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Old 22nd October 2009   #2
Pascal Sijen
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The calibration level you are using is derived from a film standard and when compared to movie soundtracks, music tends to be much more compressed, with reduced dynamics and greater overall level. Because there is no recognized standard for monitoring level in the music industry, music mixes may seem too loud when played back on a system calibrated for an 85dBc reference level. Typically for music applications, we recommend calibrating for a lower reference level, such as 78dBc.

With regard to the 500-2500Hz filtered pink noise measuring at around -16dB FS: The bandwidth limited pink noise will read higher than -20dBFS, because pink noise has a high crest factor (12dB), which will throw off the RMS / peak reading on the meters in your DAW. In order to get an accurate reading, you would need to use an averaging technique, where multiple time samples are captured and averaged over a ten second interval to calculate the RMS level. This is why we included the 1kHz test file, which is used for setting the electrical / digital levels. Once you set the faders / output of your DAW to -20dBFS / +4dBu / odBVU using the 1kHz tone, then you should leave them in this position, when doing the acoustic calibrating, using the bandwidth limited test files.

I hope this helps to explain what you are observing.

Cheers!
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Pascal Sijen
Director, Product Management, Cinema Solutions @ Dolby Labs | Former Co-Founder Blue Sky Int. & Audio Design Labs Inc. | I'm also a geek in my spare time.
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