Something doesn't sound quite right with the Plexi models compared to my reference amps.
On a real Plexi (same with a 2203 with master on 10 for that matter) when I crank the treble and high-ish Presence settings and zero the bass and mids I hear a certain 'squish' when I play hard two or more notes on the higher strings like an open D chord or 7th fret on the G+B strings together.
This does not happen on the AxeFx no matter how I tweak the Power Supply and Pwr Tubs, Power Amp settings.
I have a PPIMV on my 1987x, I can hear this 'squish' with very low PPIMV settings like 1 or when cranked through a load box, so maybe it is something related to the blocking distortion of the phase inverter grids than the power tubes.
If someone with a Plexi/2203 and a Load Box can confirm that would be great.
@FractalAudio I hope your Plexis are not too far away.
EDIT:
settings and clip
View attachment 32599
AxeFX
View attachment 32600
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It's close but still no cigar.
The real amp also feels more dynamic to play, the amp has '72+ metal panel spec (2.7k+0.68, no V2a cap, 100k from 4ohm tap) in case anyone wonders.