Huh? My fuzz's output tone brightens when I reduce treble coming from guitar

[bipedal]

Wondering if anyone can shed some light on this behavior, which I've noticed only when playing through my germanium Fuzz Face clone (Mayer mods).

What happens:  I've noticed that at higher fuzz settings, the output tone actually seems to brighten up and gain clarity when I roll down the tone control (reduce treble) on my Telecaster...

My guess:  the guitar's tone control impacts guitar's output impedance (impedance reduces as tone is rolled off?), which is interacting with the fuzz circuit.  As output signal impedance is lowered relative to pedal's input impedance, more of signal's top end is preserved.   

Am I on the right track?  (And is that typical behavior for a Fuzz Face type of circuit?)

Cheers,

Jay

[brett]

Hi
yes, it is normal for the treble roll-off of a FF to reduce when the volume (and possibly the tone) controls are turned down.  The output impedance of pickups is high relative to the input impedance of a FF.  The pickups are also very inductive and capacitive, and the guitar lead also has significant capacitance, all of which increase the roll-off.  A short, good quality guitar lead helps (20pF per foot instead of 40 or 50pF per foot).  Alternatively, consider the loss of highs a good thing and buy a cheap, long, curly lead.  I think some guy called Jimi did that, and it worked for him. 
cheers