English Enigma:
Those pedals aren't true by-pass. Putting anything that isn't true by-pass in the signal chain can degrade the sound (volume loss, loss of highs, added noise). You can either buy pedals that are true by-pass or get yourself a Tonebone Looper (
www.tonebone.com). The looper is a by-pass. It takes the pedals out of the signal chain when they're not in use.
Good luck,
Robjabber