Hi, I’m need to make my MK 114 light organ more sensitive to what I think is a weak input signal. It works fine connected to a radio, but when I connect it to a Lepai 20 watt amplifier (10w per channel) it doesn’t light at all. The input signal is just voice from a microphone, going through a small pre-amp, a ring modulator, then to the main amp. Input to the MK114 is from the speaker output of the main amp. Looking at the circuit diagram, I noticed the 390 resistor at the signal input side of the circuit, could I substitute a small resistor to help the signal? I’d like to avoid buying a bigger amp if possible. Let me know whta you think, thanks. JB