- Replace the R9 resistor from 10K to 18K (or more), to balance the on and off stomp volume. I've choose 18K.
- Add a on-off-on toggle switch to select the C4 values (or no C4), this will make a subdued, but perceptive, diference in the effect tone. The middle position will select none capacitor, the Boss TR1 came originally with 0,1uF cap and the Behringer came with a 0,68uF eletrolitic cap. You can select 0,1uF, 0,68uF and none capacitor, or try out others values.
See the picture:
*Use Boss schematic above to mod this Behringer stomp box.