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Hi, everyone.

I am a newbie on "room measurement", probably a diehard 2-channel addicts (well, space says so) for both audio & video pleasures. So, here comes asking for coach...

I got a plan for this "room measurement" hobby as several days of reading/surfing around:

1. Radio Shack 33-4050 - I assume I'll have more pal around using this than the digital 33-2055 and might prefer analog over digital for a feeling of its range when using MATT or other testing tones.
1.1 BTW, is anyone can tell me where I can find 1/6, 1/12 octave testing tone, be it sine wave, warble or limited bandwidth pink noise - warble or pink noise are preferred to reduce room resonance influences. Also the location for the excel file download in case I need to do it manually.
1.2 I am a bit confused on how to point the mic toward - upward vs. vs. 45% into the center. There are factors to be considered: mic pattern, pressure/free/diffuse field design etc. From what I've read, the ECM8000 is an omni up to 10K+ under a diffuse field, hence good for room measure and better tuned when pointed upward 70%~80%, but not sure of RS)
1.3 Another reason to go analog is I can always hook up with a DMM, say my Fluke, for a digital readout as long as there is a consistency between needle and line-out. Question: is there a consistency, that is, a linear relationship between needle readout & line-out voltage per your calibration measurement?

2. Behringer ECM8000 + M-Audio MobilePre via XLR cable (say, PROCO SIM-10 10')
1.1 This combo seems most popular at Home Theater Shack, so I assume I can cry out for help here if something went wrong (hope not!). The concern is more on the pre-amp quality when using with a condenser mic, esp. at high gain. Several posts have raise noise issue at high gain (beyond 80% knob).
1.2 I guess I have no way to have the ECM8000 calibrated from where I live, so I'll probably just give it a blind date by using the ECM8000 calibration table as posted here. One thing I do not quite understand well: assuming ECM8000 is quite linear 15Hz~20kHz in a diffuse field, do I still need the calibration table when pointing upward; or is it because the calibration table is intended for use when ECM8000 is pointed toward forward center? I got different answers from ETF and Rives...
1.3 Checking the spec on MobilePre (~$110), it is +/1 0.8dB at 20Hz-20KHz, worse than M-Audio Fast Track Pro (~$150) +/1 0.1dB. I was dancing between these two, but would probably go for MobilePre for its driver stability (lesser functions means easier driver). If I go for MobilePre, I'll need to do a calibration probably using line-out to line-in loop for level matching. Is there any precaution or advices as to your field experiences?

3. Forget me not, the excellent REW. I assume REW will go well with BOTH RS 33-4050 (using its RCA line-out feeding into MobilePre RCA line-in) and Behringer ECM8000 (feeding into mic/phantom of MobilePre via XLR cable).

What do I miss? I have Stereophile Test CD2 and ASC Test CD with me which I use in the past using the most sophisticated yet not reliable device: my ear:duh:

I have a $300~$500 budget for this whole setup. And if there is any side-benefit, I'd love to record some home track, probably using GarageBand comes with my iMac.

For reference purpose, I use both Window & Mac in a 802.11n wireless setup.
Equipment wise,
Linderman D680 SACD ->ARC LS26 -> ARC REF110 -> DALI MS5
SONY SE-1 BD -> Proceed AVP -> LS26 -> REF110 -> MS5 with a SONY 47" BRAVIA LCD

That's all I got for this newbie introduction.

Thanks:hide:
 

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Welcome to Home Theater Shack!

Howdy audiobee and welcome to the Shack!

We are glad to have ya on board... :T


Sonnie



 
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