Beolab 5 - Four Questionable Technologies

Design has much merit and is well thought out. My problem with a all digital amped, DSP loudspeaker is time. We all know how well computers age will this loudspeaker be fairly worthless in the future like a old computer or DAC? Will advancements in dig amps and DSP make it primitive in the near future? While folks who bought conventional loudspeaker designs can still upgrade amps etc. Will the digital section hold up as well as the transducers or if it gets a voltage spike is it toast?

Hdomke,

To get a sense of soundstage go to a nearby high end dealer and ask him to demo any speaker that he feels will impress with its soundstage. Most will be able to find a recording and system that will make it very clear what the term means. Ironically, some people (justifiably) point out that you rarely hear this type of spacial illusion at a real performance. Usually, that is quite true. Yet, the quality in a stereo is critical to me. YMMV.

BTW, I can't state with confidence that the Beolab 5 doesn't image (soundstage) well. Few speakers will do so when jammed into corners. Also, the congestion I heard at demo may be due to distortion generated by the speaker as loudish, complex musical passages tax the drivers and force them to misbehave. Or, as I noted, it could have been the set-up or some defect. I was not listening at crushing levels and I found the problem instantly identifiable. I find it hard to believe that neither of the reviews linked to this thread mentioned the problem, so I'm inclined to believe that it was unique to the Beverly Hills set-up.

OTOH, Shadome may have heard a similar problem. It's quite possible that the wide dispersion pattern makes distance from the side walls critical to best results. A speaker which pours so much energy off axis may sound congested due to early side-wall interactions. Shadome, how was the set-up at your demo?

To sum up, I left the demo feeling like I knew very little about the speaker, other than buying this speaker would require an in-home demo and a large listening room. I don't know if B&O would accomodate such a request.

Good Luck,

Marty

I gather you are referring to the lack of the illusion of the musicians laid out properly in space in front of you.

Yes Exactly.

I wonder if that flaw is the price one pays for the benefits of the Acoustic Lens technology? This technology allows for a much wider “Sweet Spot” but perhaps the sweet spot we get isn’t as sweet as it would be in a more conventional speaker.

No. Other conventional box speakers can have wide dispersion and hence a large sweetspot AND image like there is no tomorrow. Like Marty - I fully expect a vocalist to appear as a solid single image in a mix - clearly positioned - not dispersed vaguely in front of me. When a duet is singing I can clearly hear that they are positioned two feet apart in the soundstage when they are mixed that way. I felt that the Beolabs hinted or gave glimpses of precise imaging in certain sounds or vocals but did not do so solidly all the time - much of the time there was a certain diffuseness to everything)

To help accomplish this{Soundstage}, do Audiophiles always try to sit at precisely the right spot when they are doing active listening?

No it is not necessary to sit at precisely the right spot on widely dispersive high quality speakers such as you can find at this price. Location of sound is NOT all about volume level in fact this is a misconception propagated by the industry to try and sell more center channels. You can have one speaker 10 DB louder than the other and yet the sound can come from directly between them....it is timing that tells us the location much more than volume level (most people are unaware of this). Of course the image will move slightly as you sit in front of one speaker or the other but the soundstage should not collapse. Also if timing is messed up or poor then volume level will weigh more heavily in how you determine the position of instruments in the soundstage.

You both also complained about “congestion/compression” and “congested/cluttered in upper midrange”. Please help me understand. I’m guessing that you mean that in parts of the music the differences between instruments might blur, which makes it hard to differentiate or even identify the instruments?

Yes is was "blurred" or not razor sharp clear in the upper mid range. It sounded "softer" or less piercing and less harsh then I would expect from natural sound. It made for a less exciting or involving sound as there was no "edge" to leading instruments or vocals. If this is indeed the 3' Vifa Dome Midrange driver that is being used then it only has a linear Xmax of +/- 0.5 millimeters - which is not much better than most tweeters (i.e. terrible) - this dome midrange will compress all to easily if driven too low in frequency which means that either you lose lower midrange energy from compression at high levels or you need to crossover very high into the midrange with the 6 inch woofer - either way this concerns me but it is conjecture as I have no proof that is definitely is the 3" Dome Midrange from Vifa that Beolab 5's are using. (The midrange dome on my speakers has an Xmax of 3.0 mm or six times more linear excursion than the Vifa mid - so I get more than enough crystal clear midrange energy before non-linearities/compression sets in)

I spent a couple hours in the afternoon listening to the B&W 800Ds in a very fine listening room. The words that kept coming to my mind were “natural” and “real”. Perhaps those are the speakers I will buy…

Yes do buy these over the Beolab - far better, IMHO. This is a fine speaker. A bit hard to drive but with the right SS amplification they will sing. The large midrange tends to "beam" slightly in the top of the midrange (less wide dispersion or even sound field from 2 to 4 Khz) and they come on a bit strong around 4 Khz (when the widely dispersive tweeter kicks in) - however this is nitpicking - this is an absolutely outstanding speaker. World class.

It would seem to me that the ideal next step would be to get the Beolab 5s and the B&W800Ds into my listening room at home, preferably at the same time for some extended A:B comparisons.

I am not sure I agree but it is your taste that counts not mine. (As you know by now I think the 800D is a far better speaker, however, I also think you owe it to yourself, at this price, to audition a few other speakers. It would be worth the price of a weekend trip to CES just check out other designs, at your price point.)

Also, the congestion I heard at demo may be due to distortion generated by the speaker as loudish, complex musical passages tax the drivers and force them to misbehave. Or, as I noted, it could have been the set-up or some defect. I was not listening at crushing levels and I found the problem instantly identifiable.

Marty, I agree with you. It was immediately identifiable. In my audition they were about three feet from the corners - so to me the congestion was from the speaker not the placement. I too felt that taxing passages at higher volumes stressed the midrange, as the lower/middle mid range seemed to get buried by the bass and treble. However, like you say, it is impossible to be "conclusive" about this in a short listening test with a Sales Rep over your shoulder. All I can say is that it was pretty obvious to me, although I am used to a rather forward midrange presentation so my impression could be influenced by my reference. In any case, there is no way I would be reaching for the checkbook for this sound. So it seems we heartily agree. I would add that there is no way I would bother to get these in the home (given my tastes for precision - they just don't suit me at all except for their impressive tight bass response).

Shadorne,

I just have a question for you regarding your audition of the BeoLab 5.

You said that the speakers were in a square-shaped room with glass on both sides and no acoustic treatment. How much space was there between the speakers and the side walls?

The reason why I ask is because of the design of the Beolab permits almost 180 degree dispersion throughout the treble and midrange, and the high reflectivity of the glass surfaces would undoubtedly play havoc with the speaker's ability to produce accurate imaging and soundstaging.

I've never heard the BeoLab 5 yet, but I am quite interested in hearing it for myself. So far my most favourable impression of an omni-directional speaker was a Morrison, but that's going back many years. My current speaker is the Merlin VSM-MM, so it would be interesting to hear firsthand how the BeoLab 5 sounds in comparison.

Aside from this, I just have to call you out on two claims you made.

1. "Other conventional box speakers can have wide dispersion and hence a large sweetspot AND image like there is no tomorrow."

It has to be clarified that any conventional front-firing box speaker will be highly directional the higher you go up in frequency. If you observe the lateral frequency response graphs published by Stereophile, typically for box speakers the treble frequencies from 10Khz on up will fall off rapidly the more that you move off axis. "Wide dispersion" in this case just cannot be compared to the dispersion characteristics of a true omnidirectional loudspeaker design, which means that special consideration is required for room positioning, in order to minimize early reflections that can cloud the sound and make it seem congested.

2. "No it is not necessary to sit at precisely the right spot on widely dispersive high quality speakers such as you can find at this price. Location of sound is NOT all about volume level in fact this is a misconception propagated by the industry to try and sell more center channels. You can have one speaker 10 DB louder than the other and yet the sound can come from directly between them....it is timing that tells us the location much more than volume level "

I would agree that your lateral seating position isn't overly critical for a box speaker with wide dispersion if you were only listening for tonality. However, I completely disagree with you that seating position does not matter if you are listening for imaging and soundstaging.

While it is true that the human ear perceives spatial relationships through detection of amplitude and timing differences in the sound that reaches our left and right ears, I think that your example is rather exaggerated, and isn't very helpful to Hdomke's attempt to understand how to optimize his ability to hear proper imaging and soundstaging.

A 10 DB difference in amplitude would make speaker "A" sound twice as loud as speaker "B". Thus if both speakers and the listener were positioned like points on an equilateral triangle, the centre image would be perceived to be shifted toward the side that speaker "A" is on. In practical terms, if you were listening to a vocal track where the singer is supposed to be situated dead centre, now the singer will sound like s/he is standing to one side.

In order to equalize the effect of the amplitude difference, you would have to significantly increase the spatial distance between speaker "A" and the listener, until the increase in arrival time and the attenuation in perceived volume of the sound coming from speaker "A" no longer predominates over speaker "B".

Should anyone auditioning speakers have to go through this? I don't think so. If you want to listen for imaging and soundstaging, then sitting in the sweet spot (equidistant between both loudspeakers) is essential in my opinion.