The other day, I purchased a brand new set of paradigm mini-monitors and a marantz DV-8300 SACD/DVD player that I bought used. I am very new to the whole high-quality A/V scene, so I've been using a low end Yamaha htr-5640 A/V receiver. What receiver do you all think would well compliment a the paradigm speakers and marantz player? I'm looking for something under 800 if possible with accurate sound reproduction rather than power. I am probably going to use the system to listen to music moreso than movies.
Congrats on your purchases of the SACD/DVD player and speakers. Those are very nice choices.
Ther are a limited number of good options here, given your budget, although there are some very good ones. First, since you appear to want an audio/video receiver, that eliminates a number of options, including stereo receivers and stereo integrated amps. Second, since you want an AVR (audio/video receiver), there are only five brands that I would recommend. Most mass market brands install very puny, near worthless power supplies, which includes your Yamaha. These brands love to boast they have around 100 wpc, but that is a lie. They barely have 100 wpc when driving only two channels into an 8 ohm short. Drive five real speakers at the same time and you are lucky to get 1/2 of the rated power (1/3 rated power being more common). For example, the Yamaha RX-640, which I think is the same receiver you have (Yamaha sells the htr series and the RX series receivers through different retail channels, but they are the same unit with very minor differences--just like mattresses) is rated by Yamaha at 90 wpc, but when driving 5 channels in bench tests, it will clip at 39 wpc. This is directly because of the cheap power supply these mass market brands install.
There are five brands that are widely available that actually produce the power they are rated at across all channels. They are: Harman/Kardon, Marantz, NAD, Outlaw, and Rotel. There are others, such as B&K and Arcam, but these brands are usually hard to find and quite a bit more money than your budget. Of the five I named, I would not recommend the H/K or the Marantz because they are both very warm and a bit dark sounding, which is a bad combo with your Paradigms. If you had Monitor Audio or JMLabs speakers (both rather bright sounding), the H/K and the Marantz would be at the top of my recommendations, but such is not the case. Your Paradigm speakers are very warm and laid back sounding, consequently, you need something more forward and dynamic sounding to get the most out of those lovely speakers.
Of the remaining three, you can eliminated the Rotel as it will cost about twice your budget. That leaves the Outlaw and NAD. The Outlaw receiver, available only from Outlaw directly, is a 65 wpc x 7 receiver that costs $899. Whether you want to stretch the extra $99 is up to you, but it is a very good receiver. I recommend the Outlaw for your speakers.
I would also recommend the NAD very highly. It is a combo that works great with Paradigm speakers and they have two model that would work within your budget. The T743 (50 wpc x 5) can be had around $550 (MSRP $699), and the T753 (70 wpc x 6) can be had for around $795 (MSRP is $999). NAD receivers almost always understate their power as bench tests consistantly find they have an additional 15% more power than their rated power, and they have even more than that with their high dynamic headroom for musical transients. This is not something to overlook. A couple of years ago, I heard the T742 (predecessor to the T743) simply blow away three other receivers, all rated at "100 wpc." Even though the T742 had half the rated power, it definitely had more real power when driving speakers and sounded like the most expensive receiver of the group (it was the least expensive, as a matter of fact). Like the Outlaw, the NADs are wonderful receivers to listen to music with and make for a very fine AVR.