Alan Shaw on Anechoic and Simulated Measurements

[tktran303]

Well nothing stopping Alan and others measuring accurately without an anechoic chamber or NFS.

You know, good old fashioned belt and suspenders engineering.
They did get people to the moon with a calculator…

3 options for manufacturers to get up to date.

Listen Inc
https://www.listeninc.com/20-20khz-free-field-measurements-without-an-anechoic-chamber/

the late (and great) Jeff Bagby

http://audio.claub.net/software/FRD_Blender/White Paper - Accurate In-Room Frequency Response to 10Hz.pdf

and of course, @napilopez
https://www.audiosciencereview.com/...ents-spinoramas-with-rew-and-vituixcad.21860/

 

[thewas]

Also we shouldn't forget that even worst case deviations in the lower bass of a couple of dB play in practice no real role as that region depends much more on the room acoustics, loudspeaker and listeners position placement and even recording and personal preference.
Which actually shows that this is a repeated (AS had written similar stuff in the past in his group) and failed attempt to discredit the importance of measurements and the fortunately rising trend of objective data based reviews like from Amir, Erin and Napilopez.

 

[hardisj]

@napilopez you've got PM.

 

[napilopez]

The Q acoustics 3020i is a good example showing off the FR using the same speaker model, as it's been measured in an anechoic chamber (soundstage network), by the Klippel NFS (Amir), and using quasi-anechoic methods(me):

Here you can see that my homemade method yields better correlation with Amir's than with the NRCs below 200 Hz or so, although it also misses the little blip at 280ish Hz that both the NRC and Amir's measurements show. Note that this isn't to criticize soundstage network or the NRC, i'm simply highlighting a limitation (and there are many limitations to quasi-anechoic methods too).

I do not know if any anechoic only measurements exist for the Neumann KH80 exist, but sound and recording uses a semi-anechoic chamber+ ground plane

That said, and to Shaw's point, it should be noted that my original bass summation for the 3020i was significantly off, by about 4dB at 60Hz:

In this case, it was because the port level was too low in the port+woofer summation rather than where I chose to splice.

But the 3020i is like the second or third speaker I ever measured so I'm going to chalk that up to me not knowing what I was doing that much =] Resumming made the error apparent. Since then I've been able to refine my technique and intuition substantially, but it is true that there is a 'fuzziness' to it. On any given day, I might align the bass sum slightly differently and change the response by a dB or two.

But that also has to be viewed in the context of available measurement systems Considering that it seems pretty much no anechoic chamber available to manufacturers is fully anechoic to 20Hz (though I know some have calibrations to help), you're going to get different results in the bass even if you measure the same speaker in two different anechoic chambers.

So here too the klippel has an advantage, as it appears to perform best from setup to setup in the bass, with most differences visible in the upper frequencies and being attributed to the measurement microphone, positioning, or sample differences. Here's the KH80 as measured by ASR and Klippel itself(at Neumann's request).

Kef R3 hardisj/erin vs amir r3:

 

[TLEDDY]

At the risk of suffering disdain herein:

Electronics - measurement, measurement and measurement; if measurement in the audible spectrum is poor...forgeddaboutit!

Transducers aka speakers - the most important link in the reproduction process! First, measurement - obvious design flaws manifested in Klippel analysis remove from consideration (even if removable by electronic manipulation; room issues excepted).

Finally, and this is always personal, does the reproduction of musical material that I like please me.

My most recent purchase was KEF R3s and a SVS Sub, initiated by reviews in ASR. Damn fine sound!

 

[TLEDDY]

Hmmm...not as disdained as I expected when I made a definitive remark.

 

[DWI]

What is the value of a Harbeth speaker? They don't compete on technical excellence, which is fine. They are sort of nice looking, and sound a certain way which their customers like and expect. It is far easier to differentiate a speaker based on appearance, marketing and 'sound' than it is to differentiate based on technical performance.

Who cares if he's running a cult? Every brand encourages cultishness.

Now, if I was running a content creation company, and someone decided to buy Harbeth's for monitoring, I might be annoyed, but it's not like recording studios earnestly seek accuracy in their monitoring anyway.

The reason is that most consumers buy speakers on how they sound, and they can be dramatically different. It's not by accident either, manufacturer's design different speakers for different market segments. Technical performance doesn't come in to it. Ask my wife, who could easily hear the difference between different speakers with zero technical knowledge.

I had three pairs off Harbeth but never liked the look of them. I put up with looks because they were enjoyable to listen to. When we changed I tried some speakers that are very popular and look great, but I found overly aggressive and fatiguing. I fully appreciate how others may enjoy them, and they are a leading consumer brand that also supply drivers OEM.

Ultimately we chose speakers that we both liked the sound of and she liked the looks. In fact it was the only speaker she liked the look of, thank heavens they also sound very good.