This is why you need a Buffer for Harp - SPLIT Demo

SPLIT will make sure that your tone is at his best always.
More info about the pedal:
rodharpeffects...
Gear used in the video:
JT30 - Shure CR
Amplitube 5, Fender Twin Reverb set to edge of breakup.
The transistor booster is a clone of the Electro Harmonix LBP1.
Disclaimer:
The difference between SPLIT and no SPLIT in this video is real. I didn't touched the audio files. I decided to use this transistor booster because of his low input impedance, so the importance of using a buffer can be better appreciated in this scenario. Having said that, when using a Hi-Z dynamic microphone if the pedal (or amp) has an input impedance of 500K or more, the difference is little when using a buffer. Above 1M is negligible on all my amps. This is true only for dynamic microphones (including Shure CMs and CRs). For Crystals and ceramics, you need the highest input impedance possible to avoid tone loss. Crystals and Ceramics are much more sensitive to impedance mismatch.