Receiver - Computer - Interface Connection for Measurement and Calibration

[saponico]

Hello REW Support!

I am struggling with the connection configuration with my equipment. I have watched many videos and read many pages on the Internet, but I am still not sure I am connecting everything up correctly when a receiver is in the mix.

I attached 3 pictures:

1. My proposed connection of equipment to perform a measurement
2. One example of a connection configuration that makes logical sense to me for creating the loopback connection to measure all equipment in the system.
3. One example of a connection configuration that I observed online.

Are you able to provide guidance that this is or is not the right connection configuration(s)?

Thank you so much!

 

[Wayne A. Pflughaupt]

First, welcome to the Forum!

Things are a bit confusing, since you have three points, but only two of the pictures are numbered.

2. One example of a connection configuration that makes logical sense to me for creating the loopback connection to measure all equipment in the system.

AFAIK, the interface is only connected to the computer during the loopback calibration. The Scarlet connects to the computer via USB, not audio cables. No mic connected during the calibration.

Keep in mind that calibration is only necessary if you intend to run acoustics measurements like ETC and RT60. For frequency response measurements, it’s not necessary.

For measuring, this is the correct connection scheme:

Regards,
Wayne

 

[saponico]

First, welcome to the Forum!

Thank you Wayne!

Things are a bit confusing, since you have three points, but only two of the pictures are numbered.

I apologize for the confusion. The picture filenames were labeled as Slide 1, Slide 2, and Slide 3 to correspond to my 3 bullets. It would have been better of me if I added that number to the images.

Keep in mind that calibration is only necessary if you intend to run acoustics measurements like ETC and RT60. For frequency response measurements, it’s not necessary.

I would like to be able to measure RT60.

AFAIK, the interface is only connected to the computer during the loopback calibration. The Scarlet connects to the computer via USB, not audio cables. No mic connected during the calibration.

I am new to using non-USB microphones, so please excuse my ignorance. So, the interface (e.g., Scarlet) becomes the sound card instead of the onboard computer's sound card? The Scarlett then just transfers data to the computer via USB?

Would another (better?) option be to use the EMM-6 with just a 48v phantom power supply and connect to my mic input on the computer? Would this simplify everything?

 

[Wayne A. Pflughaupt]

So, the interface (e.g., Scarlet) becomes the sound card instead of the onboard computer's sound card? The Scarlett then just transfers data to the computer via USB?

Correct.

Would another (better?) option be to use the EMM-6 with just a 48v phantom power supply and connect to my mic input on the computer? Would this simplify everything?

You’d be blazing new ground with that one – haven’t heard of anyone doing it.

Ruminating a bit, I don’t think it would work. The sound card sends the audio data from the mic to the computer via the USB connection. So it won’t work connecting the mic directly to the computer’s mic input.

Regards,
Wayne

 

[saponico]

Wayne, thank you very much for all the responses and guidance!

In the picture you posted, why does the interface output only come out of the right channel? Is this intentional so that signal is identical for the processor's left and right channels?

 

[Wayne A. Pflughaupt]

Can’t say, it’s an old picture with an old interface as an example. If your interface only sends (for example) the right input to the right output, then you’ll need a splitter as pictured. If either input sends to both outputs, then you can just connect two cables from the interface to your audio system.

Regards,
Wayne