Re: Overkill for Polk SR6500's??
The SR6500 are very very good set of comps. I considered the polk 6500 on the higher-end. Why do you think you are going to be able to hear a major difference through your speakers by how high up the food chain in the HU department you go.
If you are looking for a great SQ deck then your generally looking for these things no matter who makes it:
24 Bit DAC--Burr Brown being the better IMO
4 volt or higher pre-out voltage
Quality of internals
X-over ability if going active
Here are some HU for to look at that are considered many to be on top of the SQ heap. This is not all just a short list off the top of my head. Just compare them to either Nakamichi you mentioned to help you sort out the Naks. I think most would consider the CD700 equal to or be better than some of the deck listed.
Alpine 7909, 9835, 9855
Eclipse 8053, 8443, 8454, 8455
RockFord (Denford) RFX8250
A bunch of the Denon HU
If you are looking for all SQ then look into a mid to higher end amp, this is personnel preference though. However, there are some very good budget amps out there that will shock you.
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