Yesterday I received my second Chosmochorus(left). Knobs and switch are not original, but the rest of it is.  I bought it with plans to hardwire it into a vibrato. Today I chose to use a switch to do the job, therefore adding a bit of versatility. First thing to do was removing the LED(where the switch will later be installed to keep it away from the stomp switch). The LED originally is not held by anything, so the previous owner glued it in place. I tried my best to remove it safely but the poor thing suffered the worst scenario. LED hole was enlarged and switch installed. At that time I noticed the power jack was broken and glued back together crooked. I didn’t bother me and it held fine so I left it like that. Extra guts shot just for the sake of it. You can see the chips were sanded… first boutique pedals some say.

Original Locobox use SPDT(latching) switches. A 3pdt switch does not fit in these pedals(only the EQ has enough space). This one came with a DPDT, which meant I could use this very same one to true bypass it(necessary for this modification) using an old Millenium board that I put toghether when I first started messing with pedals(5 years ago!). In the picture below it’s already wired for millenium bypass.  I found a dual color LED that I decided to use because it has the look of the original(pictured with anode of the color not used snipped). New position of the LED was drilled, and a new plastic holder installed. Wiring was next and millenium bypass was done and working!

Then it was time for the vibrato modification. This consists in placing the 33K resistor under the dual op amp on a switch that either connects or disconnects the dry signal from input to output. And that’s it. After giving it a try, I noticed a volume loss when in vibrato mod(I expected this, having done this modification on a GIG CH-01 chorus which is pretty much the same circuit). A DPDT toggle switch will be necessary to fix this by using the new side to change the value of one resistor in the signal path that will bring a volume boost. When that is done, this post will be updated. Other than that, I’m happy with how it sounds(and looks)!

(UPDATE)

With the use of a DPDT toggle switch, now both chorus and vibrato are unity gain. In this case I needed to lower the value of a resistor instead of removing it completely(like on the GIG chorus I mentioned before). The vibrato is bit brighter than the chorus and it will need further improvement. This was expected because the lowered value resistor that brought the volume of the vibrato up is part of a low pass filter. Now that the volume is up, I’ll just need to switch between two LP filters. For that I need a different value capacitor in the vibrato’s filter to bring the bass up. I need a 3pdt toggle switch for that.  Another update should follow soon. For now I got other stuff to do!

(UPDATE)

I got the 4PDT switch I needed. It was a bit bigger than I anticipated. I had to sand the two bottom corners so it would fit between the pots. I got it all wired up using shielded wire. It looks ‘messy’ but it’s just too crowded from all the wiring. It closed fine though. I have yet to plug it in and try it. I’ve been very busy repairing things for other people.

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