How do I set sampling rate to 24/96 for all tests? Help directory implies 24 bit can only be selected for Impulse Response tests.

[JEJ]

How do I set sampling rate to 24/96 for all tests? Help directory implies 24 bit can only be selected for Impulse Response tests.

 

[John Mulcahy]

Word length depends on the driver and the device, not on REW. On Windows the Java WASAPI exclusive drivers or ASIO drivers will provide the maximum resolution the device has to offer.

 

[JEJ]

Word length depends on the driver and the device, not on REW. On Windows the Java WASAPI exclusive drivers or ASIO drivers will provide the maximum resolution the device has to offer.

Under the Preferences window, I can set the sampling frequency, so REW does control the sampling frequency of the ADC for creating the spectrum analysis of the analog signal from the device under test, such as an analog preamplifier. My sound card can do up to 24 bits and a frequency of 192 kHz, so if I set the sampling frequency to 44.1 kHz, will the spectrum analysis of the analog input signal use 24/44.1?

 

[John Mulcahy]

Under the Preferences window, I can set the sampling frequency, so REW does control the sampling frequency of the ADC

Not necessarily. If you are using ASIO or Java WASAPI Exclusive drivers on Windows the device will operate at the rate set in the REW preferences and the options in the Preferences will be the accepted sample rates. Some devices need to be configured through other means or only operate at a single sample rate, in those cases the only rate available to select will be the rate the device is set to.

When using non-WASAPI exclusive drivers on Windows or Java drivers on macOS the rate set in the REW preferences is used to request data from the OS, but the OS will resample the data from whatever rate the device is using if it is different.

In all cases the sample rate and sample format are shown at the bottom left of the REW main window. Note that drivers may (usually will) use a 32-bit sample format for 24-bit devices.