Lawrence Audio Double Bass Speakers Review

The Sound: General

There is a school of speaker design that ascribes to the notion that a speaker should be constructed like a musical instrument. Such speakers are usually constructed of wood (typically “tone wood”), so chosen for its resonant properties, and typically provide a warm, luxurious sound (often described as “musical,” a term to which I vehemently object, but that is a discussion for another day). Others (myself included) view a cabinet resonance, no matter how pleasant or euphonic it might be, as an unwanted and undesirable coloration. I raise this issue because by looking at the Lawrence Audio speakers, or learning of their names, one might conclude that they fall into the former camp, but this would be an erroneous conclusion. The Double Bass speakers have a relatively non-resonant cabinet; their overall shape is not designed to “sound” like a musical instrument but rather, to reduce internal standing waves; as noted above, their uppermost section (i.e., that housing the ribbon tweeter and AMT midranges drivers) is narrow so as to minimize diffraction. As far as I can tell, the Double Bass is designed to be an accurate transducer of the signal fed it. Accuracy is often equated with “analytical,” though in point of fact an analytical sound is more likely to result from particular inaccuracies. But to the point, the Double bass speakers are not analytical, though neither are they warm; I would describe their sound as being closer to neutral than to either of those other descriptors.

The Sound: Specifics

As noted above, each Lawrence Audio Double bass speaker contains two AMT midrange-tweeters. AMT drivers differ from other more familiar drivers, such as moving coils, true ribbons, planar magnetics, and electrostatics. The following description is from Wikipedia:

The AMT moves air in an augmented, semi-perpendicular motion using a folded sheet (made of polyethylene, polyester or polyimide), structured around a series of aluminum struts positioned in a high-intensity magnetic field.

…

The diaphragm pushes back and forward from itself in a physical motion similar to that observed when an accordion is pushed in and pulled out to pump air though the reed chambers, albeit over an exceedingly smaller motion range.

The result is a dipole driver with an extraordinarily rapid response rate, enabled by the extremely low mass of the polyester driver and the far smaller distance it travels on each “swing” compared to a dynamic driver. In this technical respect, it shares characteristics with the electrostatic driver.”

Wikipedia hit the nail on the head in describing the AMT’s sound, which not surprisingly reflects (pun unintended) the sound of the Lawrence Audio Double bass speakers. In conjunction with the three ribbon tweeters (two in front, one in back), the Lawrence Audio Double Bass speakers do indeed have an electrostatic-like quality in the upper midrange and up. The sound is notable in terms of its speed, clarity, and transparency. As is true of any high quality midrange driver, voices benefit the most. Through the Double Bass speakers, voices have a tangible, life-like quality that ranks amongst the best I have heard. The AMT also really shines with acoustic string instruments, which are reproduced with great “snap” and presence, and as with voices, with a superb natural quality. Some ribbons can get a bit edgy, but such was never the case with the Lawrence Audio Double Bass speakers. The ribbon tweeters have tremendous extension with no apparent break-up or distortion. If I was to lodge a complaint it would be that the uppermost frequencies could at times sound a bit thin, almost as if they didn’t have quite enough oomph to keep up with the two AMTs; perhaps I’d prefer them raised a dB or two. But this was a minor quibble and moreover, is more along the lines of an error of omission, which in audio is almost always preferable to an error of commission. It most assuredly was not a deal breaker.

In terms of macrodynamics, the speakers were exciting and never sleepy (a complaint I have with many speakers), though not surprisingly, their dynamics were not in the same league as the Sadurni Acoustic Staccato horns I have in for review. But lest I be misunderstood, the Double Bass speakers perform quite well when compared to other dynamic driver speakers in terms of power and the ability to “scale up” when the music does.

Next up (or is that “down”?) is the bass. In many respects, bass is the most complex part of a speaker to design, as it is so critically dependent on the cabinet design, and the room in which the speaker is placed. In addition, every designer must carefully balance bass extension, cabinet size and efficiency (per Hoffman’s Iron Law), and must choose a system Q so as to favor extension or “tightness” (i.e., over- vs. under-damped design), or something in between. Speakers based around ribbons and/or AMT drivers have an additional problem, namely that of getting those drivers to integrate with “traditional” cone woofers. (The same is true for electrostats and magnetoplanars.) In simple terms, cone woofers have trouble “keeping up” with the aformentioned drivers, presumably due to differences in transient response, dispersion, and distortion profiles.   After spending a fair amount of time with the Lawrence Audio Double Bass speakers, it is clear that Lawrence Liao reached superb compromises. First and foremost, the bass frequencies blended quite well — better than I expected, if truth be told — with the mid- and upper frequencies. Although there was a sight sonic discontinuity, I often had to listen closely to detect it, and it was never distracting. The bass itself was of very high quality. The specifications list the frequency response as being 24Hz-40kHz , though no + dB is listed. My sense is that the speaker is flat to perhaps 30 or 35 Hz and while it does not punch you in the gut the way a speaker with one or more 15” woofers will, it was deep and powerful enough for the vast majority of music. One could of course add a subwoofer for the last half octave or so, though I never felt any urge to even consider doing so. The design favors quality over quantity — the bass is fast and articulate, with considerable detail and nuance. I never would have guessed that it was a ported design, which reinforces the notion that implementation is equally – if not more – important to the type of design. I’m not sure how Lawrence engineered the port (as noted above, the speaker is ported out both sides, near its bottom), but he clearly did an excellent job.

I have never been a big fan of mini-monitors because they lack the “power” and extension I find necessary to convey the emotional content of much music. That said, larger speakers often call attention to themselves in a way that mini-monitors do not, reminding the listener all too clearly that one is listening to a speaker, rather than an actual musical event. It was thus with an unexpected pleasure to find how well the Lawrence Audio Double Bass speakers did the disappearing act, which I attribute to the well-executed cross-over, the superbly designed cabinet, and especially the narrow dispersion, which allows the listener to hear more of the direct arriving sound and less of the reflected sound from various room boundaries. (With regard to the issue of dispersion, see my review of the Sanders Sound Model 10 speakers and my interview with Roger Sanders). But whatever the reason(s), the bottom line is the Double Bass do not call attention to themselves, and throw a wide and deep soundstage with each instrument in its own clearly defined space, which collectively aid considerably with the illusion of hearing live music.