I really love the Fifteen, cool to see these graphs! With the "does the Drive affect EQ", I think it is more that the EQ will affect the character and amount of Drive in this case (and with all the Bassrigs) since the Drive is actually like the channel volume on a tube amp and so the EQ is pushing the power amp emulation harder as you push it rather than the typical input gain that comes before the EQ. That is hard to really show using a noise sweep vs an actual bass signal, the way the EQ will affect which frequencies are getting clipped more. I think that differentiates the Bassrig preamps from most other SVT/B15 preamp options where the Gain is pre-EQ (correct me if I am wrong RE: the Broughton Fliptop for example). That difference is what drew me to the Fifteen when it was first announced while I have avoided other B15-ish pedals.Moving on to the DI OUT:
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The blue line, labeled "everything off" means just that. The cab sim is off, so is the pedal. The output is much lower then, I compensated a bit, also for the "cab sim only" yellow line, where the pedal itself was switched off, but the cab sim switch turned to the 'on' position.
The green line has all the knobs (again, excepting blend) at noon and the cab sim on.
Just because the Morning Glory had me scratching my head for a minute, I did check if raising the Drive knob has a meaningful impact on the EQ:
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...which it does not.
...and here is the EQ once more, but this time with the cab sim activated.
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I am definitely intrigued by the curve you get combining the cab-sim with cranked Bass/Treble- so far I've mostly avoided the cab-sim on my Fifteen, but this curve is promising and something I'll have to fiddle with more (including using the Amp EQ switches so my stage rig isn't too clacky bright and subby).
There is a "sweetness" that I get from the Fifteen at low Drive that I find super addictive- it so far isn't as nice in a rock mix for me as the Super Vintage (the Fifteen kinda blends in where the Super Vintage punches through), but kinda does the tone Magic thing I would want from a device like the Noble for example (even as the Noble obviously has a different EQ topology and no really obvious clipping on tap). The drive character of the Fifteen is surprisingly versatile too because of the interplay of the EQ and Drive (you can definitely get it into a cool "fuzz" territory when you push the Bass and Drive). There are a lot of tones to be found in it for sure despite relatively limited "Amp" controls.

