I have a strange phenomenon going on with a pair of my pedals. I use an EBS Valve Drive as the primary tone shaper in my setup. I really cannot live without it! It's sort of become "my sound"... Anyway, I have a Frantone Thunderhead (low freq. booster) that I've used in the past for "special effect" purposes. When I want an extra deep, thunderous bomb - I can flick on the Thunderhead & blow out some PA subs!!! I've run into a problem, however. When the Frantone is after the Valve Drive in my chain, the Frantone sort of "bogs down". The volume drops about 50% and the tone gets totally washed out... Frantone before the EBS works fine, but I don't like that setup as it creates gain staging problems on down the chain. None of my other dozen or so pedals acts strangely with the Frantone, just the Valve Drive (and the Valve Drive works great with everything else as well). What gives? I guess there is some sort of impedance mismatch going on, but why can't I recreate it with any other pedals? Weird... Anyone else have an odd set of pedals that refuse to work together?