First Experience with Audyssey Calibration (not quite what I expected)

[Quiet_Hollow]

to elaborate on this...

 

High pass them there for the express fact that 80 Hz is approximately the -3 dB point, minimizes boundary interaction, saves amplifier power....etc.   ie. It's not just some arbitrary number. Setting the filter there will push down response near 80 Hz another 3 dB (-6 dB total), so the acoustic crossover point to the main channels actually ends up being more near 95 Hz than 80.

 

In addition,

 

Tweaking the main channel(s) highpass will require re-adjusting the subwoofer low pass and volume in combination to match to the new crossover point.

 

 

Single La Scala left main channel in-room response, corner-loaded, no filtering, 10 foot ceiling measured by Audyssey XT32.

0 dB = 75 dB SPL at the listening position.

Edited July 24, 2015 by Quiet_Hollow

[Thaddeus Smith]

So as you can see, moving the mic 1' further away from the MLP didn't really change the results from Audyssey but this will ensure that I'm doing it properly.

 

Headed there now Steven....stay tuned...

 

looks like i was wrong and scrappy was right. thank you for indulging me.

[garyrc]

I agree that the correction table is not necessary for this application.  Is the pink noise you are using "Band Limited Pink Noise," which is often 500 Hz to 2K hz?  That would be outside the range where correction is needed.  The correction tables for some meters (inc Radio Shack) are controversial, anyway.

 

Since, with La Scalas or Khorns, we both have very efficient speakers, we run into the -12 dB problem.  I prefer using 12 dB attenuators on every channel while calibrating, and letting Audyssey set the levels.  This (at our house) produces more like -2 than -12.  I believe Audyssey uses the whole frequency range, with some weighting, to set the levels, rather than a limited band.  After Audyssey is done, the attenuators can be removed, since all speakers are now set for equal SPL from the MLP.

 

The bass on your La Scalas will almost certainly be cleaner than on your (our) RSW 15.  How far down your La Scalas go depends on the room loading, etc., etc.  What did Audyssey come up with for their 3 dB down point?  Wasn't it 50 Hz?  So start by crossing them over at 60 Hz, then play around.

Edited July 22, 2015 by garyrc

[Youthman]

looks like i was wrong and scrappy was right. thank you for indulging me.

This is a learning experience for me.....appreciate everyone's help to make my system the best that it can be.

 

Is the pink noise you are using "Band Limited Pink Noise," which is often 500 Hz to 2K hz?

I'm not sure how to check.  It's the test tones that Onkyo produces in the Levels menu.

 

I prefer using 12 dB attenuators on every channel while calibrating

I could have used them when I had the Sherbourn 200 x 7 amp but I sold it since I no longer need the extra power.  Attenuators won't work with just a receiver.

 

What did Audyssey come up with for their 3 dB down point?

Sorry, I'm not following your question. 

[Youthman]

Audyssey suggested 50Hz for the mains and center.

 

[Quiet_Hollow]

Audyssey suggested 50Hz for the mains and center.

That's okay and is perfectly normal.

 

 

As frequency decreases below 100 Hz, the wavelengths get longer and the low frequency output from the individual channels sum acoustically at the listening position. So even though each speaker cabinet may be rolling off, their in-room combined low frequency performance (the entire system as the mic sees it) remains useable (possibly flat or even increasing). Picking a lower filter point redistributes the power across the system.

 

This also affords a method for standing wave correction, whereby the DSP can sculpt the output of the individual channels in the time-domain to actively counteract resonances across the listening position. Similar to noise cancelling, but using a combination of every availble channel that is capable of supplying low freq content in combination with EQ.

 

So there's two way to go about it.

 

In your situation, I'd stick with what Audyssey suggests, because an 80 Hz crossover point in combination with the La Scala requires a very stout subwoofer.....something with nearly equivalent or better performance than the La Scala from 40-200 Hz.

 

La Scalas can benefit from a sub, but it's hard finding one that actually matches them toe-to-toe.....much less three.    Home theater mixes require a sub, so the game becomes a matter of choosing filter points based on linking everything togehter sonically and maximizing performance without blowing something up.

 

I've tried both ways and found the lower crossover point easier to set up and sounds good at the expense of possibly pissing off the neighbors because of the power it dumps into every channel. Whereas the higher crossover point requires a fair bit of tweaking and a very capable subwoofer, but sounds amazing when dialed-in with the added benefit of keeping the neighbors happy by putting almost all the low frequency energy into the device most capable to handle it.

Edited July 23, 2015 by Quiet_Hollow

[derrickdj1]

Micheal, Gary is saying the room/boundry interaction with the mains selected a 60 Hz XO from autocalibration.  Looking at your data, 60 Hz is a nice starting place for everything(Universal or global XO for all speakers).  An easy way to do it is to pick the XO point of the weakest speaker which is 60 Hz. 

 

The 3 db spec of the speaker is not that important because that was in an open field or anechoic chamber.   Once speakers are in the room there is usually some gain picked up.  Also this is a multichannel set which adds even more gain.  You will not damage anything and a 60 Hz xo, you won't miss anything.

Edited July 23, 2015 by derrickdj1