I pulled the trigger today on some new floorstanding speakers. Salk Sound has recently introduced a new speaker, the
SongTower QWT. It is a floor standing MTM speaker that combines two excellent
Seas CA15RLY 5¼" midwoofers, and a simply outstanding ¾" dome tweeter, a
Hiquophon OWII.
These are the least expensive speakers in the Salk line, but for me, a confirmed DIY guy (or so I thought), these "budget" speakers are the most I would ever consider paying for a commercially made high-end speaker. At $1,500 a pair, I think these speakers have no competition. There will soon be a home theater “Song Series” with a matching center channel, rear channel speakers, and a subwoofer. I hear that they may be announced soon.
Instead of putting these drivers in a sealed or vented cabinet, they come in a transmission line cabinet. Transmission line design, although it has been around for some time, was new to me. This cabinet design has always been said to allow floor standing speakers to exhibit greater bass extension than a vented design would normally allow. But some of these were difficult to build because they involved folded interior chambers. More importantly, a successful transmission line cabinet required trial and error and lot of luck. In contrast, sealed or vented cabinets have been well enough understood since the early 1970s that many plug-in math formulas exist to aid in their design. Until recently no similar method existed to predict or model the bass response of transmission line cabinets. Thanks to the pioneering work of
Martin King, this is now more easily understood and accomplished. Still, there very few TL cabinet speakers available commercially.
When I first heard the new MTMs, I simply could not believe that two 5¼" woofers could produce such bass. To say that "a transmission line cabinet allows a floor-standing speaker to exhibit greater bass extension than a ported design would normally allow" understates what I experienced. The effortless bass of these speakers seemed to defy the laws of physics. What's more, the sound differed to my ears, from that of either a low-Q sealed woofer or a properly designed ported woofer. Without a better way to describe it, a transmission line produces a third type of bass sound that sounds superior in quality and quantity.
The SongTower’s designer, described this exceptional bass response somewhat better than I can. “Martin King's scientific approach to transmission lines really has made the difference. And the benefits of his work aren't limited to bass quantity and quality. Before Martin King really figured out how to model TL's, this type of bass loading often generated higher order harmonics that severely colored midrange reproduction. That was a complete waste, since a long damped line held out the potential to dissipate the back wave from a woofer and reduce colorations over its operating range. Martin figured out how to achieve the bass benefits of TL loading while eliminating its negative effects in the midrange. As a result, a design that is optimized according to his calculations achieves superior bass and midrange clarity.”
These rather easily driven MTM speakers are flat ± 3 dB from 40 to 20,000 Hz. They have an 8" × 11.5" footprint, and they sound to die for!