Now what?

[Mike Schramm]

Hello all. Just picked up my UMIK 1 and downloaded REW yesterday. I have seen Matt's video on how to take measurements, and I am easily able to do that. Now my question is: what do I do with them? I'm not sure what they are showing me and I don't know what to do in order to fix whatever is wrong. If you could direct me to an article or video to help I would greatly appreciate it!
Thanks!

 

[Tony V.]

If you like post your results (REW graphs) here and we can walk you though some different options in fixing any issues.

 

[Mike Schramm]

Thanks Tony V.! I just realized that I took my initial measurements with my Onkyo's AccuEQ still active. I need to turn those off before completing REW measurements, correct?

 

[Tony V.]

I would post both before and after graphs as it would be good to see what AccuEQ is doing.

 

[Mike Schramm]

Will do. Can't right now though (I'm at work, haha). Thanks again for the help!

 

[Mike Schramm]

I haven't seen vertical dotted lines like these in any of the videos I have watched. Any idea of what they may be?

 

[John Mulcahy]

That is the phase trace (right hand graph axis) and they are phase wraps. Phase is cyclic, wrapping from -180 degrees to 180 degrees (they are the same point).

 

[Mike Schramm]

Please allow me to apologize up front, I’m completely new to this (and probably annoying as well), but is the phase trace something I need to fix or is it fine the way it is?

 

[John Mulcahy]

You can ignore it, concentrate on the SPL trace - that's not showing up on your image as the left hand (SPL) axis is so low, you can use the scrollbar to shift it or use the Limits button at the top right of the graph to set a specific range. Best posting the mdat file if you would like comments on the response.

 

[Mike Schramm]

I have tried multiple times to upload the mdat file, but after the progress bar gets to 100% it fails to upload. What am I doing wrong?

 

[Silverprout]

Please allow me to apologize up front, I’m completely new to this (and probably annoying as well), but is the phase trace something I need to fix or is it fine the way it is?

You can't fix this now, but you should perhaps understand that theses artefacts are generating very deep notches in the frequency reponse and you don't see them in the graph that you've shown because the trace don't have enough resolution.

 

[John Mulcahy]

You can't fix this now, but you should perhaps understand that theses artefacts are generating very deep notches in the frequency reponse and you don't see them in the graph that you've shown because the trace don't have enough resolution.

What artefacts?

I have tried multiple times to upload the mdat file, but after the progress bar gets to 100% it fails to upload. What am I doing wrong?

How big is the file?

 

[Silverprout]

What artefacts?

I try to be as easy to understand as possible, IMHO the absence of corelation of the phase and the frequency response traces at this level of learning will be a problem in the next step of comprehension.

 

[John Mulcahy]

I try to be as easy to understand as possible, IMHO the absence of corelation of the phase and the frequency response traces at this level of learning will be a problem in the next step of comprehension.

There are no artefacts in that phase response and the plot does not show an SPL response, only the calibration file response.

 

[Mike Schramm]

I took a second round of measurements at just the left, right, and left & right locations. My first file must have been too large to upload. Interestingly enough, the phase trace is not in these measurements...

 

[John Mulcahy]

Yes it is, you choose the traces to display by selecting the corresponding box in the graph legend. If you are't seeing phase either the box isn't selected or the right hand (phase) axis on the SPL & Phase graph has been shifted so the -180 .. 180 range isn't visible.

There are large reflections from both speakers in the first couple of milliseconds and the RT60 rises substantially from around 250 ms at around 500 Hz to about 500 ms by 5 kHz, as if the room has some midband absorption but is quite reflective at high frequencies. Suspect that would sound a little fatiguing.

 

[Mike Schramm]

I have no frame of reference to know if it’s fatiguing or not. It very well could be and I just don’t realize it. Can I do anything to counteract the reflections?