Boss TR2 C4 Mod




Introduction: Boss TR2 C4 Mod

About: Just having some fun with junx and recycling stuff! If you have anything to ask on just about anything, please don't hesitate.

A very simple mod to compensate for the drop in volume on the BOSS TR2 pedal. After the C4 mod, the TR2 sounded a little harsh and a bit rigid ( I am a bit loss of words in terms of describing the sound here). I kind of like the sound. And the perceived drop in volume is not so much distinguishable.

There's a lot of instruction floating around and I just thought this one might also be useful and helpful for those who are visual learners. Kudos for Little_Buster for providing the instruction.

If you have tried this mod, let us know what you think of the new sound or the drop in volume.

Step 1: C4 Mod Materials

(1) Phillips-head screwdriver

(1) Bowl or cup (you don't want to lose any screws)

(1) Pair of small scissors, wire cutters, or nail-clippers.

Step 2: Removing the C4

1. Take the battery out of your pedal, and/or unplug it from a wall outlet adapter.

2. Unscrew the bottom 4 screws from the pedal, and put them in your cup or bowl.

3. Take the bottom panel and plastic covering off underneath that.

4. Pull out the circuit board, keeping in mind you will have to pull out at an angle so the 9v adapter box can slide out of its hole with ease.

5. Locate the larger of 2 small "silvery pillow" objects (capacitators, if you know what they look like) and cut/clip both leads from the circuit board.

6. Tape the C4 inside your pedal somewhere so that you don't lose it. ( In case you decide that you hate a good sounding pedal, you can solder it back in.

7. Put the circuit board back in, replace the plastic cover, screw the bottom panel back in, and you're done!

Step 3: Changing the LED

1. Trace the wire that leads to the LED.

2. Unscrew the little board that holds it.

3. Desolder the LED.

4. Solder in the NEW LED.

5. Mount the little board and screw.

You are done!



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    8 Discussions

    Yo, just did the mod. Totally solves the drop in volume problem. Do you know anything about the PH-3? The drop in volume on it drives me crazy.

    3 replies

    I do not know any issues with regards to drop volume on the PH3. I've been wanting to buy pedal but it it has volume loss when engage I guess I will stay away from it. Anyone else have issues on the PH3 volume loss? Yo, Thanks for the FYI.

    I love the pedal. The volume drop bugs me but you can work around it. I usually just hit my drive when I hit the phaser. If you get one get an expression pedal to go with it. Very much worth it.

    I have the digitech Phaser but love the boss expression pedal feature on the PH3. Searching for one on ebay at the moment. You can try placing a compression pedal on your board just to even out all the volume--see if that one works. Or you can always use an equalizer and slide the volume up a bit.

    Oh yeah, The newer TR-2's dont have the same circuit board as yours, which means they have no C4 capacitor. Cheers, Buster

    2 replies

    Well thanks for the info. I wonder if the newer ones still have the same problem as with the old one trem.

    FYI: If you run a compressor before all your pedals, you wont hear a volume drop when you engage this pedal with the mod.