Audyssey sub distance exactly double -phase?

[Steam]

Have just Audyssey calibrated my new X8500 and the sub distance is wrong.  
 

What I am wondering is that the sub distance was EXACTLY double the real value.  Was thinking this could be because the sub is out of phase? Does Audyssey measure phase of the  sub?  Been trying to google but getting lots of endless links..   Yes I could go and remeasure everything with the sub phase reversed but hope someone could shortcut an answer.

[Dirkgerman]

From the hip

 

Yea, the doubling of the distance the DSP in the X8500 from the sub is a bit weird and phasing won't  double anything at all really, BUT the sub could be far enough away from the mains to have effect of a very large phase difference between the mains and the sub assumed by measurement and algorithm in programming to be double the distance away.  The main speakers are out of phase with the sub ?(I know this sounds counter intuitive, but personally have a set up like this, mains out of phase with the sub).  This is utilised with an impulse corrected arrangement with miniDSP to excellent effect. 

 

It would be worth trying a couple of things.

Changing the phase of the sub, at the speaker terminal or if available at the sub via switching. 

Moving the sub closer to the center of the room or mains.

Another anomaly encountered with erroneous equipment measurements is the very small room, if possible lower the measurement dB as much as you can and try temporary room treatment, be imaginative

 

How is the system sounding ?  .

 

   

 

Edited September 27, 2020 by Dirkgerman
small grammar error

[JohnL]

2 hours ago, Steam said:

Have just Audyssey calibrated my new X8500 and the sub distance is wrong.  
 

What I am wondering is that the sub distance was EXACTLY double the real value.  Was thinking this could be because the sub is out of phase? Does Audyssey measure phase of the  sub?  Been trying to google but getting lots of endless links..   Yes I could go and remeasure everything with the sub phase reversed but hope someone could shortcut an answer.

Nothing to do with Phase.

Sub distance (delay) will usually measure longer. 

This is a common knowledge Audyssey thing...........nothing to worry about.

 

Ignore distance reading for Sub as Audyssey is actually measuring the correct amount of delay to apply for accurate time alignment.

 

See here......

https://audyssey.zendesk.com/hc/en-us/articles/212340243-Long-subwoofer-distance

https://audyssey.zendesk.com/hc/en-us/articles/212347803-Subwoofer-Distance

http://www.willowville.net/ht/Audyssey Setup Guide.pdf

 

Regarding Phase......select 0 or 180..........whichever outputs highest SPL test tone.

 

Edited September 27, 2020 by JohnL

[Guest niterida]

Yep ^^^^

I set my sub (which is under my couch) by watching a metronome video and adjusting distance until the sound matched the image - it ended up being 7m further than actual and 4m further than my mains.

In other words it delayed every other speaker to give the subs extra processing time in order to catch up.

[Steam]

Thanks for your input.

 

my sub is a Whise 319a and the centre speaker sits on top of it.  Given it’s age it has no dsp so no electronic delay. Room is ~8m x ~4m.

 

x8500 is fantastic.  Upgraded from my old 4308 and was surprised how much improvement it made

 

9 hours ago, JohnL said:

Nothing to do with Phase.

Sub distance (delay) will usually measure longer. 

This is a common knowledge Audyssey thing...........nothing to worry about.

 

Ignore distance reading for Sub as Audyssey is actually measuring the correct amount of delay to apply for accurate time alignment.

 

See here......

https://audyssey.zendesk.com/hc/en-us/articles/212340243-Long-subwoofer-distance

https://audyssey.zendesk.com/hc/en-us/articles/212347803-Subwoofer-Distance

http://www.willowville.net/ht/Audyssey Setup Guide.pdf

 

Regarding Phase......select 0 or 180..........whichever outputs highest SPL test tone.

 

thanks.  This is exactly what I was looking for.  Stereonet is awesome!

 

9 hours ago, niterida said:

Yep ^^^^

I set my sub (which is under my couch) by watching a metronome video and adjusting distance until the sound matched the image - it ended up being 7m further than actual and 4m further than my mains.

In other words it delayed every other speaker to give the subs extra processing time in order to catch up.

hmm..  maybe should give something like this a try

 

cheers all

[davewantsmoore]

13 hours ago, Steam said:

I could go and remeasure everything with the sub phase reversed

I would try this.

 

... but also I would not worry too much about the distance calculated (leave it at what audyssey says) .... assuming it is relatively short (eg. 2m actual, vs 4m audyssey)

[davewantsmoore]

1 hour ago, Steam said:

hmm..  maybe should give something like this a try

I would not recommend that technique.

[Steam]

52 minutes ago, davewantsmoore said:

I would try this.

 

... but also I would not worry too much about the distance calculated (leave it at what audyssey says) .... assuming it is relatively short (eg. 2m actual, vs 4m audyssey)

Yeah.  But I packed the box n mic away and just being lazy.   Audyssey said 6.2m instead of 3.1m.  I manually corrected it but will set it back and see what results.

[Guest niterida]

3 hours ago, davewantsmoore said:

I would not recommend that technique.

Yeah I wasn't suggesting it either - I was just using it as an example to show that AVR distance doesn't equal actual distance.

My sub is used to shake the couch so it was timed by feel, not by sound.

Sorry for any confusion.