Beware: modify the pedal at your own risk. I take no responsibility for any damage that might occur to your beloved tremolo pedal.
Ok. Disclaimers are done, and you decided to continue reading. Grab some tea/coffee, have a good read, and when ready, have a go.
I won’t write up about how good this tremolo is, this video is a better review than any write up I could put together.
However, the tremolo has what I think is a major of shortcoming, which is that the depth control is inside the unit, with no easy way to adjust and requires you to unscrew the rear of the unit, adjust depth to taste, and so on and so forth…. some pleople won’t mind, but if you are a performing musician, you are more likely to use more than one depth setting, which makes the unit rather impratical for live situations (that is just my opinion)
To get the unit up to scratch would require to have the depth control easily adjustable externally. I found a couple of sites (here and here) that make mention to the desired mod but did not provide further details, so it was time to change that.
Step Zero – what are we doing then?
With the the Babyface tremolo open, placing the footswitch at the bottom (see image below), there are two trimmer pots, one white on the left (level) and one black on the right (depth), which is the one we want to replace by an external pot. This is a CTS 262UR253A trimmer potentiometer, which translates into a 25KΩ CTS 10mm Carbon Trimmer Potentiometer.
So here is what you need to make this modification
I bought all my parts from Bitsbox in the UK… cost including shipping to Australia was still cheaper than buying local, and by a long way.
Step One – open and dismount the unit
This is straigh forward, essentially you want to end with two major parts, the emply enclosure and the circuit board (see images below)
Make sure you put all your knobs, metal rings, screws and covers in a container where they are kept safe while you are doing the mod. It will make the assembly a lot easier later on.
Step Two – remove depth Trimmer Pot
This is kind of the point of no return. Yes, you can solder the trimmer pot back, but if you are here, it means you are pretty committed to do the mod.
Note: make sure you have the appropriate soldering iron for the job. I didn’t and the job was made unnecessarily more difficult because my soldering iron did not have the right tip (the pointy/narrower the better). The same applies for your solder removal tool. Be careful and remove the right (black) trim pot only. you should end up with something like this (please ignore the soldered wires for now), more on that in a minute.
Now it would be a good time to solder your wires, as you won’t have room for maneuver once the new potentiometer is in.
The ilustration below is the diagram for the original trimpot. I have purposedly placed it upsidedown for your easy of reference when soldering the wires and the potentiometer. Note the bigger numbers 1,2,3. we will match these to the new potentiometer later.
So, as per the diagram above, here’s how this translates onto the circuit board, and where you’ll solder your wires.
Step Three – drill the pedal enclosure
This is probably the easiest of all the steps, but here’s where I ran into trouble, so you might want to do things differently.
There are only two physical locations where the pot can be placed. These are marked as locations 1 and 2 on the picture below. This is not an order of prefference (it was for me) but its only so we can identify the location. I chose location 1. I think location 1 makes more sense from a usability point of view as its less likely to mess around with your pedalboard cables. Locaion 1 however, is considerably more difficult to work with. You will want to measure where to place the potentiometer with the PCB and all components in. The final location for you will depend on the size of the potentiometer you got and how comfortably you feel doing this work. Also, if you plan to make any future mods, you might want to select location 2.
IF you selected location 1 just like I did, then good luck to you! This is what I did.
The new 25K potentiometer required a 7mm hole on the enclosure for the potentiomenter shaft. This is not enough given the position of the potentiometer, as you will need to slide in the potentiometer, and then pivot it to place the PCB. I could not place the PCB and then put the potentiometer… but that was me, you might find a better way to do this. Just keep in mind, you might need to drill an 8mm hole, as it will make your life easer.
So back to drilling the enclosure. I’d sugest you place the enclosure in a vise and use some other material to protect it. also if have access to one, use a step drill bit. It will make the drilling a lot easier.
Step Four – solder in the new potentiometer
Once the enclosure is drilled and we have worked out how to put the whole thing together, its time to solder in the new potentiometer. The trick here is how to wire it. The ilustration below presents a more familiar view of a guitar potentiometer, and the appropriate pin numbering.
For the new mini potentiometer, this is no different, so it would be something like this
All that is left now is to position the components on its final location, adjust but not tight all nuts, as this will help keep things in place, and then solder the wires to the right pins on the potentiometer, that is one to one, two to two and three to three.
And that’s it. That’s the mod done.
Step Five – You are done, test your new tremolo.
Before closign the tremolo, make sure you test it.Once the enclosure is drilled and we have worked out how to put the whole thing. The tremolo should work and sound as it did before, but now the efect depth is controlled by the external potentiometer. Aren’t you glad you did this?
Step Six – while you are it…
As you still haven’t closed your tremolo (I hope), why not make the level trimmer pot accessible? All you have to do is to drill a hole in the back cover, make sure is big enough to allow a small screwdriver in. This will allow you to setup the overall efect/boost level.
As this is something you would not adjust often, but maybe during sound check or when setting your pedal board you don’t need to have it as easily accessible as the depth control.
Step Seven – close up and clean up
Here’s the modded pedal.
You can also replace the ugly ass speed knob that ships with it as I did on the photo below. I tried with several colours and models and this I liked the best (gently donated by a Mooer Hustle Drive which now has a blue knob)