Beolab 5 - Four Questionable Technologies

Steuspeed,

You can't change amps, cables or tubes. Many in this hobby enjoy the challenge of upgrading and tweaking their system to their taste.

I suspect once I get a really great system that I will be happy to just keep it for a couple decades. I don't see myself tweaking it or swapping gear. I would imagine that in a couple decades there will be something significantly better which I will consider.

However, in twenty years, if I am alive I will be 75, and I'm not sure how good my hearing will be then...

Hi Hdomke,

My post above focused on what I believe is an under-appreciated aspect of loudspeaker design, namely what sort of reverberant field the speaker sets up, and its effect on timbre. I also place a high priority on a wide listening area.

Two things go into getting good sound over a wide area. First (and imho most important) is that the tonal balance hold up well for listeners who aren't in the central "sweet spot", and second it would be nice to still get some semblance of a soundstage from off to the side.

With a speaker like the Beolab 5, the tonal balance will be good throughout the room because the spectral balance of the first-arrival sound changes little if any as you move around the listening area. The imaging will be best up and down the centerline, but will still be better than average from off-center.

The ear localizes sound by two mechanisms: arrival time and intensity. For an off-center listener in a typical setup (conventional speakers with little or no toe-in), the near speaker of course wins arrival time, and it also wins intensity because as you move off to the side you're moving more on-axis of the near speaker so you're getting more high frequency energy from that speaker. With the Beolab 5, I think that there would be relatively little difference in intensity between the near and far speakers, so the image would still shift but probably not as much as with most speakers.

A technique I use with more directional speakers (90 degree instead of 180 degree pattern) is to toe them in severely such that their axes actually cross in front of the listening position. With this geometry, as you move off to one side the near speaker wins arrival time but the far speaker wins intensity, because you're now more on-axis of its tweeter. As a result, you still get a decent soundstage from well off to the side. I first heard about this technique from the writings of E. J. Jordan, and learned how to implement it using a waveguide speaker from Earl Geddes.

As far as speakers that imho do a exceptionally good job with the reverberant field and therefore tend to sound natural and be non-fatiguing (assuming they don't have other problems), I don't want to wax overly commercial here - some of these are speakers that I have chosen to peddle:

Omni or semi-omnidirectional: MBL, Wolcott, Ohm, Duevel, Shahinian, Morrison, and Mirage.

Wide, uniform monopole pattern: Beolab 5, the imho classic (and sadly discontinued) Snell Type A, Amphion, SP Technology, KEF Uni-Q, smaller Tannoys, DCM Time Window, Pioneer TAD home speakers, some Gradients, two-way Gallos, and to a certain extent many three- or four-ways that have a small diameter cone or dome midrange. Floyd Toole of Harmon Kardon (makers of Revel and many others) advocates this sort of radiation pattern.

Bi-directional with good reverberant field response: Magnepan, fullrange SoundLab, Apogee, Omega Acoustics.

Fairly narrow monopole pattern with good reverberant field response: Classic Audio Reproductions, PiSpeakers, Altec model 14 and model 19 (both discontinued), high-end JBL hornspeakers, big concentric Tannoys, GedLee (or Audio Intelligence - presently not distributed in the US), some Gradients, Emerald Physics (dipole at lower frequencies).

In addition, I build speakers that would fall into one or two of these categories. And no doubt I've left out many worthy contenders.

In general, the wider-pattern speakers out of these tend to be more demanding as far as room size and set-up goes. They also tend to sound more rich and enveloping, like you're sitting near the middle of a concert hall - whereas the narrower-pattern ones have a presentation more like you're up near the front of a jazz club.

By the way, thanks for the links you provided. Peter Aczel mentions the power response of the Beolab 5, and "power response" means "summed omnidirectional response" - so this includes the reverberant field. It's different wording (and a slightly different focus) in talking about the same thing.

Duke

B&O is not an audiophile directed product. It's a high end lifestyle product. It's aimed at a person who wants high quality sound, great looks and ease of operation and setup. I suspect that the typical B&O buyer enjoys music just as much as any audiophile, but unlike the audiophile they keep the same components for years without any changes.

When you go with a system like B&O you are pretty much locked into the brand. You can't change amps, cables or tubes. Many in this hobby enjoy the challenge of upgrading and tweaking their system to their taste. You pay a lot for the B&O look and style. They may perform very well, but there is a lot of other gear out there too. Other speakers with wide radiation patterns you might check out are Ohm, MBL and Gallo. Meridian is another company that builds everything into the speakers. I sold Meridian for years and it performed very well. However, for the same or less money you could build a system that would kill it. The Meridian buyers were usually more interested in the technology and equated that to better sound. Just because it is digital, does not make it better. Digital is an outstanding way to preserve data, but what ultimately comes out of your speakers is analog.

With regards to #4 i believe the digital ICE amps are found in other speaker products for example the Von Scweikert VR9 and VR11

AI

Duke,

In my opinion it's not the only speaker likely to have these characteristics.

What other speakers do you thing would have these characteristics? What other speakers should I be listening to if budget is no limit?

Thanks for your thoughts on reverberant energy. You seem to think it's primary advantage is that the sound would have a more natural timbre. I thought the key advantage was that the "sweet spot" would be a much larger area. This would give the listener(s) room to move around and still hear the music at it's best.

After you audition the 5's track down Wilsons for similar money and I think you will find B&O is not in the same musical universe

Zenblaster, funny that you should mention the Wilsons. This week I did extensive listening to a pair of Wilson Sophia speakers.

The Wilson Sophia's have the best sound I have had the privilege listening to (so far). I will audition the Beolab 5 this week with my friend that owns the Wilson Sophia's. He remains skeptical, since B&O is not considered an Audiophile brand. Neither of us have heard the Beolab 5 before.

However, if I go with the Wilson's I'm not sure I would save money. With the Beolab 5 I can connect the CD Transport directly to it with no other electronics. With the Wilson's I will need to also buy a Preamp and an Amp and all the cables.

I haven't heard the B&O Beolab 5 yet, but seriously doubt the lenses are mere marketing drivel. They address a problem that most loudspeakers have.

Briefly, very few loudspeakers generate a reverberant field that has approximately the same spectral balance as the first-arrival sound. This matters because the ear derives timbre not only from the first-arrival sound, but also from the reverberant energy. Driver beaming is the main culprit; it affects more than just the high treble. For example, in a typical loudspeaker when we cross over from the midwoofer (which is beaming) to a small tweeter, the radiation pattern flares out again and we have excess reverberant field energy in the lower treble region compared to the rest of the spectrum. Under most listening conditions, such off-axis response anomalies are audible and detrimental.

The lenses used in the Beolab 5 address this issue by reflecting the midrange and tweeter's outputs uniformly over a 180 degree horizontal angle. As a result, the reverberant energy has very nearly the same spectral balance as the first-arrival sound. This contributes to natural timbre and long-term fatigue-free listening.

Now I might quibble about the width of the radiation pattern used in the Beolab 5, but imho getting the reverberant field right is a fundamental requirement for natural timbre and something that relatively few loudspeakers do well.

Note also that DSP correction works best with a loudspeaker having a uniform radiation pattern. You see, DSP corrects for the microphone location only; if your speaker has an on-axis dip but an off-axis peak at a certain frequency, boosting that frequency to equalize the on-axis response would be a step in the wrong direction. DSP cannot correct the radiation pattern - it works best when uniform radiation pattern is an innate characteristic of the loudspeaker.

I would expect the Beolab 5 to sound very natural when set up correctly, and not be fatiguing over the long haul. In my opinion it's not the only speaker likely to have these characteristics.

Duke
dealer/manufacturer

I always thought of B&O as Bose for those with an additional digit in their tax return. So much r&d $$ spent on style and advertising at the expense of what?
After you audition the 5's track down Wilsons for similar money and I think you will find B&O is not in the same musical universe, they are stunning looking though. BTW there is a new set on EBay for 8k if you are so inclined.

Hdomke, there are two pairs on Ebay right now, for considerably less than $18k. FYI.

There was a review on this speaker a couple years ago

Yes, one particulary rave review was in the Audio Critic:
Audio Critic Review

#1 sounds like typical marketing drivel.

I agree, but what if it is real? It sure seems like a good idea in theory. I gather that the research behind the was developed by an American, Dave Moulton. Here is an article by him: High Frequency Dispersion

Of course and as always, you need to listen to them in your room if at all possible.

Yes, I plan to go to a B&O showroom this week to listen. As they say, the proof is in the pudding.

What are they asking for these speakers currently?

$18,000 US

There was a review on this speaker a couple years ago - I forget which magazine, but I recall it as being reasonably positive.

Technologies 2 and 3 in your list are reasonably well established. Several manufacturers have included #2 in their speaker offerings, though not necessarily so automated, but typically with positive results. #3 is usually done outside the speaker (see Tact Audio for an example) - done properly, it's a great thing, IMO.

Digital amplification (#4) is starting to become more and more common, with varying results. Presumably, the best results would come from embedding the amps in the speakers and match them to the specific drivers, as this model does. But, there are probably as many examples (or more) of bad results as good, which the technology continues to develop.

#1 sounds like typical marketing drivel.

Of course and as always, you need to listen to them in your room if at all possible. If the array of technology presented lives up to its potential, you'll have great sound in a package that is very compact. The downside is that if you ever decided you wanted to upgrade your amps, you can't, but that quite possibly would never be an issue.

What are they asking for these speakers currently? At one point, it was $25K, but it seems like they maybe came down in price.