Yes, you are looking at this correctly. In the "normal" switch position you have ;(SW4A) 470pf treble (& upper mid) cap, (SW4B) 33k "slope" resistance
(SW4C) 0.022uf mid cap
In the "mid scooped" switch position you have;
(SW4A) 235pf treble cap (let's less upper mids through).
(SW4B) 99k slope resistance (greater seperation of the treble frequencies & mid/bass frequencies.
(SW4C) 0.011uf mid cap (let's less lower mids through).
It's a pity the Jackson cab only offers
Stereo, 2 X 8 ohms, &
Mono, 1 X 4 ohms
& doesn't have the mono 1 X 16 ohm option like the Marshall cabs do, as you can only use two speakers at 8 ohms leaving two speakers unused.
I would check the impedance of the speakers used in the cab. If it is fitted with 16 ohm speakers it would be possible to fit the Marshall Stereo/Mono Jack Plate that Chilli showed earlier, thus allowing the Mono 16 ohm option (all 4 speakers used). The genuine Marshall part No. for this Jack Plate Stereo/Mono Switch is
M-196X-50-01.
It is available from amprepairparts.com,
Part #JP-800.
Hope this helps. Cheers
