@davedword short answer is if you replace your AVR with 2-channel, you can only play back 2 channels (L-R stereo) of a multi-channel recording. Consider though that most multi-channel audio releases also include 2-channel stereo. Frankly, most of the re-channeling of old releases isn't all that great (unless we're talking Pink Floyd), and you'll get more enjoyment out of a great 2-channel system with millions of available recordings than mediocre multi-channel with only a limited amount of available source material.
Upgrade path question with $2k to spend
I'd like to make my next upgrade in my 2 channel signal path. Right now it goes
Ortofon 2M Bronze (cart) -> Pro-Ject Debut Carbon SB (table) -> Pro-Ject Phonobox DS+ (Pre-amp) -> Yamaha Avantage RX-2070 (amp) -> Focal Aria 936 (fronts) + HSU ULS-15 MK2 (sub)
I understand room treatment can give the best bang but lets count that out for now. From a purely component perspective what do you think I should upgrade? Im leaning towards the turntable. It was my first table and altough I upgraded the cart, its only a $500 table. I was thinking of maybe buying the Rega Planar 6 w/ Aria MC cart.
Suggestions welcome thanks!