SPL - Pro Audio Blasphemy?

I'm tri-amping with Crown XTi 1002's and a 2002 and going preamp-less (using the gain input control on the Crowns). While I would tend to agree that high-end usually sounds better, I've also have been steadily acquiring a lot ($10k+ and counting) of some Alan Maher Designs electronic noise reduction gear...all that has collectively raised the level of their performance, under my roof anyway, just into high-end territory (I'm sure nicer hifi amps would've been improved by all that even more, of course). I suppose these Crowns may not have the utmost degree of sheer "magic" of timbre that the best amps can have, but it's easily good enough for me and, with AMD, all the attendant qualities like tonal purity, pitch accuracy, resolution, textures and harmonics are so good that I never have the feeling that anything is missing. It's nothing for me to get wrapped up in the performance and the music. What drew me to the XTi's were the pro tools: EQ, Crossovers, digital gain, delay...that way I could ditch my passive crossovers which has been a great step toward better sound here. And, from the beginning for myself, no worries about trying to win the "passive crossover parts" sweepstakes and that let me save a nifty buck or two. Normally, going digital there might sound worse because of the noise, but that as well is what all the AMD is for and it's all sounding rather gorgeous right now to me. The system itself costs well less than all the AMD, but everything here is working together well. If asked, I'm more likely to rave about AMD than the amps in particular, but these pro amps have certainly found a home here. They're not going anywhere anytime soon. The one DIY mod I had to do was to hardwire bypass the Speakon connectors...rather good for allowing buckets of currents through, but detail?...not so much.

Enobenetto, understood about the rail voltages. Looks intriguing to me too. But, if this were easy enough to arrange in a preamp (for the maker's stated advantages), then could this same idea not also be applied to amps...leading to a combo of high-headroom amp/pre in order to get the most from this approach - that would evidently be the logical conclusion, to me. What comes of their efforts seems to bear watching, I would think.

Kirkus & Alpha_gt: Thank you both very much for the edifying clarification here. This has been a curiosity of mine for a little while now, but did not really know where to begin...I think some lights have begun to come on for me! Much appreciated.