My Graph..Help with room speaker problems

[SDA10]

Hi
Here is my graph for my sub (velo dps-12) and speaker (paradigm studio 20); both were taken as full range measurements (no xover) from my listening position...

Do these look like room problems or speaker problems? Help

Also does this software measure the THD at each freq? I didn't see that... Thanks!
SD

[brucek]

First start with your sub only and the crossover set.

Post the graph with a vertical axis from 45dB-105dB and a horizontal axis of 20hz-200Hz and show your target.

Did you calibrate your soundcard and use the proper soundmeter calibration file?

No, REW doesn't calculate THD.

brucek

[SDA10]

show which target? I didnt calibrate the sound card yet since I plan on using a different one for future tests but the dips are so extreme i think its beyond simply the sound card (how much beyond would be good to test)

I did full range to figure out where to place the crossover...I can do it again..re THD what are the 2nd and 3rd harmonic in the left most pane of REW for then?
Thanks!
SD

[brucek]

show which target?

It would be a good idea to read the REW HELP FILES. They are well written and have lots of this information.

The graph below shows a 75dB target with a SUB tab selected and the range I mentioned to use.


target.jpg

I did full range to figure out where to place the crossover...

Use 80Hz when in doubt.

re THD what are the 2nd and 3rd harmonic in the left most pane of REW for then?

Those are the distortion display. "When the meter is tracking the generator frequency the relative amplitudes of the 2nd and 3rd harmonics of the test frequency are displayed as percentages of the level of the fundamental. For low frequency measurements the subwoofer is usually the main contributor to distortion. If there is clipping somewhere in the signal path this will typically show up as high 3rd harmonic distortion levels. High noise levels in the system will also raise the displayed distortion figures".

brucek