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Discussion Starter · #1 ·
Hello,
I just got the PSA XS15se and trying to calibrate it.

I setup REW with the UMIK-1.

Using the SPL in the software I am hitting 75dB. I am just trying to find the best placement for my sub.

Here is my measurement from one corner, 1/6 smoothing.
 

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You need to post the graph correctly first;

Limits set to:
Vertical = 45db-105db
Horizontal = 10hz-300hz

NO smoothing on sub graphs.

Logarithmic scale, not linear. Use the Freq Axis button i the upper right corner.

Measure from 10hz-300hz.



After you do this, re-post your graph.

Also, I noticed you took a standard screenshot to post the graph...it's much easier if you just use the little camera icon to the upper left of the graph. ;)

You've read the entire guide linked in my sig, right?
 
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Discussion Starter · #4 ·
You need to post the graph correctly first;

Limits set to:
Vertical = 45db-105db
Horizontal = 10hz-300hz

NO smoothing on sub graphs.

Logarithmic scale, not linear. Use the Freq Axis button i the upper right corner.

Measure from 10hz-300hz.



After you do this, re-post your graph.

Also, I noticed you took a standard screenshot to post the graph...it's much easier if you just use the little camera icon to the upper left of the graph. ;)

You've read the entire guide linked in my sig, right?
Thanks.. I will do that.

I have not read the ENTIRE guide! I will print and read though.
 

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Discussion Starter · #5 ·
I went through the REW setup yesterday, so it seems I can start on pg59. Setting up REW for measurements.

I will take measurements tonight with adjustments you mentioned and follow the rest of the guide.

I see others having issues with USB mics if they choose more than 1 sweep. I will post back later tonight.
 

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You mean running more than one sweep?

I've ran dozens of sweeps in succession and the only issue I've ever had is the well-known "screech" bug. If you hear your speakers making horrible screeching noises during a sweep, just change output channels and then change back and it be fine. :)
 

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I've never done that. What is the theory behind setting the sweep count higher than 1?
 

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Discussion Starter · #10 · (Edited)
I'm reading through the doc now.

I'm using my HDMI Graphics Card to output the audio to my AVR.

I downloaded and loaded the calibration file for the UMIK-1 following the instructions.

In the document it talks about calibrating the mic and the noise floor. Is this step necessary for the UMIK-1?

If my noise floor is around 55db, do I need to run the tests at 95db (40db above the noise floor, pg 67)? I apologize if I missed it in the doc.
 

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No SPL cal needed with the UMIK-1 as long as you have the cal file with the sensitivity factor in the first line.

You only need to measure 40db above the noise floor to get meaningful waterfall graphs, for FR an average of 75-85db is probably good enough. However, if you can measure at 95db all the time without disturbing others, it is preferred.
 

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Discussion Starter · #12 ·
No SPL cal needed with the UMIK-1 as long as you have the cal file with the sensitivity factor in the first line.

You only need to measure 40db above the noise floor to get meaningful waterfall graphs, for FR an average of 75-85db is probably good enough. However, if you can measure at 95db all the time without disturbing others, it is preferred.
Alan, again. Thank you!
 

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Discussion Starter · #14 · (Edited)
I took some more measurements yesterday. I tried 3 different locations.
I updated the room image to show where I tried the sub. The graph names are pretty straight forward, FR and FL are shown in the room image.

Which looks best? I left the MCACC configuration on. Should I turn it off when measuring?

I also have the .mdat file:
drive.google.com/file/d/0Bzcnf7E9XntgTjg...VDQ/view?usp=sharing
 

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The FR location for the sub looks the best to me.

You should measure at first with the Auto EQ off, trying to get the best FR you can with sub placement giving your Auto EQ the easiest job you can. The less the Auto EQ has to do, the better. ;)

That being said, that FR position is looking pretty good with MCACC, did you re-run MCACC for each sub position? If not, you should.
 

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Discussion Starter · #16 ·
Alan,
I will do all the tests in pure direct mode, which doesn't use any room correction, as far as I know.

I'll move the subs to the locations I tried previously and remeasure.

I will also add another two locations.

As to your response about FR looking good w/ MCACC, the MCACC was run in the corner, this FR is roughly 4' away from the corner.
 

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^^^

Not sure about your AVR, but on most AVRs Pure Direct mode bypasses bass management. Can't you just turn off MCACC?

I could be wrong, but I don't think MCACC equalizes the subwoofer...if that is correct, you may not have to re-run it every time you move the sub. I would though, just because I'm anal like that. :)
 

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Discussion Starter · #18 ·
I'm not sure... When I put it into 2 channel or Pure Direct, the light for Advanced MCACC turns off.

When I run the advanced MCACC it does set distance and volume for the sub. It selects small speakers with 80hz crossover.

There is a MCACC button on the remote, maybe that just disables it. I'll check that out later.
 

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Discussion Starter · #19 ·

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Nope. The "FR" position still looks better to me. Smoother from 15-50hz and no giant dip at 60hz. ;) Caveat: the "FR" graph has 10db steps and your new graph has 5db steps...kind of hard to make a direct comparison. Try to keep the graphs consistently at 5db steps.

When posting waterfall graphs, set the lower limit to your noise floor (typically 50-55hz) and set the time to 450ms (not 2000ms :) ). Only include the FR you measured - in this case, 15-300hz.

Use 1/6th smoothing on your full range graphs.


That deep (but narrow) dip at ~50hz is present on your FR, FL and CC graphs as well as the sub graph (in front left corner, but not others). It's hard to say if that is being caused by the new sub position or not. I would put the sub back into the "FR" position and remeasure.

That dip is probably not much to worry about though since it is only about 3hz wide. ;)
 
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