c weight checked or un checked

[jpv]

I am using the RS digital meter and the cal. file from the download area. My question is in the settings menu under mic/meter c-weight option do I check it or un-check it. I currently have it checked. If I did it wrong how does that effect my prev measurements.
Thanks
John

GREAT PROGRAM by the way

[brucek]

Leave it checked.............

[jcmonier]

No, leave it UNchecked because the RCA output of the RS Digital SPL meter is not C or A weighted, it is "straight" from the electret microphone & internal preamp.

[brucek]

leave it UNchecked

I'm afraid I'll have to expand on my answer Jean-Christophe. We have tested all the RS meter types and have created correction files for them that render the meters flat. REW over-rides the C-Weight box to the upper and lower limits of the correction file and so would have no effect for that region. The calibration correction file compensates for the meters inadequacies in response for subwoofer use. It's not a question of whether the meter outputs true C-Weight or not. The meters are inexpensive and have a poor low frequency response. The cal file we supply corrects for that and results in a flat output.

The cal file use to only extend down to 15Hz and when users measured below that they experienced rising signals that were a point of confusion. We recommended to check the box at that time to alleviate this problem. We have since extended the cal files lower and added a software fix in REW to handle low frequencies that extend below the cal file.

So, you see that it was simply easier to say leave it checked.............


brucek

[jcmonier]

Thanks brucek for those very precise explanation.
It's to leave the C weight box checked therefore...

Many thanks. I understand why now