Why not disconnect one of the 12" 16-ohm speakers in your 2x12 cab and try the amp at the 16-ohm impedance setting into a 16-ohm speaker load? See if you like the tone.
A 2 x 12 sounds way different (to my ears) when run on just one speaker, 3dB quieter from loss of mutual coupling but also the loss of phase cancellation between the drivers in the treble.
Pete
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