Did I calibrate my soundcard correctly?

[1984911Porsche]

I am using a Soundblaster Live USB, with my Dell laptop, using Windows XP Media center.

I got a message when calibrating "The Highest Level in the Measurement is just 36.8 DBFS"



Thanks for your input?

[brucek]

Yeah, the lower end looks fine, but you're getting some ringing at the upper end. Do you have the soundcard monitoring turned on?

Did you set the levels as instructed, and did that part go smoothly?

brucek

[1984911Porsche]

Brucek,

I can't seem to locate soundcard monitoring part, any idea where to look on the Soundblaster Live USB?

Thanks

[MakeFlat]

Click the EAX icon.

[1984911Porsche]

So does it look correct this time?

[Otto]

Yep, looks good for a soundcard cal. Now, just load that up as the default cal, and then you can remeasure (just exactly the same thing you did). Your result should be a flat line.

Keep going!

[1984911Porsche]

Otto,

I unchecked the C weighted and ran this.

[Otto]

Perfect.

[clubfoot]

If you're using an RS meter don't forget to load the compensation.cal file before taking measurements.

[1984911Porsche]

clubfoot wrote:

If you're using an RS meter don't forget to load the compensation.cal file before taking measurements.

I looked but didn't see this, where can I find it?

Michael

[Otto]

You can download the meter cal files here.

And the setup stuff is in REW here.

Clipboard01.jpg

[clubfoot]

1984911Porsche wrote:

I looked but didn't see this, where can I find it?

Michael

Once you load the RS compensation file "uncheck" C Weighted SPL Meter as shown in Otto's pic.

[adri]

clubfoot wrote:

Once you load the RS compensation file "uncheck" C Weighted SPL Meter as shown in Otto's pic.

Are you sure about this?
The calibration files only have low frequency values upto about 80 hz.
The documentation says, when using a mic calibration file, REW will use the calibration values when provided and use the standard C-Weigting outside the calibration range.
If you turn off C-Weighting, won't you get inaccurate results above 80 Hz, especially above 8Hz?

Adri.

[brucek]

If you turn off C-Weighting, won't you get inaccurate results above 80 Hz, especially above 8Hz?

With the C-Weight unchecked, REW will extend and continue the calibration from the last entry. Since the calibration files are normalized to 0dB, then the line will extend at zero.

From 80Hz to 200Hz, this would be the same as the C-Weight curve, so no difference.

Below the calibration file, the data is invalid with or without the C-Weight compensation. The meters and mics can't measure accurately below that.

brucek

[clubfoot]

adri wrote:

Are you sure about this?
The calibration files only have low frequency values upto about 80 hz.
The documentation says, when using a mic calibration file, REW will use the calibration values when provided and use the standard C-Weigting outside the calibration range.
If you turn off C-Weighting, won't you get inaccurate results above 80 Hz, especially above 8Hz?

Adri.

I agree that the documentation does not specify to turn it off when using the RS meter correction file, but that's what brucek suggested and the RS meter is not very good for calibrating in the upper range.