Grapevine 2.0 Tone Stack & Knob Question

[MikeMuscarella]

All -
I have a grapevine 2.0 build and am curious about the tone stack in the circuit.   Here's what I'm experiencing:  I find that the tone knob only effects the treble at the extremes of the pot.  When it's all the way down, I get significant roll off.  But once I open it up to about 8:00, there's little change until I get to about 4:00.  Is this normal?

Thanks!
Mike

[MikeMuscarella]

A gentle bump from a noob