Any opinions on Acurus amps?

Bright/Shrill is a good description of their amps. They also will distort much more easily than others in their class.
The Act3 is a nice sounding pre but don't lose the remote.....why do you think they are cheap?
For the same money, buy adcom or rotel.
Obviosly I've had bad experiences.

I need to very much pipe in here....
...as an audiophile with "an ear", I would dissagree that the Acurus amps are bright in general! I owned the superb little ACT 3(only a bit higher noise floor than some if not careful with system matching speakers), and sonically (agreeing with above posts), it's better than any B&K pre/pro ever made! It's very clear, detailed, dynamic, and neutral sounding. Again, 90db sig/noise only, but otherwise, excellent! I also had the 100x5, which was probably the prettiest sounding, most detailed(not bright, sorry), clear, extended(again, not bright, or shrill, thx), neutral, and musical little amp I've owned in 5 ch! It's not warm as the the overly borring and soft B&K and Bryston junketh(IMO), and is rather special sounding. The Parasounds are warmer in boddied, if a little rolled on top, which works excellent with some set ups. Still, that 100x5 was sweet!!!!!! With the right speakers, "rolled off at 80hz" or "small", it was a DEFINITE WINNER! I say this, and I've owned, Classe, Threshold, Pass, Aragon(didn't like the 8004 or 8008bb at all!!!!...plain a bit, and rolled on top a tad), Coda and others. Naw, I think that 100x5 was extremely good, and underated. The 200x5 was a tad brighter, I'll conceed that...can't speak for the othe rAcurus amps.
Actually, I only liked the still slightly warmish Aragon Soundstage and Paladiums ok. Everything else, in amps/pre's, etc, was just descent. Classe was better, if less powered, but similar.
Still, for what the Act 3 and 100x5 offered, there's nothing that can touch that sound for that money! For under $1k, you can get a gorgeous sounding separates system, run everything as "small" on the pre/pro, and use the sub! That is audiphile budget surround at it's best...IMO.
As for the Rotel and Adcom, they can't compete at that price for multi channel, sorry! I've sold all the above lines extensively. Parasounds amps used stomp all that, and the lesser powered Acurus as well as described. The Used B&K's are just not that special either(IMO ofcourse)

I’m brand rabid for Acurus gear, having owned an RL11 Line Stage Preamp, A150 Amp and an ACD11 CD player since the late 90’s. My gear has never been in the shoppe and in 23 years, I’ve only had to replace two fuses, left channel, no big.

Before I settled on Acurus, I tried every 90s ENTRY LEVEL system out there, including BRYSTON (Too soft sounding) ADCOM (Too course sounding without SLAM), ROTEL (Loved their RB980BX, absolutely hated the matching RC980 Full function Pre), NAD, PARASOUND, B&K, you name it. Nothing can touch my Acurus on Kick Drum 🥁 impact or Bass S-L-A-M or Sound stage per dollar 💵 spent.

Is Acurus PERFECT? No. They are so BRIGHT sounding you can read a tech manual, 8pt font in pitch darkness with them playing. So slap 👋 a Tube Phono Stage to play records and a DAC to smooth out the Digital. Finally, NEVER run the RL11 with both Tape outputs (Record & Listen) to the same number (eg Tape 1 R&L) because you’ll destroy the Preamp!!!

If cost is no object, a KRELL or LEVENSON will beat my Gear—-but nothing under $2K each will touch it. My Neolithic ACD11 trounced a new Emotiva CD player and is unbeatable with my SMSL 6th Anno DAC with LPS @ 24/192hrz. The maximum PCM you can extract off of a digital output. Google Acurus and read the reviews...

Old thread but I too have nothing bad at all to say about Acurus.  Rock solid reliable, bass slam/punch off the charts, and IMO not bright or shrill but dead pegged on neutral even with my very efficient horn loaded(compression titanium drivers) Klipsch RF-63 floor standers.  I own and have owned 12 of their amps and all have been excellent performers especially for their prices on the used market.

Bill