# Dirac vs Audyssey vs Nothing: What to make of these graphs?



## alphawave (Sep 20, 2014)

Hi, so I'm very new to this. I have my PC going into a Denon X4000 AVR via optical toslink. I have two main speakers (B&W 602s3) and a sub (SVS SB-2000).

I am using a Umik-1 with the calibration file as the mic.

The results are in the overlay graph. Two things immediately spring to mind:

1. Audyssey (XT32) seems to have put a massive trough (null?) at around 90 Hz. :dontknow:
2. Dirac (trial version) seems to have done virtually nothing (when compared to the control). Maybe I have something set wrong as Dirac certainly looked like it was going to do something (see other attachment) :huh:

Apart from that, I'm not sure what to make of the graphs. All comments/ideas gratefully recieved.


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## Wayne A. Pflughaupt (Apr 13, 2006)

It would be helpful to know the scaling of the REW graph (?? dB - ?? dB vertical, ?? Hz - ?? Hz horizontal). The indicators are too tiny to read on my laptop. I think the font size is something that can be adjusted.

Regards,
Wayne


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## primetimeguy (Jun 3, 2006)

My guess is the dip at 90hz is related to a phase issue with your mains and sub. Try tweaking the sub distance a couple feet to get it to go away.


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## alphawave (Sep 20, 2014)

Wayne A. Pflughaupt said:


> It would be helpful to know the scaling of the REW graph (?? dB - ?? dB vertical, ?? Hz - ?? Hz horizontal). The indicators are too tiny to read on my laptop. I think the font size is something that can be adjusted.
> 
> Regards,
> Wayne


Hi Wayne, hopefully this graph should be easier to read.

EDIT: Hmm, still not that easy. It's 45 - 105 / 15 - 200 per the forum spec requirements.


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## Wayne A. Pflughaupt (Apr 13, 2006)

alphawave said:


> EDIT: Hmm, still not that easy. It's 45 - 105 / 15 - 200 per the forum spec requirements.


Got it. :T 

Might be hard to believe, but the differences you’re seeing on the graph in all likelihood are not great enough to make an audible difference, the possible exception being below 20 Hz.

I expect that no two auto-calibration systems process and correct exactly the same way, so it wouldn’t be unusual to see some discrepancies.

Regards,
Wayne


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## alphawave (Sep 20, 2014)

Oh, OK thanks Wayne. So do the graphs look OK generally, please?


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## Wayne A. Pflughaupt (Apr 13, 2006)

Things would sound better if the depressions between 40-50 Hz and 70-95 Hz were eliminated. :T

Regards,
Wayne


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## Flak (Nov 15, 2013)

Hi Alphawave,

it seems to me that the REW measurement of the Dirac correction is not representative, it is possible that the filter was not enabled and that would explain why there seems to be no difference with or without Dirac correction.
A reason could be the following as explained here (section 3.6 Why there is no validation feature?):
http://www.dirac.se/en/online-store/-frequently-asked-questions-and-free-pdf-manual.aspx

"If you want to measure the result of the filter you can either use some application such as HolmImpulse, or you can select the Dirac Audio Processor as the output device on the sound setup page. If this method is selected it is very important to note that the Dirac Live Calibration Tool will disable filtering in the Dirac Audio Processor before each measurement, and you will have to enable it manually real quick. The reason the Dirac Live Calibration Tool disables filtering is that most measurements will not be for validation but for room analysis, and in this case any filtering has to be disabled"

 Flavio

P.S. It is also possible that the filter is not enabled in the DAP; either because some incompatible sample rate is used or because the Filter switch is Off.
I'd suggest a look at the bottom of page 40 in the user manual.


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