Boost switch question, cap/resistor order (Vox UL/Hybrid 7-series preamp)

[seven]

I'm playing a guitar with P90s through it.

[seven]

So, an update to the update.

I tacked a 0.022 across C28 and noticed a subtle, but discernable change in brightness.

I want to presume that I have it wired it up correctly but will double check anyway.

I was using a power amp/speaker setup possibly more voiced for E. bass so that could be the reason why it wasn't perceptible with the stock 0.0022 value?

[Helmholtz]

I'd expect some treble boost above maybe 3kHz.