was taking from Nicolas Boscorelli’s Stompboxology Tremolo-Matic X. I make no gaurantees that this actually works as I haven’t built it. This is just a first pass to get the idea down.

This is Tremolo-Matic X from the Tremolo Issue of Stompboxology by Nicolas Boscorelli. I have redrawn the schematic to make it easier to read. Hopefully this will be helpful to anyone attempting this project. This is Tremolo that pans between a treble and bass signal. It inlcudes controls to set the level for both the bass and treble, rate and depth.

I built mine from the PCB layout posted by Morocotopo at Diystompboxes here. This lay out worked well for me. Though it looks likes it isn’t finished as there are a few extra pads that don’t quite make sense. The layout does work. I have built it myself.

It sounds pretty good. I made a few changes. First I changed the Rate pot to 100K to get a more useable range of speeds. With the original 25K pot the slowest speed was not very slow. I like the sound of slow tremolo. The 100K pot is shown on my vsersion of the schematic. speaking of the rate, I’d like to get a slightly faster rate at the fast speed and a little slower at the slow end. I think I will be playing with R21, R25 and C15 a little more.

The other mod, not included in my schematic, is to decrease the gain on the input stage. Basically this comes down to decreasing the value of R14. With the original value of 470K you get a little bit of clipping with hot pickups. I haven’t decided on a value yet.

Note the, input stage is inverting. Which presents a lower input impedance than would normally be acceptable. But it seems to work OK here.

Also note that there are a few parts list as optional feed through bias or something like that. These parts include a 5V regulator and adjacent parts. I left these out of my build, and everything worked fine. I left these out of the schematic posted here.

This is the Ring Modu-Matic from Stompboxology. I redrew everything in Eagle PCB. This is an interesting design. It seems to use several different supply voltages. There is a +9v, +4.5v and +5v, +2.5v,