comments:
Sold my rig but was very happy with this very compact 300Wx2 amp for $70 https://a.co/d/00T1U331
Skip the subwoofer. Add a Speedwoofer or an SVS later when you have the dough. This is a temporary deal while it lasts - buy these now... https://listenup.com/products/triangle-borea-br04-bookshelf-speakers-pair-clearance-open-box And then buy an Aiyima A07... https://www.amazon.com/AIYIMA-A07-TPA3255-Amplifier-Digital/dp/B08CJZGT6H/ And then just a few extra bucks on required cabling. Throw the speakers on top of some old, unused encyclopedias and position them well equidistant from both ears, tweeters at ear height. You ain't doing better than that outside of some used marketplace miracle.
The amplification in the A3+ is barely a sidegrade compared to what's built into the RZ-50 frankly. If you want to go cheap but still offload some work from the AVR, then use some cheap class-D amps for the surround/height channels like the Aiyima A07: https://www.amazon.com/AIYIMA-A07-TPA3255-Amplifier-Digital/dp/B08CJZGT6H If you are externally amping the LCRs, the cheapest I would go while still getting an actual upgrade over the RZ50's built-in amps would be something like this Tonewinner AD-3240PA: https://summithifiusa.com/collections/tonewinner/products/tonewinner-ad-3240pa-3-channel-power-amplifier