No thin was an incorrect choice of words from me, I was just blown away by the +14dB at 15hz 6db is still quite a bit at 30hz IMO, not something I feel is needed for my use case with the Sundara.It's mostly subbass, and information below 15hz is virtually nonexistent in 98% of any audio content anyway, even very bassy tracks. The midbass increase is barely there. At 80hz, for example, there's only a 3db increase in the second setting. At 100hz, you can hardly hear a difference.
"Thinness," or the antithesis of body, is not determined by the bass frequency response, as experienced users would understand. You can test this by using a bass boost for male vocals; mostly, more bass doesn't make his tone any richer, and at some point it just sounds weird/off. Body is more a function of decay and timbre. The Sundara on many amps does sound thin, for sure. On my XLS, it is full-bodied without being bloated. It's natural/transparent, in other words.
I also have a separate midbass setting, but only occassionally use it, because I find it affects vocal clarity and accuracy, though it does fall in line with the Harmon curve. It really depends on the recording.
But thats the beauty of this hobby, we all have different experiences
Ha e you considered using a peak filter instead of a shelf, to lessen the stress on the driver by letting content below say 20hz drop off again?