Newcomer Questions About Setup And Measurements

[Metronome]

1) Following along with the topmost setup video on the Room EQ Wizard website, I am trying to create a calibration file for my audio interface. It says I need to plug the output of my interface directly into the input of my interface. I have a Focusrite Scarlett 4i4, and when I described what I was trying to do, the Sweetwater customer service folks sold me two JG2TRS-15 line cables. This appears somewhat different than the second cable used in the video, but perhaps that's because it's a different interface? Do I just plug one line cable into any line input and any line output on the Scarlett? Do I need two cables, one for each audio channel perhaps?

2) The video stresses the importance of the reference microphone having a calibration file, but the cheaper of the two models in the video description (PreSonus PRM1) does not actually have one available. The company claims that a calibration file isn't needed. Is this an issue?

3) When I did a trial measurement without calibrating either the audio interface, or the reference microphone, I received two warnings. I did not have the microphone or speakers in a good location, but I was wondering whether these would constitute serious issues with a measurement or not?

 

[John Mulcahy]

Do I just plug one line cable into any line input and any line output on the Scarlett?

Use the input and output you will later use for measuring.

Mic cal files are important if you want to look in detail at response above a few kHz, where mics can vary a lot. Less of an issue for looking at low frequency behaviour or how sound decays in a room.

From the messages it looks like the mic input gain should be increased.

 

[Metronome]

Use the input and output you will later use for measuring.

For right now I just have computer speakers (not going through the audio interface), and the reference microphone does go through the interface but through the XLR port. I was told by the customer support they've never heard of connecting XLR to XLR on the interface, and they suggested the cables that connect line to line on the interface, so now I'm not sure if that's actually what I need.

 

[John Mulcahy]

Either is fine, the XLR connectors are combo anyway and will accept jack plugs.