Which Digital processor/equalizer ?

The deq2496 placed between the transport and dac does not seem to degrade the sound in any way, introduce glare or grain or anything like that. Even if you don't use all the EQ sections, just reducing the gain and increasing the stereo width makes a sonic improvement in many cases. Just avoid the A/D, D/A conversions.

If you should choose to go with a Behringer unit: Keep in mind that the Behringer ECM8000 mic is not a calibrated mic. It's response below 100Hz is inaccurate(fast roll-off), and that's why the following advice is found on page 15 of the DEQ2496's operations manual: "Press the large data wheel to exclude individual frequncy bands from the AEQ mode. These bands will not be processed by the Automatic Frequency Response Correction. It makes sense to exclude the low frequency range(up to 100Hz) from Auto EQing, because it is this range that may produce inaccuracies during the calculation of the frequency response, which may impair the results achieved with the Auto EQ." The Behringer mic is not provided with an individual calibration disc. Were you to purchase a mic that comes with a calibration disc(ie: a LinearX), there is no provision for entering the mic's curve data into the Behringer's response calculations.

Rodman99999...I guess the ECM8000 mic is not individually calibrated, and absolute SPL measurements might be off. However, the plot of frequency response (typical I suppose) is quite flat down to 50 Hz (where the plot ends) and the frequency response is quoted as 15-20KHx without a +/- dB number. Your suggestion that it falls off fast below 100 Hz does not jibe with my experience, and with results using the RS meter and Rives CD (which many people seem to believe). Where did you get this idea?

Whatever.

Fact is that I and some others find that the autoeq works fine all the way down to 20 Hz. The Behringer manual says it "may" not work well below 100. Perhaps they are worried about room resonances, where placement of the mic might yield various results. Of course each user can try it both ways, and make their own decision.

The Rives CD is excellent, BUT: How flat/accurate do you think the pick-up in a Radio Shlock SPL meter is at low frequencies(You have GOT to be kidding)? What good are response numbers without a +/- db figure(could be +/- 15 to 20db for all you know)? What do you think running a room EQ is supposed to check for? Identifying room resonances, nulls, peaks, etc. all are part of your measurement goals(why you're supposed to aim the mic at the ceiling). Where do I get my info with regards to these mics? By comparing them to actual calibrated and corrected professional mics and RTAs over the years. Whether you believe any of this or not is irrelevant, as long as you're happy with whatever you're trusting in/listening to.

BTW: If you happen to own a Behringer ECM8000 mic: Look at the frequency response curve(typical) that they have printed on the side of the box in which it came. The response actually starts to drop at 200Hz and is 2db down at 100. By 50hz, it's down 5db and rolling off even faster(they cut off the curve at that point).