Do you correct above Schroeder/transition frequency? If yes, how?

[NTK]

There is a difference between "WE measured 32,000 loudspeakers in homes" and "we have 32,000 USER measurements of loudspeakers in homes". I think the former sounds VERY unlikely, he would have to be extremely well resourced to do that.

And if it's 32,000 USER measurements ... you run into all the usual problems. Uncalibrated / poorly calibrated microphones, poor measurement technique, poor signal-noise, incorrect measurement volume, etc. I have examined dozens of measurements posted on ASR. I usually compare them to the anechoic measurements if they are available. I can tell you there is a lot of variance from home measurements taken by unskilled users.

Anyway I have no doubt that some companies have thousands of user measurements on their database, especially companies like Dirac, Audyssey, and Genelec.

My guess is that those measurements could be from measurements made during THX certifications. Note that the acronyms THX stood for Tom Holman's Experiment.

THX Certified Cinemas – an uncompromised movie experience

Whether you’re a die-hard film fanatic or a once-a-year-moviegoer, a trip to the movies will always be great at THX Certified Cinemas.

www.thx.com

 

[fcracer]

I'm interested in how people decide the upper correction limit for room correction. Above the Schroeder/transition how do you distinguish between room correction, speaker correction, L/R matching, and mic position artifacts.

How high do you allow correction (up to 500 Hz, up to 1khz, or full range)? Above transition do you use broad shelves/tilt only or detailed correction? Do you try to preserve the speaker's response or do you correct it fully for a neutral response? Does your answer change for music production vs listening? What sounds best to you?

I use Dirac Live and allow it to correct from 27Hz to 14KHz. You can see the settings and in-room measurements here. It mostly corrects my speakers in the 3-10KHz range because they’re not ideally linear in that range. I will say however that leaving it uncorrected does make the speaker sound more impressive initially, but gets grating after prolonged listening. I much prefer Dirac correcting the full range.

 

[thcdru2k]

I use Dirac Live and allow it to correct from 27Hz to 14KHz. You can see the settings and in-room measurements here. It mostly corrects my speakers in the 3-10KHz range because they’re not ideally linear in that range. I will say however that leaving it uncorrected does make the speaker sound more impressive initially, but gets grating after prolonged listening. I much prefer Dirac correcting the full range.

This is helpful and kind of where I’m landing. It seems like the answer is less about a fixed upper limit and more about what problem is actually being corrected. Blindly flattening the in-room response above transition seems risky, but small/broad correction for speaker response, L/R matching, or obvious placement/boundary issues can make sense. It also brings up more questions how does Dirac or any auto-correction for that matter differentiate between speaker response, room/placement, and L/R matching issues.

 

[thewas]

My guess is that those measurements could be from measurements made during THX certifications. Note that the acronyms THX stood for Tom Holman's Experiment.

THX Certified Cinemas – an uncompromised movie experience

Whether you’re a die-hard film fanatic or a once-a-year-moviegoer, a trip to the movies will always be great at THX Certified Cinemas.

www.thx.com

From the article text:
"In a career spanning 55 years, Tom built consumer electronics and loudspeakers, was involved in founding multiple companies, taught at University, and wound up at Apple for 10 years. The organizations were Advent, Apt, Lucasfilm, USC, TMH, Audyssey, and Apple, all trend setters"

Or even from Audyssey.

 

[TheKoC]

I use Dirac in a 6.1 system, and have tried several cutoff-frequencies for it's correction, from 500 Hz to 5000 Hz.
Just for Stereo music listening, I found no real difference between them, so whatever it is correcting there has a mild effect in my specific system.
For Surround, the difference is much more audible, and the integration works better with correction higher up. But I currently have side surrounds that are very different from my L/R speakers, so that is to be expected. If they were the same manufacturer / model line, this might be different.