Audyssey Manual Calibration “OCA’s REW + Audyssey Awesomeness”

[Rednaxela]

The other day I mentioned elsewhere this wonderful video by @OCA. It covers many topics but it has one little trick that is so genius that I think it deserves its own thread.

In short it is to make Audyssey believe that there is nothing to correct about your speakers and your room. This turns your Custom Target Curve into a regular EQ function, and is the key to taking full control of your measurements, measurement analysis, filter design and filter application, as demonstrated in the video.

This is how you do it. (Timestamp intentionally included.)

Sorry perhaps for the shouting, but to me this is the revelation of the year.

 

[OCA]

I have made minor changes in the "dialnorm" settings of the Atmos sweeps of the surround channels since this video. There were 1-2dB deviations from optimal here and there in the high frequencies in the surrounds (AWS mediacreator dialnorm settings are notoriously difficult to master!). You can download the new sweeps (256k, acoustic timing and clock references included) along with the master REW file here:

Optimal Atmos Sweeps 256k.zip

drive.google.com

PS: Use REW's own sweep for the LFE channel instead of the "played" sweep as Dolby Atmos LFE channel comes embedded with a low pass filter which slightly shifts its timing. All other channels are identical to REW sweeps.

 

[OCA]

As you know, it's not possible in the MultEQ Editor app to add custom target curve points to the flat curve and reference curve will always apply a "High frequency roll-off" to itself. Here's a REW filter to remove that completely from the app generated impulse response (I call it - anti HFR1) so you can see the true frequency response of your speakers.

In the meantime, I requested from Sound United to add a HFR0 (no high freqeuncy roll-off) option to the app:

Fingers crossed!

 

[Rednaxela]

Could you not already set that value to 0 in the .ady JSON or am I mixing things up?


Edit: if so, never mind.

 

[OCA]

Could you not already set that value to 0 in the .ady JSON or am I mixing things up?


Edit: if so, never mind.

This was my first solution idea. Unfortunately, the AVR will completely mute after the transfer of any ady file with "enTargetCurveType: 0"


PS And other values like 3,4,5,6.... all default to 1!

 

[Rednaxela]

Right I see.

Time for me to get myself one of these units too to get to the bottom of all this.

 

[OCA]

Mac users who cannot play Atmos sweeps, Auro-3D users who technically cannot have sweeps for certain Auro channels, finally a method to optimize your Audyssey calibration. Only MultEQ Editor app is required.

 

[just1n]

@OCA How do you playback sweep for more than 5 channels on Mac? I can only get the five base channels tested, no heights.

 

[OCA]

@OCA How do you playback sweep for more than 5 channels on Mac? I can only get the five base channels tested, no heights.

Macbooks don't support bitstream output of DD+ over HDMI, they can only decode to LPCM.

You should be able to output 7.1 though. Did you try REW's Java Wasabi Exclusive drivers?

The method in the video above is your best bet to obtain measurements of your Atmos channels with a Mac.

 

[just1n]

Macbooks don't support bitstream output of DD+ over HDMI, they can only decode to LPCM.

You should be able to output 7.1 though. Did you try REW's Java Wasabi Exclusive drivers?

The method in the video above is your best bet to obtain measuremenets of your Atmos channels with a Mac.

I even tried an old dell laptop with HDMI and trying run sweeps on the heights only came out on the front left channel.

I’m going to watch that new video you uploaded and see how you did this. Thank you

 

[OCA]

Windows PCs run the height channel sweeps without problems. You should check Windows Sound/AVR settings.

 

[just1n]

Why don’t you suggest using DynamicEQ with this method?

 

[OCA]

Why don’t you suggest using DynamicEQ with this method?

In this method, filters are created based on Audyssey's own measurements which are taken at 75dB with Dynamic EQ off. Dynamic EQ applies major boosts to bass and treble at 75dB (it only stops boosting at around 100dB which is way too high for anyone to crank up to) and speaker responses will be very different to the Harmon target curve you designed the filters for at 75dB.

With this method, you can compensate for low volume listening with Dynamic volume if you wish.

 

[just1n]

I’m going to try combining this Filter EQ method with the Audyssey DEQ correction method from an earlier video of yours.

We rarely listen with LAeq above 55, 60max. So I really liked the results from that video bringing down the surround channel levels.

 

[DeLub]

This last video led to the best result so far. Thank you very much!

I did a few things differently the second time. I'm using the Bruel&Kjær target curve (you can find it here; you can load it as a target curve in REW's EQ window). This curve has a bit less bass boost, which I think is too much in the Harman curve. I've DynamicEQ turned on, with an offset of 15dB. I chose this offset as the B&K curve is for 85dB, and I normalised all my input sources to -25dB instead of -30dB.

The video does not mention how to volume level the speakers, instead the levelling is "built" into the filters. What I did instead is after averaging all speaker responses I created another average of all the speakers excluding the sub. I opened the EQ window with my target curve and calculated the response level. This number I chose as a target level for all the channels as explained in the video. But before EQing, I shifted all channels as close to this level as possible, rounding to a multiple of 0.5dB. These values I noted in my ady-file. The sub was leveld to this target level as well.

After all filters were created, for each filter I selected the region between 500Hz-2kHz to read the effect of the filter. For all filters this should be negative as in this region no boosts are applied. These number I used to fill the trimAdjustment in the ady-file. I did the same for the subwoofer, but for the 30Hz-80Hz region. This number could be positive, but in my case was negative as well.

Finally, just before exporting the filters to text files, I loaded the inverse of the curve Audissey normally uses as a target (here it is; load it by choosing import frequency response). Then I multiplied all channels one by one with this curve. And these resulting curves I exported.

Still not perfect, but the best result with Audissey I had so far.

 

[OCA]

For those of you who do not have "directional bass" option in their receivers (myself included), it can be done by adding the highlighted changes below in the MultEQ ady file. Both subs can be applied different corrections and their distances and volumes can be adjusted independent of each other unlike in the standard (default) mode where subs will both be named SWMIX and will share a common EQ, relative trim and relative distance.

The drawback is it divides the subs as" left/right" or "front/back" and only uses the sub nearest the speaker for crossovers. Only LFE channel will be sent to both subs together and I guess this will limit its surround use. It could be interesting with stereo set ups.

 

[Pabi]

Hi @OCA,

I recently commented in one of your videos. I wanted to thank you and share with all of you an Excel Spreadsheet, which makes it easier to know what delays in milliseconds need for the filtering from 200 Hz up to 500 Hz, taking the different speed of sound settings (300 vs 343): measurement-infos.xlsx

In order to get it working you need to do the following:

1. Upon opening the file click on Enable Content. The spreadsheet uses Power Query to process the data from the ADY file and this is required:
   

   
2. In the first sheet named "Path" replace the File Path with the path of your own "PerfectSpeakers.ady" file:
   
   
   
   
3. Open the Data Tab of Excel and click on Refresh All. If you entered the right path, it should work correctly and load the data. Ignore or accept any warnings:
   
   
4. If everything went well you should be able to see your Audyssey Data within the Audyssey Info and the Channel Info sheets:
   
   
   

I tried to make it as easy as it gets and I hope it works well for you too!

 

[Pabi]

Hi @OCA,

I am following your last tutorial, but I am unable to measure the relative distance between speakers using the Impulse Overlay. By using the right Shift key and dragging through the plot I just get this message:

Am I using the wrong shortcut? I was unable to find any others using Google.

 

[OCA]

Hi @OCA,

I am following your last tutorial, but I am unable to measure the relative distance between speakers using the Impulse Overlay. By using the right Shift key and dragging through the plot I just get this message:
View attachment 300161

Am I using the wrong shortcut? I was unable to find any others using Google.

You're probably doing a keyboard Shift + Left mouse click. This is for average SPL measurement and is valid only for frequency domain graphs. The metrics you wannna see in time domain will be brought up by keyboard CTRL + right mouse click!

 

[jhaider]

For those of you who do not have "directional bass" option in their receivers (myself included), it can be done...

Why would anyone possibly want do to that, though?

Just because a feature is there, does not mean it's worth a damn. Here it seems like this "directional bass" business will only cause issues.

IMO start with first priniciples - is x useful?