I have just bought a M-Audio FastTrack Pro USB sound card, and have just made a calibartion. Use RCA output to unbalanced line input and follow the instructions on the REW calibration guide.
When done, i get this measure:
Hmm I have inserted an image, but it wont show?
See it here: clickit-systems.dk/measure.jpg
Sample rate: 48000Hz
-3dB points: 2.9Hz, 4.499kHz
Input device: Line 1/2 (M-Audio FastTrack Pro
Input: No input selected
Channel: Right
Input volume: no control
Input RMS target: -6.0dB
Actual RMS at 1kHz: -7.1dB
Output device: Line 1/2 (M-Audio FastTrack Pro)
Output: No output selected
Sweep level: -6.0dB
20Hz .. 20kHz flatness: +2.6, -36.0dB
At first glance, I think it looks pretty bad when made with a sound card which costs $250! I though I would use it for full range measurements too, but already at 400hz the graph starts going crazy!
Is this a normal response? I can still use the money back guarantee from the store, so I hope I can get some fast response from you guys
When done, i get this measure:

Hmm I have inserted an image, but it wont show?
See it here: clickit-systems.dk/measure.jpg
Sample rate: 48000Hz
-3dB points: 2.9Hz, 4.499kHz
Input device: Line 1/2 (M-Audio FastTrack Pro
Input: No input selected
Channel: Right
Input volume: no control
Input RMS target: -6.0dB
Actual RMS at 1kHz: -7.1dB
Output device: Line 1/2 (M-Audio FastTrack Pro)
Output: No output selected
Sweep level: -6.0dB
20Hz .. 20kHz flatness: +2.6, -36.0dB
At first glance, I think it looks pretty bad when made with a sound card which costs $250! I though I would use it for full range measurements too, but already at 400hz the graph starts going crazy!
Is this a normal response? I can still use the money back guarantee from the store, so I hope I can get some fast response from you guys