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Old 03-02-08, 07:05 AM   #3 (Link)
 
brucek
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Re: Ugghh...help


Let me make a few points about REW first.

It would be wise to use a vertical scale of 45dB-105dB for your graphs. This allows an reasonable swing of +/-30dB (total 60dB) around a 75dB target. Your graph uses a total of ~190dB. This makes the presentation quite kind to your results.
Use a vertical axis of 45dB-105dB.

The horizontal scale shows an extension at the low end to 2Hz. You can see the response of your speakers extending into the noise at about 20Hz. Use this as you bottom figure of your horizontal axis. You've measured to 200Hz, so make that your top figure.
Use horizontal axis of 20Hz-200Hz.

When using waterfal it's most reveiling to use the same axis as the response graphs and also to use a LOG view rather than the LINear view. This way you can use the slider to dial down to a single slice that matches the response graph and then slowly move to 30 and watch the signal degrade out.

Quote:
Is it the room or my speakers or mic???
Not enough information. You need to tell us what type of mic you're using and whether you are using the correct calibration file.
Is this a single monitor at the listening position at the console?
If you know your mic is correct, then you can do a near-field measure of a monitor outside or at least in the middle of a room where there are no boundaries. This will (attempt) to reveal the response of the speaker itself without the room influence.
Then when you know it's not your speakers, take measures at different spots in the room. You may have to move the console a bit to reduce the dip..

brucek


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