New users guide to REW

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   I am using REW with the Minidsp umik1 which comes with a calibration text file.

I am measuring 2.8V on the speaker outputs of the amp both during level test and the sweep. REW is measuring a peak of 148dB but sounds more like 100dB to me and handheld db meter says 94dB.

why does a calibrated mic not give correct levels? do I have to do something else to calibrate it?

EDIT: I am doing this on my kitchen table at the moment just getting it all working before I take it outdoors (rain permitting). Could this be something to do with windowing the measurement? 

Edited by snowflake - 27 July 2021 at 4:31pm

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snowflake Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3121	Post Options Post Reply Quote snowflake Report Post Thanks(0) Quote Reply Posted: 27 July 2021 at 4:26pm
	I am using REW with the Minidsp umik1 which comes with a calibration text file. I am measuring 2.8V on the speaker outputs of the amp both during level test and the sweep. REW is measuring a peak of 148dB but sounds more like 100dB to me and handheld db meter says 94dB. why does a calibrated mic not give correct levels? do I have to do something else to calibrate it? EDIT: I am doing this on my kitchen table at the moment just getting it all working before I take it outdoors (rain permitting). Could this be something to do with windowing the measurement? Edited by snowflake - 27 July 2021 at 4:31pm

snowflake Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3121	Post Options Post Reply Quote snowflake Report Post Thanks(0) Quote Reply Posted: 27 July 2021 at 10:17pm
	think I've found the problem - my calibration file starts with: "Sens Factor =-.8599dB, SERNO: 7043288" when it should be in the form Sensitivity -12.34 dBFS EDIT: managed to resolve the issue without adding this line to the cal file Edited by snowflake - 28 July 2021 at 2:09pm

snowflake Members Profile Send Private Message Find Members Posts Add to Buddy List Old Croc Joined: 29 December 2004 Location: Bristol Status: Offline Points: 3121	Post Options Post Reply Quote snowflake Report Post Thanks(0) Quote Reply Posted: 28 July 2021 at 10:58am
	minidsp have released new cal files that are 3dB different to old ones - so it is worth downloading new version. don't think this is going to solve my 40dB discrepancy though EDIT: I reinstalled REW with the latest version and it is now giving sensible readings - 106dB @2.83V/1m Edited by snowflake - 28 July 2021 at 2:11pm