Reviewing Speakers - Measurements and Listening Tests (Video)

[beaRA]

Very informative! (listened at 1.5X and completely able to follow along) Definitely appreciate the in-depth presentation, Amir!

Something that I never seem to see mentioned though are the variations that exist with each listener's own physiology (outer ear) and their own biological frequency 'response'. I find myself constantly thinking things like....someone could have a big dip in biological frequency response from 3-5KHz....and so a speaker with a bad response that is measured as being too HOT from 3-5KHz would sound good to this person. And therefore, a speaker with a 'proper' freq response (more flat or whatever house curve) would then sound too weak in that same 3-5KHz range. This would certainly be a good justification for trusting microphone measurements more than relying on subjective reviewers (what if the reviewer's own ears have a crappy freq response? All their reviews, at best, are going to be completely skewed). At the same time though, it could also mean that a OBJECTIVELY good speaker could potentially sound NOT so good to someone.
Forget where I saw it, but I seem to recall seeing something several years ago where a laser could be fired at a person's ear drum and, just like a speaker plot, that person's ear drum's freq response could be measured...and then used to create a corrective eq. Seems like the ultimate 'tweak'

But then your entire live audio experience would be colored by this biological frequency response. When it comes to sound reproduction from loudspeakers, wouldn't a flat response still sound natural?

 

[spartaman64]

Let's consider the next logical step in your argument. If 2 is good and 5 is better, and everything sounds the same by the 5th, why not always listen to 5 speakers? Or why not abandon all this tedium and have everyone buy Bose cubes?

If you are trying to uncover the last 10% of performance, you need to create the conditions to hear minor differences, which means listening to a single speaker.

only if they are meant to be used in that configuration. if its sold as part of a 5.1 kit like bose then sure it makes sense to evaluate them as such.

but i guess this is the difference between you guys the enthusiasts evaluating stuff and me as a consumer. im just looking for stuff that sounds good and only really concerned with the end results.
i experienced the same thing in the watch community if two watches look as good as each other under my naked eye then ill consider them equal but other people put them under microscopes and say one watch has less flaws than the other in 200x magnification so it is better lol.

 

[amirm]

only if they are meant to be used in that configuration. if its sold as part of a 5.1 kit like bose then sure it makes sense to evaluate them as such.

What if that reduces the accuracy of what the reviewer tells you about them? Still want him to do this?

 

[DualTriode]

Reviewing Speakers - Measurements and Listening Tests

Testing and measurement of speakers is an incremental process that begins with frequency response, may include loudness & distortion tests but always includes critical listening for spatial location with a speaker pair.

Thanks DT

 

[Jim Shaw]

Members here are no stranger to the battle between trusting measurements versus listening tests as performed by reviewers at large.

A major effort. I hope this type of topic continues to flower.

 

[Madlop26]

I have been thinking and thinking about listening testing, the thing is that human senses are far from perfect. We have created simple devices that outperform us in many specific tasks, no human will beat a simple thermometer to measure temperature. Our eyes can see only a fraction of the electromagnetic spectrum, and our ears only hear a fraction of the sound frequencies there are, so how much can we really trust our own listening testing? after all we are using a quite limited tool, which lacks in sensitivity but most importantly consistency. Our sound perception can vary widely according to our health status, mood, preconceptions.......so many bias. yes of course you can fix that with blind testing, but let's face it, it is unpractical, imaging doing a rigorous scientific blind testing in each devices Amir has reviewed.
So in my obsessive quest of the best possible perfect sounding music (even if i can or can't really hear the difference, haha), i find myself trusting more and more in the practical way, measurements... but don't take me for granted , i am not an expert in the area after all, it is just my own opinion which has been evolving in the last years and may continue.

 

[don'ttrustauthority]

Let's consider the next logical step in your argument. If 2 is good and 5 is better, and everything sounds the same by the 5th, why not always listen to 5 speakers? Or why not abandon all this tedium and have everyone buy Bose cubes?

If you are trying to uncover the last 10% of performance, you need to create the conditions to hear minor differences, which means listening to a single speaker.

Because most people listen to two speakers? And two speakers reinforce sound in a room differently than one speaker. There is good reason to measure using two speakers. Just not what Amir is attempting to accomplish. That's the answer you are looking for.

 

[Asinus]

two speakers reinforce sound in a room differently than one speaker

If that were true, most of the DSP applied to audio would be useless. If we hope to use effectively classic filtering techniques we are assuming a linear, time-invariant system (LTI) where the superposition principle holds. There are non-linearities along the chain but most of those are negligible or appear when driving it out of spec.

If the superposition principle applies then testing a single speaker should be good enough, if it doesn't apply you have bigger problems that mono vs stereo.

 

[don'ttrustauthority]

Only if spatial effects are there to cause you take your eye off the ball of tonality.

Exactly why your measurements get a bit of a sneer from me when it results in a thumbs up for KEF? EW. But they're fine when it's my s400 or DCA Aeon RT or Jot 2 or ...

 

[don'ttrustauthority]

If that were true, most of the DSP applied to audio would be useless. If we hope to use effectively classic filtering techniques we are assuming a linear, time-invariant system (LTI) where the superposition principle holds. There are non-linearities along the chain but most of those are negligible or appear when driving it out of spec.

If the superposition principle applies then testing a single speaker should be good enough, if it doesn't apply you have bigger problems that mono vs stereo.

Stereo? Who's talking about stereo. I'm talking about two speakers. This could be why KEF measures good but sound like

 

[oldsysop]

This video shows the lies of 99% of audio reviewers.
Thanks Amir !!!

 

[MZKM]

Stereo? Who's talking about stereo. I'm talking about two speakers. This could be why KEF measures good but sound like

Amir didn’t like the Q models…

If you mean the R3, that may not be your preference due to narrow horizontal dispersion, it’s a tonally good speaker but the envelopment may not be as much as another speaker, but this may be preferred if you are in a narrow room with the speakers near the side-walls.

 

[don'ttrustauthority]

Amir didn’t like the Q models…

Every time Amir pisses me off, he brings me right back in ...

 

[Asinus]

Stereo? Who's talking about stereo. I'm talking about two speakers. This could be why KEF measures good but sound like

OK, I may have phased incorrectly, but the same holds for any number of transducers. If the superposition principle applies, you can evaluate them separately and have an accurate model for all working together. If the superposition principle does not apply there are non-linearities (or time-invariances) that must be dealt with first.

What you are alluding with KEF is more likely to be related with directivity, Dr. Toole mentions in his book about people finding a diffuse field sound more "natural", which is approximated with a lot of speakers around you, but there is also a good approximation having wide directivity speakers with coherent off-axis response interacting with surfaces in the room. From the spin data we know KEFs are on the narrow side of directivity.

 

[Duke]

Only if spatial effects are there to cause you take your eye off the ball of tonality.

Do spatial effects also matter? If not, why not? And if so, then how much do they matter?

Do spinorama measurements and single-speaker controlled auditions - which have combined to revolutionize the industry - tell us everything that matters about spatial as well as tonal quality?

 

[Kal Rubinson]

Do spatial effects also matter? If not, why not? And if so, then how much do they matter?

To me, they are very important for the credibility of stereo image (pair matching is essential) and the soundstage.

 

[Kvalsvoll]

Do spatial effects also matter? If not, why not? And if so, then how much do they matter?

Do spinorama measurements and single-speaker controlled auditions - which have combined to revolutionize the industry - tell us everything that matters about spatial as well as tonal quality?

Spatial is essential, it is this magic appearance of sound objects in our room that makes hifi valuable, if we can not have that, we can just opt for a soundbar and call it a day.

As for evaluation - how good is one specific speaker for reproduction of spatial effects - that becomes difficult to tell in a objective, comparable way.

It is all in the measurements, but it is not so easy to know what to look for. Then we sit down and listen - to 2 stereo speakers, because we believe all spatial information is lost using one mono. If we then write down our impression, this impression is nothing better than a story, because there is no reference, there are no established metrics.

Listening to one speaker can be better when the purpose is to evaluate the sound quality of the speaker as objectively as possible. And some spatial qualities will also be more efficient to judge this way. I often use one-speaker listening during development, because it is more efficient. Some speakers - such as the center - is also meant to be used as one.

Some spatial qualities requires more than one speaker. Such as how good the speaker separates direct instrument sound from the reverb in the recording.

Tonality is just a starting point. But before entering the really fun and exciting aspects of sound, this fundamental property must be reasonably correct.

 

[Spocko]

idk if I 100% agree that you should only test with one speaker and think you should test them in the way they are meant to be used. and if that means a "bad speaker" is going to sound the same as a "good speaker" then doesnt that just mean in actual use they are going to sound the same?

The beneficial qualities of spatial audio generated by stereo imaging also is HIGHLY DEPENDENT on the room: size, acoustic treatment, speaker placement near a wall, seating position near the back wall, etc. Now you end up conflating these environmental qualities with the speaker's innate qualities - this is why some speakers sound like they have muddy bass in one room while in another room the bass is anemic - does the speaker suck or does the room suck? Nearfield mono listening does help eliminate some of these issues.

 

[Spocko]

Spatial is essential, it is this magic appearance of sound objects in our room that makes hifi valuable, if we can not have that, we can just opt for a soundbar and call it a day.

I dare say it is the placement of the speakers within the context of your room and its proper toe-in (or not) that create the spatial cues we love. Ultimately, I believe that matching the right acoustic treatment to the speaker in order to "tune" its soundstage/imaging is required but this completely goes beyond the speaker's qualities. For example, a wide dispersion speaker may benefit from first reflections as it may add further to the soundstage, but maybe it's too much of a good thing and reduces imaging so how much acoustic treatment do you use? Absorption or diffusion or scatter plates? Each one creates a spatial effect that varies from speaker to speaker, and now we end up reviewing the effectiveness of room treatments (4 inch absorption vs 3 inch vs combination diffusion/absorption) and how far away is that side wall and back wall??

 

[Duke]

To me, they are very important for the credibility of stereo image (pair matching is essential) and the soundstage.

Spatial is essential, it is this magic appearance of sound objects in our room that makes hifi valuable, if we can not have that, we can just opt for a soundbar and call it a day.

I agree with both of you. I'm hoping Amir will respond with his perspective, particularly about the sufficiency of single-speaker auditions for evaluating spatial quality.

It is all in the measurements, but it is not so easy to know what to look for.

What are your thoughts on "what to look for", if you don't mind?

Listening to one speaker can be better when the purpose is to evaluate the sound quality of the speaker as objectively as possible...

Tonality is just a starting point. But before entering the really fun and exciting aspects of sound, this fundamental property must be reasonably correct.

Agreed.