Looking for an upsampler-which one?

I have a large cd collections played on a Classe transport and dac. I would like to try one of the new upsamplers. It seems that there are a number on the market and I have no local dealers. I have no interest at this time in SACD or DVD-A. I'm looking for an improvement in playback of cds not just a different sound. I understand that The Parts Connection has an unit that works quite well but haven't heard it. Any help would be appreciated.
If you can afford it get the dCS Purcell 24/192 upsampling unit. If you are on a budget pick up the Perpetual Technologies P-1A. My buddy has the P-1A and P-3 DAC combo and it is quite refined.

Good luck.
Ditto on the Purcell. It's fabulous, but only if your DAC can do at least 24/96; otherwise it's a waste.
Somewhat depends on your price point, but I guess if you're entertaining the dCS suggested above you've made price a moot point.A single box unit that I currently own is the Audio Aero Capitole, which does 24/192. They also have a DAC unit which does the same. This is an incredible sounding piece of gear. I previously had a dCS Delius/Purcell combo, which was quite good. I prefer the Capitole, I haven't heard digital get any better than with this unit. It also has about 3.5 V of output and a volume control, so you can drive your amp directly, bypassing your pre-amp, if so desired. The results of this must be heard to be believed.
Thanks for the information, actually the dCS is out of my range. I am looking in the under 4000.00 range, new or used. The Audio Aero sounds interesting, I will research it. Thanks again.