Why don't all speaker manufacturers design for flat on-axis and smooth off-axis?

[March Audio]

Thanks for answering

Well, you give the obvious answer yourself:

FREQUENCY RESPONSE IS NOT THE SINGLE MOST IMPORTANT FACTOR.

Size is. Headroom is a derivative of size. And size and headroom are cost driving.

For what I know my MacBook Pro speaker is probably flat and smooth. But I would prefer a legacy and not so flat and smooth JBL horn speaker with a 15 inch woofer when listening to music. Do you see my point?

I am not making an absurd example here. We have in recent years experienced speaker producers claim ridiculous bass extension and talk of «small big speakers» that are flat and smooth but will fail miserably against some of the big legacy design speakers.

Again: This is not critique of your research per se. But your and others’ research has been misused (because marketing people and even some people at ASR say it’s only FR that matters) to sell speakers that fail for obvious reasons (they’re too small to deliver what they promised).

Further to illustrate my point: Take a look at Harman Kardon’s top speakers, the Salón and the M2. Both are BIG, and the Salón costs a lot. If FR were the only game in town, why spend so much on a Salón speaker if a Devialet Phantom has similar FR specifications?

Clearly a speaker that is too small to have decent low frequency extension does not meet the criteria that encompasses "frequency response".

 

[amirm]

Why is it that you find the quoted JAES article of no relevance?

Because it is not what you think. Nor is it relevant to the topic at hand.

The study I quoted goes to the precise need we as audiophiles have: which speaker is liked better, by a statistically significant number of listeners and what metrics predict that.

The study you linked to is not that at all. They set out to define a few subjective terms (e.g. BassPunch) and then try to see what measurements can correlate with what the rating of the trained listeners were in that regard. It is like trying to define some flavor in wine and seeing if a chemical make up can be correlated to it. It says nothing about whether said wine will be preferred by majority of people.

Indeed in the key metric of "natural," the study failed to generate useful results:

In addition as you see, they realized that these characteristics that were defined in advance were actually correlated in some cases. The ones they did use are all correlated to frequency response anyway.

The study is also very small scale and authors readily state that it cannot be generalized. Harman study is very extensive across many listening tests, and countless speakers, type of listeners, etc. This is why it has the weight that it has.

Bottom line: this study is orthogonal to what makes a good sounding speaker. They are trying to give you vocabulary to describe the sound of a speaker, and a model based on measurements to predict that. I guess if you wanted to design a speaker that had high "BassPunch," this paper would be a start on how to go about that. Good luck trying to market such a concept though.

Furthermore, such sub-spectrum analysis is also used in Harman listening tests just as well. This is how data on importance of bass performance was generated for example.

As to your personal note, I have listened and participated in Harman testing twice. I have first-hand feel for it. I imagine you have no such sense about this test. Nor have you read it from what I can tell. Just handing things to use to analyze instead of doing your own homework to understand the scope of a test and its relevance.

And oh, Genelec speakers were used as anchor in the study. May that be the reason it is on your radar???

 

[Blumlein 88]

I remember the predictions from spin-o-rama results on bookshelf speakers without response below 100hz was close to 100% correlation. I don't know, maybe @Floyd Toole could answer about why. I'd assumed it was because at lower frequencies in their test rooms the response of the speaker was more corrupted by room modes and uneven response even when the speaker was fine in an anechoic chamber. That would fit with FR being even more of a direct indicator of how well quality of a loudspeaker is judged in listening tests.

I also wonder if there are thoughts on why something like the Quad's mentioned earlier seem to have a very high appeal to those who hear them while not being that good? Or maybe if it is anything more than the novel appearance, operation and expectation of the speaker without a box?

 

[amirm]

For what I know my MacBook Pro speaker is probably flat and smooth. But I would prefer a legacy and not so flat and smooth JBL horn speaker with a 15 inch woofer when listening to music. Do you see my point?

I am not making an absurd example here.

It doesn't get more absurd than that example. No one here needs to be told of the difference between your laptop speakers and the JBL. What they want to know is from hundreds of floor standing and bookshelf speakers, which are likely to sound good. They don't want to know if their laptop speaker sounds as good as one of them or not.

 

[Blumlein 88]

They look so similar, and I had every expectation they would sound pretty much the same. I have difficulty telling them apart visually, but I must admit they don't sound at all similar. I don't get it. Even blind there is no mistaking one for the other. People complain Apple charges too much for their hardware, but in this case I think JBL has them beat.

 

[Juhazi]

That's not a fair test, looks like MB and M2 were positioned differently!

About EQ, I love to use DSP-xo to make the speaker to have good acoustic xo slopes and straight response when measured semi-anechoically. After that just tonality and low bass contouring by listening, by personal taste. I don't use high-Q "correction" for room response at all, but adjust speaker and spot positioning.

 

[daftcombo]

For what I know my MacBook Pro speaker is probably flat and smooth.

Probably not. I would expect poor bass extension, so a drop in the mid-bass area.

 

[Cosmik]

How do people here imagine that speaker design is done? If the designer accepts that a speaker should be flat on-axis (should it, in all types of room, if the dispersion is not uniform at all frequencies?) and 'smooth' off-axis, then how might they go about achieving it?

This could go from dropping some drivers and passive crossovers in a box and hoping for the best through to super-sophisticated simulation and DSP. Measurement, you would think, would be best in the role of confirming a design rather than being fundamental to the method of designing itself.

With that in mind, why would a potential customer deal with those companies that can't possibly be doing more than the dropping drivers and passive crossovers in a box and hoping for the best? And yet they do.

 

[Krunok]

They look so similar, and I had every expectation they would sound pretty much the same. I have difficulty telling them apart visually, but I must admit they don't sound at all similar. I don't get it. Even blind there is no mistaking one for the other. People complain Apple charges too much for their hardware, but in this case I think JBL has them beat.
View attachment 29715

View attachment 29716

Sorry, but your test sucks - that pathetic notebook cannot possibly compete with M2s. My Lenovo, on the other hand, is practically in the same league with them. Check the photo and see for yourself:

 

[March Audio]

How do people here imagine that speaker design is done? If the designer accepts that a speaker should be flat on-axis (should it, in all types of room, if the dispersion is not uniform at all frequencies?) and 'smooth' off-axis, then how might they go about achieving it?

This could go from dropping some drivers and passive crossovers in a box and hoping for the best through to super-sophisticated simulation and DSP. Measurement, you would think, would be best in the role of confirming a design rather than being fundamental to the method of designing itself.

With that in mind, why would a potential customer deal with those companies that can't possibly be doing more than the dropping drivers and passive crossovers in a box and hoping for the best? And yet they do.

Simply because 99.9% of hifi consumers have zero knowledge/understanding of the technical issues. They also buy with their eyes just as much as their ears

 

[Juhazi]

Cosmic - That's not a realistic scenario. If there is an acoustic effort applied, it is for straight on-axis at 1-2 meters anechoic, not at room, and smooth DI. This is the starting point, getting some desired sound at spot in a typical room is called voicing. Room/spot response is sum of power response and interferences in the room.

 

[Krunok]

How do people here imagine that speaker design is done?

Most of the people don't imagine pretty much anything. Just take a look at the number of folks on this forum who can "hear" the differences bweteen DACs, power cables, I won't even bother to mention flatearthers, folks who don't believe we went to the Moon etc..

 

[Krunok]

That's not a fair test, looks like MB and M2 were positioned differently!

About EQ, I love to use DSP-xo to make the speaker to have good acoustic xo slopes and straight response when measured semi-anechoically. After that just tonality and low bass contouring by listening, by personal taste. I don't use high-Q "correction" for room response at all, but adjust speaker and spot positioning.

By listening? Are you saying you're doing EQ not based on measurements but only by listening?

 

[Juhazi]

Krunok - yes! I do take measurement at spot and around it of course, but just for fun and learning. They also help positioning and I can clearly see changes in reflection etc. I use REW and look at impulse, distortion, RT, decay etc. too.

Oh yes, I have eq'd spot to ideal response, but it always makes the sound strange. So not my cup of tea and I can't recommend it to anyone.

 

[Krunok]

Krinok - yes! I do take measurement at spot and around it of course, but just for fun and learning. They also help positioning and I can clearly see changes in reflection etc. I use REW and look at impulse, distortion, RT, decay etc. too.

Oh yes, I have eq'd spot to ideal response, but it always makes the sound strange. So not my cup of tea and I can't recommend it to anyone.

Room EQ cannot be done properly by listening nor by measuring at a single spot. The only way to do it properly is by means of averaging spatial measurements.

Let me quote Dr. Toole on that:

 

[svart-hvitt]

It doesn't get more absurd than that example. No one here needs to be told of the difference between your laptop speakers and the JBL. What they want to know is from hundreds of floor standing and bookshelf speakers, which are likely to sound good. They don't want to know if their laptop speaker sounds as good as one of them or not.

If you read what I wrote, my fish to fry was THE MARKETING of speakers like Devialet Phantom which is specified at 14 Hz - 27 kHz, with an error of plus/minus 2dB.

If frequency response mattered the most, this speaker would outperform both M2 and Salón. Obviously, it doesn’t.

In another thread, you also wrote that a speaker like Kii sounded like a small speaker.

And that is my entire point: Frequency response can be misused for marketing purposes. Users like yourself will not be fooled, but I think many people have been misled.

Focus on headroom too, is therefore in the consumer’s interest, if he wants a sound that he could describe as «authoritative», «punchy» etc.

 

[edechamps]

If FR were the only game in town, why spend so much on a Salón speaker if a Devialet Phantom has similar FR specifications?

If you read what I wrote, my fish to fry was speakers like Devialet Phantom which is specified at 14 Hz - 27 kHz, with an error of plus/minus 2dB.

I'm not sure which exact model of Devialet Phantom you're referring to, but Devialet Gold Phantom measurements are very far from +/- 2 dB. There's a pretty obvious valley around 2.5 kHz which is about 5 dB down. The valley is in the midrange and is quite wide, which makes it worse. Other speakers like JBL LSR30x or Kali LP have a significantly better response for less than a tenth of the price. The only thing that I find interesting about the Devialet is its artificially boosted low frequency extension.

 

[svart-hvitt]

I'm not sure which exact model of Devialet Phantom you're referring to, but Devialet Gold Phantom measurements are very far from +/- 2 dB. There's a pretty obvious valley around 2.5 kHz which is about 5 dB down. The valley is in the midrange and is quite wide, which makes it worse. Other speakers like JBL LSR30x or Kali LP have a significantly better response for less than a tenth of the price. The only thing that I find interesting about the Devialet is its artificially boosted low frequency extension.

See:

 

[Krunok]

The only thing that I find interesting about the Devialet is its artificially boosted low frequency extension.

I agree. Would be interesting to know max SPL to which it can hold that LF extension.

 

[Krunok]

Although he is right, specs are there but measurements obviously differ quite significantly.