Need to steer away from Bryston amp added to AVR


I have a hamburger budget, but want kobe beef. Need a new menu....

I am researching amps to find the best solution (sound/budget/aesthetics) to add a amp to my very decent denon receiver to improve the sonics for stereo (2.1) music only. I am not expecting the "ultimate"sound just want to have a noticeable improvement in sound. My budget is $700-$850 - Yes, used is fine!! No tubes please.

My current set up, in a 14 x 19 x 8ft living room:
.primary source: G5 Powermac music server - AIFFs via TOSlink
.denon dvd-1730 for CDs occasionally
.denon avr-4306 receiver @ 130W (I will use pre-outs for 2-channnel)
.tetra 120u monitor speakers (8 ohms, 89dB, 50-20k Hz, bass-reflex)
.martin logan abyss subwoofer
.anti-cable speaker cables

Music varies: bjork, stevie wonder, depeche mode, ladytron, the faint, the smiths, ry cooder, gotan project, cowboy junkies, interpol....
medium listening level.

On my current list are a bunch of amps that are 2 - 4 times my budget:

.Bryston model :: 3B SST, 150W, SS ~$3000 MSRP
.Audio Research :: model: 150.2, 150W , Class-T, ~$3000 MSRP
.Bel Canto :: model: S300 (current model), 150W, Class-T ~$1650 MSRP /
model: EVo 200.2 (previous model) 120W, Class ? ~$2200? MSRP


Q: Would something like this parasound amp be a marked improvement over the Denon's internal amp?

.Parasound :: Model 2125, 125W, Class AB ~$700 MSRP

The BIG Q: Which amps should I be looking at instead of these $$$$ listed.

Thanks for any leads you can provide, ed
audioalways
swampwalker,
Thank you for the amp suggestion. Yes, I do realize that my dual purpose system will never reach audio nirvana....you can't convert an suv into a roadster. the denon does have a unique mode that shuts down all the non-audio circuits, etc. during audio playback. I use this mode 99% of the time.
If you are looking at the Parasound 2125, take a look at the Parasound Halo A23. A great sounding amp, that is kind of middle of the road. Can be had for around $525.
want to have a noticeable improvement in sound.

Given the relatively modest size of your main speakers I think you have a great and well balanced set up with your Denon @130 W per channel. I don't believe you can achieve a noticeable difference given your medium listening level requirements. I assume your sub is taking most of the tough LF load away from your main speakers anyway. (100 watts is plenty for all but the very lowest frequencies, as it is the woofer that takes all the juice; your sub has a built in amp so no worries!!!)

Have you considered acoustic treatments? Do you have a PEQ to control the LF room modes (less than 8 HZ)? These options might give you a noticeable improvement.
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I second the McCormack DNA 0.5. You might even be able to get DNA 0.5 Deluxe in that price range. Good luck.