Loopback measurement IR difference between 5.20b5 and 5.19

Discussion in 'Official REW (Room EQ Wizard) Support Forum' started by 3ll3d00d, Feb 3, 2019.

  1. 3ll3d00d

    3ll3d00d Member
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    I was checking something and noticed that 5.20 shows a quite different IR to 5.19 when presented with a digital loopback. Is this expected? If so, why?

    Measurement is via a motu 1248 looping back through the driver alone, no DAC/ADC round trip involved, running on windows 8.1. Same REW settings (I think) in either case.

    5.19

    pulse_519.png

    5.20b5

    pulse_520b5.png
     
    #1 3ll3d00d, Feb 3, 2019
    Last edited: Feb 3, 2019
  2. John Mulcahy

    John Mulcahy REW Author

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    That's a result of this change from 5.20 beta 2:

    In essence, the IR now shows the correct inter-sample response, obtained by windowed SINC interpolation. That can be disabled using the IR oversampler setting in the Analysis preferences.
     
    3ll3d00d, akl and andyc56 like this.

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