Alright, sorry for taking a bit, but I finally got a chance to give these a listen. I'm with OJ, I found the preamps have a big effect on the sound.

I have two setups:
Rega RP6 w/ a Ortolan 2M Black cart
Technics SL-1200 Mark II w/ a Audio Technica AT440MLA cart.

I've ordered these in the order I liked worst to best:

Music hall - pa1.2
The least likable of the bunch by far. Very mid-forward, rather slow not terribly resolving. Very laid-back It was a little muddy and overall just not great. It just kinda a little sad and lifeless.

Schiit Modi
This pre-amp has more bark than bite. it's kinda the opposite of the Music Hall. It's more resolving and quite a bit faster, but unfortunately, it's too fast. It has a lot of attack, but not a lot of sustain and comes off rather thin. It has good punch on the highs and the lows, but the mids are relaxed.

TCC TC-750
This was the biggest surprise. It's a $50 amp from China beloved by reviewers on Amazon. Overall it resolves pretty well with good clarity. Attack and sustain is pretty good, but it's not great. I think wiring it up to a better power supply could make a much bigger difference here and make it sound better than the Rega. Great frequency response throughout, better than the rest.

Rega Fono MM
As the most expensive preamp in the bunch by far (~$400), one would hope that it would sound better and it does. It has better attack and sustain than the TC-750, and is a bit clearer sounding. It's resolving and has good clarity. I found on the AT440MLA it was a little too bright, but on the Ortofon Black it sounded better. I believe the TC-750 is a bit bright. The bass extension was great and the mids were detailed.

Agreed with everyone above. The Parasound definitely is a smoother and warmer sound than the Mani which has a slightly more solid state sound to it. Great for bassheads that also like added warmth. Hits hard and low. The 750 w/ a good PS is amazing bang/buck and my preferred of all (haven't heard the Rega). Should be a no brainer for the leaderboard. Do note that there are two 750s with very slightly different RIAA measurements that may or may not be audible to some.

With gain pot:



Without gain pot:

He still has my TCC AFAIK

Yeah, I have your TCC with the gain pot.

Wow, I picked up a TC-750LC per the recommendations of this thread and I'm really impressed. I'm using a Marantz tt-15 (w/ stock Clearaudio Virtuoso) -> tc-750lc -> Ragnarok -> Stock HD600/650/800 and I immediately notice a much lower noise floor compared to my Hagtech Bugle 2 (with the stock wallwart) and it seems much more engaging & dynamic overall. I'm using the "upgraded" Magellan 1A SMPS, but I've got the sudden urge to get out my soldering iron & build a Sigma 11 now...

Gratz, glad you like it. We were surprised as well. Maybe hold off on the solder for a bit. We will be doing a Sigma 11 PS shootout versus some cheap shunt regulated power supplies. We may be surprised even further.