1 (edited by London_Sapiens 2024-02-27 18:32:06)

Topic: REW audio interface calibration

I have been trying to calibrate the Babyface Pro in REW but failed subsequently. I might be confused with the channels and various parameters with the physical loopback connection between input 1 or 2 at the back and the right output.
If you have experience, can you help clarify the steps to achieve this first step of REW config?
Thanks!

Re: REW audio interface calibration

London_Sapiens wrote:

I have been trying to calibrate the Babyface Pro in REW but failed suika game subsequently. I might be confused with the channels and various parameters with the physical loopback connection between input 1 or 2 at the back and the right output.
If you have experience, can you help clarify the steps to achieve this first step of REW config?
Thanks!

Connect the Babyface Pro to your computer via USB and make sure it is recognized by your operating system and the RME TotalMix software.

Connect a cable from the right output of the Babyface Pro to the input 1 or 2 at the back. This will create a loopback connection that will allow REW to measure the latency and frequency response of the sound card.

Download and install the latest beta version of REW.

Launch REW and go to Preferences > Soundcard. Select ASIO as the driver type and ASIO4ALL v2 as the ASIO device. Click on the ASIO Control Panel button and make sure the Babyface Pro inputs and outputs are enabled and have the same sample rate.

In the REW Preferences > Soundcard, set the output device to the right output channel of the Babyface Pro and the input device to the input channel that you connected the loopback cable to. You can use the Test buttons to verify the signal path.

Click on the Soundcard Calibration button and follow the instructions to measure the loopback timing and level. You will need to adjust the output and input levels of the Babyface Pro using the RME TotalMix software or the hardware knobs to avoid clipping or distortion.

Once the sound card calibration is done, you will need to calibrate your microphone. If you are using a USB microphone, such as the UMIK-1, you will need to download the calibration file from the manufacturer's website and load it in REW. You will also need to enter the sensitivity parameter of the microphone in REW Preferences >Mic/Meter.

If you are using a non-USB microphone, you will need to connect it to the other input channel of the Babyface Pro and use a sound pressure level (SPL) meter to calibrate the microphone level in REW. You can use the built-in SPL meter of REW or a separate device, such as the Radio Shack SPL meter.

Re: REW audio interface calibration

Thanks, this is super detailed!
What about the loopback button on Totalmix? Is it correct to assume it is not related to this?

Re: REW audio interface calibration

London_Sapiens wrote:

Thanks, this is super detailed!
What about the loopback button on Totalmix? Is it correct to assume it is not related to this?

Yes, this button activates the internal loopback function. The signal on the selected hardware output is directly looped to the corresponding input within TotalMix, so to say a 'virtual' connection on digital stage.

UCX - FF 400 - Babyface pro - Digiface USB - ADI-2 (original)
Mac mini M1 - Macbook pro - iPad Air2

Re: REW audio interface calibration

oli77sch wrote:
London_Sapiens wrote:

Thanks, this is super detailed!
What about the loopback button on Totalmix? Is it correct to assume it is not related to this?

Yes, this button activates the internal loopback function. The signal on the selected hardware output is directly looped to the corresponding input within TotalMix, so to say a 'virtual' connection on digital stage.

Would this virtual loopback function be picked up by REW and end up with the exact same result as if the physical cable was used?

Re: REW audio interface calibration

London_Sapiens wrote:

Would this virtual loopback function be picked up by REW and end up with the exact same result as if the physical cable was used?

The physical loopback cable is there to measure the analogue I/O on the sound card, which the internal digital loopback will not include.

If you're using a mic pre with a measurement microphone (i.e. to measure a speaker), I think I'm correct in saying the loopback cable should ideally include the pre (so a jack to male XLR cable is required). 

However you must be careful not to enable phantom power on the loopback input to avoid damaging the sound card outputs.