new review just arrived in this months Hifi news … (JUNE)
"FR30 are nothing short of remarkable setting new standards of focus openness, weight and control at this price and well above"
well done Paul and the PS audio team…
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I wonder about the strong treble peak and the quickly dropping bass in that diagram.
Speaker measurements can be misleading. Once it lands in your room, driven by your electronics, that graph ceases to have any meaning.
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I admit that I have trouble discerning meaning from such graphs. I know “flat” is a theoretical ideal in certain contexts, though.
All that said, given the design of the speaker and the way its drivers are laid out, I wonder about the materiality and relevance of a “traditional” measurement of frequencies at 1 meter. 
Your thoughts…? Others’ thoughts…?
Cheers.
Definitely…just usually such graphs are made in a meaningful environment I thought.
If they measured at 1m I agree.
Great questions. I just think that wherever it’s measured will be a different environment to my house, so I just assume the sound of it will only be known once I get it home. That’s the thing that puzzles me about speaker measurements - they rely so much on the room they’re in that the measurement can cease to mean much to anyone who doesn’t have the same situation. Some manufacturers measure in anechoic chambers, some outdoors in free space, some in domestic settings, and some in their workshops. Not much relevance to me? I get measurements for streamers, DACs, amps, etc, because they don’t rely on the room to do their thing. And then there are magazine reviewers who measure! I can’t imagine their results can’t closely match a manufacturer’s method. Whom do we believe?
Impedance plots are okay to believe, right? Am I missing something? Very happy to learn something about this topic.
Mick
The snippet refers to near-field analysis and “freefield corrected to 1m”.
Not sure what this means (and not trolling); just trying to understand the implications of the measured results.
One of the most frustrating things about Hi-Fi reviews (and reviewers) for me is knowledgeable, technical reviewers often fail to take the time to interpret measured results and postulate conclusions that are relevant to the use of the measured devices for their intended purposes in the field (outside of the lab). It is self-evident (at least to me) that data is usually useless without context, interpretation and interpolation.
Regards.
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Yes. Exactly what you said! Thank you for stating it so eloquently.
Mick
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I think that’s why the 1M measurements are made: to eliminate the speaker/room interaction but the question still remains as to how meaningful they are.
EDIT: One (former) reviewer, John Atkinson, comes to mind in that he always would mention that some measurements were not meaningful when dealing with planar speakers because their surface was a study in chaos theory.
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I would say there’s certain conclusions that can be drawn, if we start seeing patterns from several reviewers, all in different rooms, who measure peaks or dips, and or verify those anomalies in listening sessions.
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I would like to see horizontal off-axis responses too to see if the treble responses smooth out a bit? At least from this measurements, there are lots of peaks and valleys in the upper mid-range and treble regions, not sure the cause, but from watching GR research video could be null points between cross-over points? timing and blending between drivers at microphone position, especially only at 1m.
Comparing to Kef Blade Meta, similar bass response, with much smoother treble:
What was the Percentage Score given?
The subjective overall review score I mean, not asking about measurements.
90% for FR30, 90% for Kef Blade Meta
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That’s a good score
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Well, the review was about as positive as I could have hoped for and working with HFN was great.
As far as the technical questions go, if you read the analysis, along with the measurements, I think that it’s helpful.
Paul Miller at HFN does generally excellent measurements but, as he mentions, these are directly on-axis gated to around 4 ms (with the speaker sitting on the ground) and then with close mic measurements of the woofers and PRs summed into the response.
The bass extension is -6 dB at 24 Hz (which they commented was impressive in the analysis text) and smoothly tapers to this depth. It is challenging to measure PRs in the method that HFN uses because you get “cross talk” with the active woofers. JA at stereophile sometimes uses an accelerometer to directly measure passives to point out this challenge.
As a point of contrast, for on-axis frequency response measurements, John Atkinson at Stereopihle measures similarly but averages things across a 30 degree horizontal window.
In our case, the design was optimized for “flat” for this spatially averaged measurement - something that the spinorama type measurements call “listening window”. We have a bit of a 7 kHz “dip” in our waveguide - this is the width of our ~ 2" tweeter diaphragm and there is somewhat complex edge behavior here. We also have quite wide coverage (about 140 degrees) out to 12 kHz and so this small dip at 10-12 kHz fills in. The tweeter is rather large (as compared to a 1" dome) and somewhat directional overall, so the slightly lifted treble response and 17 kHz peak (where the tweeter is only about 30 degrees of coverage) horizontally and even more narrow vertically) balances out.
He mentions in the analysis about speaker toe in/out and treble balance and in the text of the review they had generally very positive things to say about the tonal balance, I think.
Long term, I would like to work on approaches to make the top octave of planar tweeters more constant directivity (some work from Alcons, Dolby and others has been done here), but I would agree with their listening and measurement impressions that the tweeter sounds balanced, if very slightly “airy” and the low distortion and particularly clean decay and lack of resonances and delayed energy are a feature of these drivers.
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Thanks Chris! I couldn’t read the review yet, just the small screenshot shown here.
I think as scotte1 said, for those like most of us who don’t know how to exactly interpret all the circumstances and scales compared to other measurements of speakers, such graphs are more or less meaningless and misleading. They would have to put them in relation to other measurements made under the same conditions.
On the first view the graph looks peculiar, which it maybe isn’t if one knows everything about its surrounding conditions and how other speakers would look like besides it. Finally it counts how it sounds 
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Yes, I’m happy that we’re in good company with this percentage score. The Wilson SabrinaX and Sasha DAW also got a 90 percent, with the Magico A5 getting an 89, for instance.
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Chris thank you, that’s great. I think I’d need the sane information across 20 speakers, repeatedly hearing the jargon and consequences, before it meant much to me. I can see that the off-axis info would be handy for judging toe-in.
Fantastic news that the review was so positive and I’m sure you and your team are happy with the recognition of your labours. Congratulations!
Mick
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