Measuring mic preamps (and other things)

[pipelineaudio]

Hello all, I see a lot of familiar faces here! I am in the process of making an apples to apples chart comparing mic pres: frequency response, noise, distortion....Could do IMD I suppose.

I REALLY love REW's callibration feature, as I do have some devices I am using for reference that I would like to flatten out to make comparisons more logical.

I am also testing with another software called Rightmark, as it allows me to show multiple devices in the same graph (which REW seems to in some cases) and also allows me to use two different audio interfaces for input and output...this may or may not be all that important to me later on, leaning towards not

I think my big issue with just using REW is that I cannot seem to get the main measurment window to show 0dBFS as the top, though I can get the RTA window to. But the measurment window allows multiple device graphs to show, while the RTA does not seem to.

Also, I am mostly testing distortion with a 1khz sin wave, which works fine in the RTA window, but again, how could I show multiple devices on the same graph doing this?

 

[John Mulcahy]

The overlays window shows all measurements. If you want 0 dB to represent 0 dBFS calibrate the SPL meter accordingly, e.g. apply a -6 dBFS signal and enter -6 as the level in the calibration dialog.

 

[pipelineaudio]

Thank you! I will try that when I get to work today.

How could I make this type of distortion and noise graphs in REW and show multiple devices?:

 

[John Mulcahy]

Save the RTA plots as measurements using the buttons above the RTA graph.