Q re: HifiNews' Chora 826 report

[tifune]

On ASR, Soundstage Network, Audioholics, etc. the common cutoff for speaker FR testing is ~20KHz. If tests were extended out to 40KHz, would it be common to see huge spikes and/or dips like this? Definitely threw me off at first. It's hard to imagine many people enjoying a 10dB+ boost at 23KHz but maybe it's more common than I think since most tests don't display that far? I understand hearing degrades over time at such high registers, but 10dB strikes me as enough to be impactful. Am I mistaken on that?

https://www.hifinews.com/content/focal-chora-826-loudspeaker-lab-report

 

[pozz]

If tests were extended out to 40KHz, would it be common to see huge spikes and/or dips like this?

Yes. Certain tweeters are no longer linear past 20kHz and show random output there. It's a mechanical issue, not a voicing decision.

 

[tifune]

Yes. Certain tweeters are no longer linear past 20kHz and show random output there. It's a mechanical issue, not a voicing decision.

Thanks - are those frequences generally omitted due to irrelevance? Wondering why they were included here but nowhere else, I suppose

 

[Frank Dernie]

On ASR, Soundstage Network, Audioholics, etc. the common cutoff for speaker FR testing is ~20KHz. If tests were extended out to 40KHz, would it be common to see huge spikes and/or dips like this? Definitely threw me off at first. It's hard to imagine many people enjoying a 10dB+ boost at 23KHz but maybe it's more common than I think since most tests don't display that far? I understand hearing degrades over time at such high registers, but 10dB strikes me as enough to be impactful. Am I mistaken on that?

https://www.hifinews.com/content/focal-chora-826-loudspeaker-lab-report

View attachment 96635

I am not sure why they have started adding an octave above what anybody can hear to their measurements.
Certainly any metalic tweeter which is pistonic in the audible range will have an resonant peak like this above audibility. Soft dome tweeters have damped resonance in the audible range and don't act as a piston all the time and won't reach this high.
I don't know if this may create other problems in the audible range if reproducing, say a 96/24 or 192/24 file with energy in this area.
Another reason to stick to CD

 

[Tonygeno]

All of Hi Fi News' measurements seem pretty jagged, particularly in comparison to Stereophile and even Amir's measurements. I'm not sure why.

 

[Frank Dernie]

All of Hi Fi News' measurements seem pretty jagged, particularly in comparison to Stereophile and even Amir's measurements. I'm not sure why.

Probably less smoothing.
It is 40 years since I was doing plots but I remember the smoothing chosen makes a BIG difference.

 

[napilopez]

On ASR, Soundstage Network, Audioholics, etc. the common cutoff for speaker FR testing is ~20KHz. If tests were extended out to 40KHz, would it be common to see huge spikes and/or dips like this? Definitely threw me off at first. It's hard to imagine many people enjoying a 10dB+ boost at 23KHz but maybe it's more common than I think since most tests don't display that far? I understand hearing degrades over time at such high registers, but 10dB strikes me as enough to be impactful. Am I mistaken on that?

https://www.hifinews.com/content/focal-chora-826-loudspeaker-lab-report

View attachment 96635

It could be 20 dB and most probably still wouldn't hear it. Some people might though.

All of Hi Fi News' measurements seem pretty jagged, particularly in comparison to Stereophile and even Amir's measurements. I'm not sure why.

Scaling is a big part of it. They use an unusually tall aspect ratio. If we match it to Amir's and cut it off at 20ish khz, it looks like this:

In the lower frequencies, the low resolution of quasi anechoic measurements will often lead to large bumps and dips that are likely narrower (but perhaps taller/deeper) in reality.