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Discussion Starter #1
In connection with an earlier thread about smoothing, I was doing some experiments with REW. I took a single unsmoothed measurement and saved it twice under two different names, then using File, Open Measurement, I brought these two identical measurements into an empty project. Then I performed the following steps:

  1. Select All SPL and verify that the two graphs lie atop one another with a perfect match.
  2. Apply variable smoothing to measurement 1.
  3. Note that the graphs now differ slightly below 100 Hz, with the dip at around 55 Hz being filled in a bit in the variable smoothing case.
  4. Apply 1/48 oct smoothing to measurement 2
  5. Note that the graphs are identical below 100 Hz, while the variable smoothing case is smoother than the 1/48 oct case above 100 Hz.
This suggests that variable smoothing may be 1/48 oct below 100 Hz, rather than unsmoothed. The documentation says the following:

REW documentation said:
Variable smoothing applies no smoothing below 100 Hz, 1/3 octave above 10 kHz and varies between 1/48 and 1/3 octave from 100 Hz to 10 kHz, reaching 1/6 octave at 1 kHz.
I've attached the project with the two identical measurements below.


Premium Member
6,711 Posts
The documentation is wrong (I have updated it for the next beta), it became 1/48 below 100 Hz some while ago - June 2015 I think. The previous definition created a smoothing discontinuity at 100 Hz which could be problematic for auto EQ of some responses.
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