DSP TO TAME THE BASS IN HARBETH SPEAKERS

to tame the bass bloat in my Harbeths when driven by tube amps

Sounds to me like its nothing to do with the speakers, or the room, and DSP certainly is not the answer. You're trying to make your tube amps have the same thin unsatisfying bass as solid state. I have a better solution: get used to it. If anything maybe try and figure out how to find SS amps that have as good bass as your tube amps. 

I know. But you can always try.

DEQX

to tame the bass bloat in my Harbeths when driven by tube amps

What amplifier and what Harbeth? This might be solved in a simpler fashion!

You know, you don't need DSP per se for this.  The Schiit Loki would probably work for you too, without an A/D , D/A conversion step.

Proper room treatment though is always good. 

You need to see my other discussions for my complete set up - I've been through all the alternatives... and... have found the solutions.  At this point, I'm just wanting to know the best DSPs to resolve bass bloat (which is primarily the result of room issues and secondarily related to the more limited control by tube amps)....