Yeah I'm curious to hear what Mark says too. I'd have a hard time believing they sound completely identical, but if that's what the man says, he created this amazing unit. I've compared it to: ASW4000, ASW855, F113, F212, G213 and the SubMersive has SO much less mechanical noise, is so clean, and so quick. Everyone gets rialed up woofer speed, and how it doesn't exist, but the SubMersive is faster than the rest. When I play Marcus Miller (awesome bassist!) the SubMersive doesn't blur the notes together like the other subs. I call that speed or fast, maybe the subwoofer guys have another name for it? Anyway, that's why I'm asking about the amplifiers. I'm sure one of them has the most snap of them all, but maybe I'm wrong? On top of how good it sounds, it also has loads of headroom and extension because I've never heard a bad sound come from it, ever.
The biggest factor is that the SubMersive is operating well within its limits and keeping its output consistent over the full dynamic range. The SubMersive also has a smoother and more extended response that couples better into most rooms than many of the subs you mention, so you start with a bit less "bloat" when you start at the plug-n-play point. Grab a UMIK-1, an EQ or Dirac box and start playing with the response shape and expect to destroy some ingrained audiophile folklore in the process. When operating as a single unit, the HP, HP+ & HPi+ use exactly the same amp board & design. The settings we make in the DSP for the SubMersive largely dominate the differences. Until you are pushing maximum limits with the clip light starting to flicker, there's no difference. The HPi+ has more immunity to Voltage sag on the power line, but only if you feed it with 220-240VAC, and actually has less capability if run at 120V.
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