Mar 06, 2004
I was fortunate to be extended an invitation by a
to attend yesterday’s Music Technology divisional meeting, where
Dave Moulton gave a presentation on B&O’s
Beolab 5 speaker. The
presentation was followed by a question-and-answer session, and
an hour-long listening session. I missed the first part of the presentation,
but I was able to hear about some of the technologies behind the speaker.
Quick notes from the presentation:
- The computer used for the calibration is firmware upgradeable via
an RS232 port. In response to a question, Dave mentioned that there is
no real-time output from the computer, so audiophiles can’t tweak settings on
- The microphone used for calibration is located at the bottom of the
speaker, and moves to 3 different positions to determine the driver performance
and the room performance. Based on the demo, the speaker appears to
use warble tones to perform the calibration (presumably to minimize
standing waves). Dave indicated that 10 Hz to 300 Hz test tones are
generated for the calibration.
- The computer compensates for thermal compression characteristics
of the driver, so the speaker performance should not degrade as the
drivers heat up during long/loud listening sessions.
- Each speaker contains 4 Class-D amplifiers to power the bass, mid-bass,
mid-range, and treble speakers. Total rated power is 2500 watts per
- The speakers are rated at 108 dB per pair at 10 ft.
- I had a chance to ask Dave about the possibility of
Sausalito Audio Works
or B&O making the
acoustic lens available for the DIY market. Dave said that it
was considered, but unlikely to happen soon (if ever). The acoustic
lens apparently requires a fair amount of engineering and cross-over
work to properly integrate with the tweeter and the rest of the system, so
in its present form it may not be suitable for DIY’ers. Too bad.
For the demo, we listened to a variety of music including pop (Paula Cole),
Jazz (Count Basie), gospel, hip-hop (Outkast), classic rock (Led Zeppelin),
and classical (Mahler’s 3rd Symphony). My impressions from the listening session:
- The Beolab 5 has, by far, the best bass response I have ever
heard in loudspeaker. I will admit that I was somewhat
of the room correction function. Frankly the Beolab 5’s
room calibration system works, and works well.
- The treble response was airy and detailed, without being overly
harsh or bright. In short, very good, but I think I still prefer the
sound of ribbons.
- A pair of Beolab 5’s had absolutely no problem in filling
the (approx) 50ft by 50ft by 20ft
David Friend Recital Hall
with sound. The bass and soundstage were fairly uniform throughout the hall,
despite the difficult conditions in the hall.
- Those suckers get loud! The audience (mostly composed of
recording engineers I presume) kept asking Dave to crank up the volume, and
at one point I would guess the sound level as well over 90 dBA on average, with
peaks approaching or exceeding 100 dBA. The speakers showed no signs of
stress at all, and my ears gave up before those speakers did. (BTW,
given how comfortable the rest of the audience appeared to be during the
loudest levels, I think everyone in that room needs to get their hearing
- Hip-hop fans might be disappointed in the bass response. If the
track has real low-end, the Beolab 5 will shake the room, but most hip-hop
tracks seem to be mastered for playback on bandpass boxes that
accentuate the 50 to 60 Hz range. The Beolab will precisely reproduce
bass, but it’s not going to emphasize the mid-bass like some ported home
and car audio speakers.
- My only critique: while the speakers did project a wide
soundstage, I was disappointed in the imaging. While listening
to very good speakers, you can usually close your eyes, and point out
the piano, vocalist, etc. I couldn’t with the Beolabs. For example, during the
a capella portion of Paula Cole’s “This Fire,” Paula seemed
to be about 10 feet wide. Granted, I was never able to listen to the
speakers at the “sweet spot,” and the recital hall was challenging
to say the least. I may need to listen to these speakers in a more suitable
In short, while these speakers are not quite the best I’ve ever heard (that
honor goes to the Wilson Watt/Puppy),
they’re definitely among the best. I highly recommend that every audiophile give
them a listen. The bar has certainly been raised, if not for overall speaker
certainly for bass performance.