Sugg. Retail: $3998 pr (CAN)
Size: 42″H x 8 3/4″W x 18″D
Distributor: Evolution Audio Inc.,
580 Granite Court,
Pickering, Ont. L1W 3Z2
(905) 839-8041 FAX 839-2667
(Reprinted from the Winter 1998 Audio Ideas Guide)
As part of the Synergy Series and the Premiere group of speakers, the Klipsch KSP-300 seems a little over identified, sort of like all those women going around with three names in the wake (and some wake, too) of Hilary Rodham Clinton (reminds me of Hickory Dickory Dock; I guess Monica’s problem is that she doesn’t have a middle name). Anyway, before I slide off into total irrelevance while hardly into this review at all, I should note that Klipsch’s Canadian distributor, Evolution Audio’s Saxe Brickendon (he doesn’t need three names) described the KSP-300 (which is just what we will call it for simplicity) as, “Not your grandfather’s Klipsch!”
And he’s right, of course. Having listened with delight recently to a pair of the mighty and effortless Klipschorns upstairs at American Sound, I was intrigued to encounter these new tall, slim, deep speakers. In fact, these may be the only characteristics they share with the legendary Paul Klipsch and his seminal speakers; he’s now in his mid 90s and still standing well over 6 feet tall.
There is, however, one trait the KSP-300 does very much share with other Klipsch speakers, and that is the high sensitivity typical of the brand, at 94 dB/watt/metre, using a Tractrix horn on its tweeter to this end. However, it is the first Klipsch model in my experience with a powered woofer/subwoofer built in, and is part of a new series that addresses the home theatre needs of the 90s in a very specific manner. It even has an extra LFE (Low Frequency Effects) line input to the sub section with its own level control for use with Dolby Digital systems. The driver is a side-mounted 12″ “resin re-inforced fibre composite material” “long-throw excursion” woofer with “santoprene surround”, driven by a 150-watt amplifier.
The mid-bass driver has a cone made of mica-filled polypropylene for light weight and rigidity, crossing over to the tweeter at 2.6 kHz in a 2nd order 12-db/octave configuration. The tweeter is a 1″ “polymer diaphragm compression driver” with ferrofluid around the voice coil. According to the poop sheet, “the Tractrix horn design virtually eliminates internal reflections within its operating range; as the sound waves expand through the throat and flare, it follows the natural expansion of the waveform while maximizing dispersion control.”
The cabinet is heavily braced internally and sectioned so that both mid-bass and subwoofer sections are completely sealed. With the electronics and a very substantial enclosure, each KSP-300 weighs in at 78 pounds. Visually, it’s a very attractive speaker, the “West African Mahogany” finish stunningly luminous, making my Veritas (also mahogany, but probably plain old Ontario mahogany) look quite utilitarian by comparison. And the gently curved top is a nice retro touch that harkens back to another era, a time when craftsmanship encapsulated even a radio. See the cover of our A/V Almanac for confirmation; speaking of that cover, and nostalgia, I suggested to American Sound’s Angie Lisi a few months back, only partly in jest, that she needed the D-Box Mammoth subwoofer between her Klipschorns to really get bass. She wasn’t convinced (by the way, the Klipschorn made its debut in 1946, and is the only high fidelity speaker that has been in continuous production for over 50 years).
And here we are, well into this review with nary a mention of measurements…or sound.
Be patient, dear reader, we have only just begun our explorations. Before getting to these things, I just want to comment further on the business end of the speaker, its rear panel, shown in a line drawing here. All inputs and controls are on the black metal amplifier panel, with Level and LFE Level controls at top, RCA inputs and outputs (high-pass to subwoofer) below, and the speaker inputs farther down; these latter are doubled for bi-wiring or bi-amping, and are plastic-nut, gold- plated types. There is also a slide switch that allows you to have the amplifier come on automatically with the presence of signal, or stay on all the time, the option I preferred.
Usually, I listen to a speaker after measuring it, but in this case the process was reversed, a listening session ensuing after the Klipsch folks, the aforementioned Saxe and Allan Feldstein, National Sales Manager, Canada, helped me set up these large, quite heavy speakers. I wasn’t surprised, therefore, by the excellent curves that appeared in my LMS system the next day. The KSP-300 pair had shown smooth, wide frequency response, with powerful, deep bass, with a little extra energy in the mid and upper bass region. These speakers were also notable for a complete lack of any horn coloration in the midrange.
Looking at the curves from the top, we see a very linear response from about 300 Hz up, the Pink Noise Sweep (PNS) and Summed Axial Responses matching very closely, with slightly more variation in the SAR’s midrange, something I’ll expand on below. The very top of the range tends to roll off above 10 kHz, but the overall response is +/-2 dB or better from about 300 Hz up, excellent smoothness. This can also be seen in the quasi-anechoic on-axis measurement below, the KSP-300 looking better through the crossover region between 2 and 3 kHz than many speakers we measure.
In the axial curves at bottom, we can note a characteristic of horn-loaded tweeters, a uniformity of response across the listening window, with an appreciable dropoff in level beyond the listening axis. In other words, the Tractrix horn provides very even dispersion across its range, as does the cone midrange driver (and they are very well matched acoustically), and they do so over an axis of beyond 30o. But the flare of the horn also controls diffraction very well, and this has the advantage of making the speakers easy to set up with respect to side walls, and able to image very well, since secondary reflections are not coming off the baffle edges nor off the walls. The narrow baffle also helps in this respect. The 60o response can be seen to be down 6-to-8 dB relative to that in the listening window.
And now to the lower end of the frequency range. The amplified subwoofer is more than just a sub: its response extends to 150 Hz, which is not all good news. Since there is no low pass adjustment, I was unable to tame the bump between 50 and 150 Hz. When we had set up the bass level by ear for the listening session, we’d ended up with a setting at about 11 o’clock, which resulted in the measured curve at top. The one below that was a compromise between flatness and extension at about 9 o’clock: if I had set the control for flat response at 100 Hz, much of the deep bass energy would have been lost. Since this is a relatively easy thing to fix, I suggest to the Klipsch engineers that they address it with either a 3-position slide switch (60-100-150 Hz) or an additional rotary control for subwoofer upper crossover adjustment.
In listening, though, it was not a huge deal, the bass a little fuller with plucked bass and cellos, but the musical balance very neutral across the rest of the range. There’s a lot to be said for efficiency, these 94-dB speakers having an effortlessness that has always been a Klipsch hallmark. They played loud and clean, and offered a very sweet treble that was full of microdynamic details. I would call the KSP-300 the best speaker from this manufacturer I’ve heard in years, and as uncoloured a horn tweeter as I’ve ever heard.
And I’m tempted to offer an anecdote here. In Las Vegas this year I stayed at the Luxor, which to my delight, has an IMAX 3D theatre. One evening Newform Research designer John Meyer and I went to see a movie, and as the opening narration began from the speakers hidden behind the screen, John said quietly as he heard the male voice speak, “horns…” Now, when I sit down to listen to the Newforms in my home theatre, I don’t murmur, “ribbons”, but his speaker-designer ears had immediately picked up the midrange colorations of the big theatre horns. But there was none of that to be heard from these speakers, a particular strength being their smooth and natural character on voices and solo instruments. Indeed, these are not your grandfather’s Klipsches!
Before I forget (and almost did), the impedance and electrical phase measurements are also excellent, with an impedance low of 5 ohms in the upper bass and a high of about 16 in the treble and 20 ohms at 80 Hz; the electrical phase below is notable for its smoothness. These speakers are a very easy load for any amplifier of virtually any wattage. Even single-ended fans can hear all that lovely 2nd harmonic distortion (detail!) in all its glory at high levels. Seriously, I did listen to them driven by the 18-watt KAB Souvenir (review forthcoming) solid state single-ended Class A amp, with nicely musical results. This is just about the easiest speaker to drive in our experience.
Elegant in both look and sound, the former quite art deco and the latter very up-to-date, the Klipsch Synergy Series Premiere KSP-300 (whew!) is to my ears, the best speaker I’ve heard from this company since the mighty Klipschorn (and it has a bigger brother, the KSP-400), and whether used as part of a home theatre system, or as a stereo pair can offer exceptional and effortless musical reproduction.