Obviously emotiva and outlaw come to mind two of my favorites. Then for stereo and mono amps you have the Moon neo line, CI audio {mostly mono blocks but talks of a stereo amp system, although when I seen pictures it looks like 2 mono blocks that share a power supply in a separate chassis, still pretty cool though}, peachtree makes the 220 that is a power amp with no volume knob, balanced audio {BAT} makes some impressive tube and ss amps, music fidelity, and yamaha, onkyo and marantz still make the 2 channel models I believe, I know I see the multi channel power amps all the time {overpriced if you ask me}, icon, jolida, and AE {audio electronics, Hercules} make power amps too but all tube....
also NAD, niles, parasound, Russound, and mcintosh
then a lot of pro audio stuff like crown, behringer, QSC, alesis, samason, pile, art, marathon, tech pro, ect, ect, ect....
I am sure there are a lot more and some of them companies like Ci have mono blocks vs stereo amps, I have listened to MANY amps and I can not for the life of me hear a difference in sound quality between 1 vs another, I will admit I can hear how t class and tube amps may reproduce it a little different, but between solid state amps, I say buy the most inexpensive that fits your needs and has the stability and customer support you can live with... I had BK amps for a while but service issues and companies closing and opening and closing screwed me a few times, I find emotiva and outlaw are about as good as any other on the market sound wise and customer service wise easy to deal with, and THEY ARE BUILT LIKE TANKS, my xp5 NEVER SHUTS OFF and works great not a hiccup, my xpa2 has been asked to power some of the toughest speakers made at stomach turning levels for hours and never got 10* past ambiant, my xpa200 powers 12 in ceiling speakers and never gave me a problem... I also like the outlaw 2200's, I prefer mono blocks with stereo systems and they do everything I ask and don't cost much for what you get, plus they are tiny and you barely notice them...
Now as far as "affordable" goes, I have no idea what is affordable to you, there are some good buys and if you are building a 2 ch music system we will need a little more info, like budget, speakers to be driven, room size, listening position from speakers, is there going to be a subwoofer in the system, ect... If you are talking watts per dollar, class d pro amps are going to get you the most power for your money, for example an xls1000 is under $300 and puts out over 200w per channel at 8 ohms...
If its music only i personally like the outlaw 2200's and the xpa2 for a good amount of headroom and pretty much the ability to run any speaker around... the prices are competitive, but if you don't care about headroom and only need say 60w per ch, the m1 is on sale for $500 or so at music direct and is a decent buy if you want something "different"... give us some more info and we will let you know our opinions on what to look into...
