In room measurements of Beolab 50?

[Bjorn]

Does anyone have in room measurements of the B&O Beloab 50? Conducted in the listening position and either without or with the room correction.

I measured the speaker for a customer yesterday and would be interested in seeing measurements in other rooms for comparisons.

 

[Moti]

Would be interesting to see your measurements as a starter.

 

[Sir Sanders Zingmore]

Beooab 50 Or BeoLab 50?
There’s an “L” of a difference…

 

[Bjorn]

Beooab 50 Or BeoLab 50?
There’s an “L” of a difference…

Corrected. Isn't auto correction on the phone great.

 

[Bjorn]

Would be interesting to see your measurements as a starter.

I don't share measurements at customers home. I would have to ask for permission.

But I can share a nearfield measurement of the speaker. Nearfield here was between 55-60 cm distance and a little lower than 1 m height. Measurement shown with 1/12 oct. smoothing. Room correction was disabled and so was the EQ settings. Speaker set in narrow mode, which is a cardioid directivity.

The speaker suffers from floor bounce like almost all speakers in listening position. Vera Audio Coherence 12 is one of the few that avoids this. With the floor bounce, the speakers ends up having almost a raising response from 120 Hz to the treble. Additionally, it's a speaker that suffers from a good amount of treble diffraction. The speaker uses a dispersion lense.

It seems like the speaker has been tuned very flat from 100 Hz are to 4000 Hz and with raise above 4000 Hz. And boost below 100 high seems high. The room correction actually raised the deep bass more, lowered the floor bounce further (!), added boost in the presence area (!), and didn't do anything to correct the overall tonality to something more neutral (like Bruel&Kjaer response).

I have said it before on this forum: I haven't seen any clear indications that a cardioid dispersion improves the frequency response. The in-room response of a speaker like Vera Audio Coherence 12 is a lot better.

 

[DanielT]

You know how it is; even if your Vera Audio Coherence 12 is a better speaker than Beolab 50, even though Vera Audio Coherence 12 only costs a tenth of Beolab 50, they sell on the brand. Plus it is a lifestyle speaker in appearance:

This is just my opinion and taste but to be honest I think the Beolab 50 looks like a cheap larger Bluetooth speaker. Okay a little better finish than cheap
Bluetooth speakers but beyond that I think that is the case.
Edit:
LG Xboom 360 (XO2TBK) Bluetooth speaker, $199.99 (not super cheap but still). Smaller but check out the similarities in appearance:

(Maybe an unfair comparison, but I just mean the appearance itself)

You have to fight with the marketing and brand marketing of your Vera Audio Coherence 12.They are really good speakers, from what I can tell, so I keep my fingers crossed that their sales will go well.

 

[ssashton]

I've been interested in cardioid speaker systems for many years and have looked into various implementations. In my simulations, many designs only produce a noticeable rear null at a distance of several meters. This could explain why many don't show improved response in typical rooms.

I'd be very interested to know whether you observe a significant reduction in rear output when you simply rotate the speaker and measure at around 1 m distance.

Sorry I can’t contribute any data for your original question.

 

[Bjorn]

I've been interested in cardioid speaker systems for many years and have looked into various implementations. In my simulations, many designs only produce a noticeable rear null at a distance of several meters. This could explain why many don't show improved response in typical rooms.

I'd be very interested to know whether you observe a significant reduction in rear output when you simply rotate the speaker and measure at around 1 m distance.

Sorry I can’t contribute any data for your original question.

The benefit of a cardioid directivity is an overall dispersion that is fairly even. I'm saying fairly, because most seem to vary quite a bit between 120° and 160°. A well designed horn can be a lot more constant FIY. The other potential benefit is a bit narrower horizontal dispersion with less gain on the horizontal reflections compared to speakers with 180° directivity. But again, a horn speaker would minimize it a lot more and even a constant 120° directivity wouldn't bring down side wall reflections much. They will still be very audible from both sides.

I didn't measure the speaker on the rear output. What we do know is that using cardioid below 100 Hz reduces the level and thus increases distortion. And which is the reason most don't run cardioid in the deep bass. Besides, the room will dominate here anyway. So there is IMO nothing that can really be called directivity control for low frequencies in small acoustic spaces. I don't know how low B&O is running cardioid.

 

[sigbergaudio]

I have said it before on this forum: I haven't seen any clear indications that a cardioid dispersion improves the frequency response. The in-room response of a speaker like Vera Audio Coherence 12 is a lot better.

A claim like this needs to be backed up by data.

 

[Bjorn]

A claim like this needs to be backed up by data.

There have been a researcher or two that have shown that cardioid doesn't improve the area of room modes compared to a monopole. They might however give a different result with different positions. Other than that we basically have to look at in-room comparisons measurements. That also why I said: "I haven't seen any clear indications that a cardioid dispersion improves the frequency response".

We do have a member here that have compared speakers with same position in a room and showed the response. Below is the Kii Three (blue graph) with cardioid vs Devialet Phantom (red graph) with a corner placement for both.

The Kii Three with a cardioid directivity offers no benefit here vs the Devialet Phantom. The latter has a much wider directivity and gradually narrows in the highs. Not very constant.

As for the Vera Audio Coherence 12, it does clearly measure better than the Beolab 50. I have shown enough measurements from multiple positions and different rooms to back that up. I'm also confident that it will generally measure more even in-room than other cardioid speakers because of the design. An evidence would require multiple measurements in many different positions and in different rooms.

Since you have cardioid speakers you could contribute here with an AB review between the speakers for a third party to measure like mentioned above. But I have feeling you will decline.

 

[sigbergaudio]

There have been a researcher or two that have shown that cardioid doesn't improve the area of room modes compared to a monopole.

References please.

As for the Vera Audio Coherence 12, it does clearly measure better than the Beolab 50. I have shown enough measurements from multiple positions and different rooms to back that up.

But you haven't shown any in-room measurements of the Beolab 50 in the same positions and rooms for comparison?

I'm also confident that it will generally measure more even in-room than other cardioid speakers because of the design. An evidence would require multiple measurements in many different positions and in different rooms.

Yes it would, and before that evidence is presented you can't state that "The in-room response of a speaker like Vera Audio Coherence 12 is a lot better [than any cardioid dispersion speaker]".

Since you have cardioid speakers you could contribute here with an AB review between the speakers for a third party to measure like mentioned above. But I have feeling you will decline.

This is not how this forum works. You made a claim. Burden of proof is on you to back that up with reasonable documentation and data.

 

[Purité Audio]

When I have had the opportunity to measure a customer’s traditional speakers compared ( placed in the very same position)to the cardioid model (8C Kii3) the i measurements have been tidier through the cardioid region.
The one more or less ‘like for like’ comparison i was able to make was when we had D&Ds 8c and 8M here,( the 8M non cardioid but same drivers/enclosure) the 8C sounded just that bit clearer.
Keith

 

[sigbergaudio]

@Bjorn And my point here isn't really that I want you to provide all this evidence, or even whether I disagree or not. But rather to suggest that you simply refrain from making claims like this.

You are obviously convinced your approach is a very good one. That is no surprise, why else would you create a speaker like that if you didn't think it was a good design? But you can talk about the benefits of your approach without talking about alternative designs in a negative way.

 

[ssashton]

If only these images were still online

Measured monopole and dipole room responses

My initial thought when starting this thread was to explore bass reproduction with monopoles and dipoles in a small room with rigid walls and without any absorption other than normal living room furnitures. This is living reality for many. Let's keep it that way. Discussion requiring heavy...

www.diyaudio.com

 

[sigbergaudio]

If only these images were still online

Measured monopole and dipole room responses

My initial thought when starting this thread was to explore bass reproduction with monopoles and dipoles in a small room with rigid walls and without any absorption other than normal living room furnitures. This is living reality for many. Let's keep it that way. Discussion requiring heavy...

www.diyaudio.com

That discussion seems to focus on various subwoofer approaches(?), that's not necessarily applicable to monopole/dipole/cardioid at higher frequencies.

 

[ssashton]

Thats true, the in room behaviour is different above or below the schroder frequency as Gedds explains in that thread.

Most of the graphs do go up to a decent range though, 500hz or more, so we can gain some insight.

 

[Bjorn]

References please.



But you haven't shown any in-room measurements of the Beolab 50 in the same positions and rooms for comparison?


Yes it would, and before that evidence is presented you can't state that "The in-room response of a speaker like Vera Audio Coherence 12 is a lot better [than any cardioid dispersion speaker]".



This is not how this forum works. You made a claim. Burden of proof is on you to back that up with reasonable documentation and data.

I don't need to compare the Beolab 50 to the VA Coherence 12 in the same position to know that. I have measured the Beolab 50 sufficient to know the following:
1. It suffers from a floor bounce, 2. Is suffers from some major diffractional issues in the treble,. 3. It's tuned with an elevated treble and with elevated deep bass
The Vera Coherence 12 doesn't have these issues and is tuned neutral as oppose to the Beolab 50. The Vera Audio Coherence 12 will never measure how the Beolab 50 did in the listening position or at several other places. That's simply not possible. 2+2=4

I was referring to the Vera Audio Coherence 12 vs the Beolab 50 in that comment. And it measures a lot better due to the reasons in the former paragraph. When it comes to several other known cardioid speakers I also know based on their design that the Coherence 12 will measure generally more even in-the room, but here the difference will be smaller. Knowledge about speaker design and acoustics and experiencing is sufficient here for me.

We can turn this around, can't we. What evidence do we have that cardioid actully measures flatter and especially below the Schroeder frequency? There's isn't really any studies that gives clear support of this. And did you see the measurement of the Kii Three vs the Phantom? The cardioid has more or less exactly the same frequency deviations as the Devialet Phantom with that position. Shouldn't we have seen something different here if the cardioid was superior?

What we do know for sure is that with cardioid we get a fairly even directivity with a speaker with a small footprint and slightly less reflected energy vs speakers with 180° directivity. To truly battle room modes we need something like multiple subwoofers, use phase cancellation or apply acoustic treatment. They all work and have their pluses and minuses.

 

[sigbergaudio]

We can turn this around, can't we. What evidence do we have that cardioid actully measures flatter and especially below the Schroeder frequency? There's isn't really any studies that gives clear support of this.

Personally I don't think I have ever made that specific claim.

EDIT: I have said that it will reduce SBIR effects, so I guess that is indirectly that claim.

And did you see the measurement of the Kii Three vs the Phantom? The cardioid has more or less exactly the same frequency deviations as the Devialet Phantom with that position. Shouldn't we have seen something different here if the cardioid was superior?

It's hard to comment on without knowing the room or situation. The Kii Three and the Phantom are vastly different designs, so I think the only thing we know for sure from those in-room measurements is that in that specific situation the room influence dwarfed the differences of the speaker design. We have no real way of knowing how this would have been different if we dropped in one of my designs, your designs, the Dutch&Dutch 8C or any other speaker. As I am sure you can agree, an individual in-room response isn't much data.

 

[ssashton]

It would be beneficial not to place both speakers in the corner where it drives the maximum number of modes. It puts 99% of the room inside the front radiation pattern and leaves little space around the speaker to develop a null.

 

[sigbergaudio]

While you can see differences in the on-axis response, I think there are other more subtle effects of a cardioid system like a cleaner sound and larger and improved soundstage. This is a consequence of reduced energy in the 90-180 degrees angle and thus reduced reflections, not necessarily visible as huge changes in the on-axis / reference-axis response in-room.