Noob! Please help me replace my old power amp, some candidates listed.

Welcome, @caseylol !

I'd stay away from the older amps as they most likely could use a recapping.

I'd give the Class D GaN a shot. I'm sure it's returnable if not to your liking?

The good news is theres a lot out there that will be a big improvement, I like how your thinking, starting with a good amp IS the foundation of a great sounding system. Have you thought about a Integrated amp? This kills a lot of birds with one stone ( no IC cables, Pre amp is built right in as well as a Phono pre ,possibly) SO I would look at a few nice quality Integrated amps.

   Also, you can skip all this equipment and go with a Nice pair of ACTIVE speakers that already come with Amps, DAC’s, Pre amp, all this is built in and you dont need anything but a source component like a turntable or digital music streamer. KEF makes some very reasonably priced Active speakers (LS50W) as well as many other manufactures.

      Minimally if you just want to change your amp, I would look to the used market and find a ADCOM GFA 555/555-II and find a nice tube based pre amp to pair with it, the Adcom was designed by Nelson Pass from Pass labs and is a real sleeper in the audio world, Paired with a proper pre amp it is excellent sounding, and Powerful (200/300 wpc 8/4 ohm), these amps were known to be in many record stores back in the day and they never shut off , they ran 24/7 and worked like battle ships (even better). People that used them at home im sure never came close to that many hours thats why you can still run them without having to replace caps! even after all these years. Sure some of them need to be gone through, ADCOM is still in business. 

https://www.usaudiomart.com/details/650297245-adcom-gfa-555mk-ii/

https://us.kef.com/products/ls50-wireless-2?variant=42122054795511

Matt M

Thanks @thecarpathian! Indeed, sweating over cap jobs and such is the business I want out of. And you're right, I should take advantage of return policy and just see for myself.

@mattmiller, I'm pretty happy with the performance of my pre and speakers. The only knock on the C1 is the phono pre which is why I use the TC... cheap but I've A/B compared it to Cambridge, Shiit and  one other I forget and it stands up fine. IIRC the C1 is Baxandall. ADCOM, NAD and Carver are some I've seriously considered but ultimately decided against because reasons. Also only the original GFA 555 is Pass, not the II or Pro; also the GFA 5300/5400/5500/5800 and GFP-750 pre. And yeah, my Yamaha M50 is still kickin' on original caps, seems okay, but I worry about it. More importantly, while the M50 is respectable I think/hope I can do better. But I certainly take your points, thanks!

Class D has changed a lot over the years and while you'll stil find Luddites who automatically crap on it, there are quite a few companies making good ones.

Not Class D, but I'd look at the Schiit Vidar 2F. Plenty of power. Made in the USA with no distributor and retailr markup so you're getting a $1900 amp for $799. 

Hello Caseylol !  Stsrke Sound makes a very fine 4 channel amp that can be run as a four operated as a operated as a 200+ wpc four channel, a 3 channel ( 2 at 200 + wpc and one 400 wpc, or a two channel, both 400+ wpc unit. It is lway less than $2000 and is warmer and smoother than the Purifi amps. I have ftwo of the stero Purifis and six of the Starke sound amps (one new version, 5 of the original model). They are superb driving Maggies and Martin Logan ESLs. They are also excellent driving the four driver Linkwitz 521s.  I have five systems and a very tolerant wife. Some times they are on sale. Maybe 4th of July? Enjoy the Music