asynchronous USB dac or jitter reducing device


Hello
I have a Red Wine Clari-T driving a huge single driver baffle. The range is roughly 80hz to 15k. I am interested in a macbook based digital system using Wifi or usb. The only piece of the puzzle I have is the MacBook. My budget is less than 1K including airport express or other similar, an asynchronous USB dac and or a DAC and pace-car type reclocker for jitter. If I have an asynchronous USB dac do I need a separate device for jitter? The Pace-car is clearly out of my budget, so what are my options?
Thank you in advance.
nparbat
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2nd Benchmark DAC. I use it with MAC-Mini/Airport Express. Stretch your budget by $150 and get AE ($150) and new Benchmark DAC1 ($995) to obtain 5 years warranty and avoid problems that early Benchmarks had (thin sounding op-amps, high output impedance on unbalanced outputs).
Try an EMU 0404 - with balanced outputs - $185 does the job, sounds great. Yes, audiophiles will not like the plastic case but it works.