Stand Loudspeaker Reviews

Herb Reichert reviewed the Klipsch Reference Premiere RP-600M II in August 2023 (Vol.46 No.8):

The grandest perk of being a reviewer is when sniffing through the grass leads me to a high-performance product capable of wide-ranging appeal at a price point that shouldn't scare anyone. In my sniffing, I have encountered a few products of this type, whose success I've applauded because it is so much fun to see legions of happy audiophiles united in their approval of a product so unusual that they may not have considered it had it not been ardently championed in the audiophile press.

Klipsch's popular flagship standmount, the Reference Premiere RP-600M, is exactly that kind of product, one that I am proud to have championed when it first came out.

In my March 2019 review I used descriptors like "responsive," "boogie," and "high-vitality." I observed how the RP-600M achieved its high PRaT quotient by slightly emphasizing the leading edges of notes, which in turn emphasized the beat and clarified the melody. The original was designed for high-engagement listening. The only sonic indications that I was listening through budget speakers were a moderate lack of soundstage width, some softness, and some light graininess and blurry focus in the crossover region.

Cosmetic tells were all of the plastic and vinyl variety.

While I worked on that review, I kept asking myself: What kind of audio manufacturer names their flagship standmount speaker "Reference Premiere" then sells it for only $549/pair? It seemed ridiculous.

So now Klipsch has updated the Reference Premiere RP-600M, adding a "II" to its name and $100 to its cost.10 Klipsch appears to have addressed each of the original's shortcomings.

The "II" costs $649/pair. Measured into a half space at 2.83V at 1m, the II is specified as 94.5dB-sensitive—slightly lower than the original's 96dB (footnote 1). At 18lb, the II weighs 2lb more than the old one did. At 16" H × 8" W × 13" D, the II is an inch deeper than the old. The II's redesigned conical-tractrix high-frequency horn measures 6.75" square; the original measured 5.75". This 18% enlargement brings the edge of the horn's mouth closer to the beveled top and sides of the speaker cabinet, which I imagine reduces horn-edge turbulence and dispersion anomalies, which could result in less blurring and grain.

There's more that's different in back than there is in front. Most obviously, the II's new biwire-ready binding posts are now made of sturdy, treated-aluminum alloy and sit on a luxuriously finished aluminum mounting plate. Cosmetically, both the tractrix-flare port and the binding-post mounting plate are now mortised flush with the cabinet—a subtle but elegant touch at this price point.

As soon as I began using it, I realized that Klipsch's Reference Premiere RP-600M II begs these questions: How exciting to use can a $649 pair of standmount speakers possibly be? What could a $10,000 or even a $30,000 speaker do that this almost-free Klipsch can't? Who wouldn't like this speaker?

I just finished reviewing TAD's $32,250/pair CE1TX standmount, which made a strong impression, giving me a refreshed picture of what today's state-of-the-art speakers are capable of. The chief thing I learned was how rarely I encounter a speaker with truly even in-room response in the 50Hz–500Hz range. On the rare occasions when I do, I am invariably impressed by how natural the speaker makes all recordings sound and how effective accurate tone and stable focus are at encouraging listeners to explore the broadest possible range of music.

This degree of even-handedness, particularly in the bass, is something I almost never encounter with moderately priced ported standmounts; even my sealed-box LS3/5a's struggle in this area. What's more, the RP-600M II's redesigned woofer, which Klipsch says sports Faraday rings and a larger voice coil, may actually lower distortion, especially in the crossover region. Klipsch's new woofer uses Lenz's law to lower distortion. The RP-600M II's voice coil motions induce currents in the Faraday rings, which, due to their opposite polarity, cancel stray electromagnetic fields generated by the motions of said voice coil, thereby stabilizing the flux field in the magnetic gap.

Similarly, high frequencies emerging from the RP-600M II's larger horn felt smoother and more refined, with less noise in the crossover region. I distinctly preferred the old Klipsches with their speaker grilles attached and the new Klipsches with them removed.

The combined effect of the revised horn and bass driver is to add weight, presence, and low-signal delicacy to the presentation. The new Klipsch is simply more refined-sounding.

Another thing rarely encountered in moderately priced standmounts is the ability to play in a responsive, lively, unrestricted manner with low-power, high-output–impedance tube amplifiers. For fun, because I could, I tried driving the new Klipsches with the 3.5W, 2A3 tube–equipped Elekit TU-8900 amplifier described in the July issue's Gramophone Dreams. With my favorite piano recordings and a pair of WWII-era, new-old-stock RCA 2A3s, the TU-8900 emphasized the RP-600M II's dynamics and good tone.

With the 3.5W 2A3s powering Musikalische Perlen (24/48 FLAC, Ars Produktion/Qobuz), the flute and harp of Les Connivences Sonores scattered angels in the space above my sound system and forced me to consider: How much more beauty and musical force would I (or should I?) be getting with a $10,000 speaker? I am listening in my little room with a $16,000 dCS DAC driving a $4000 amplifier powering speakers that cost $649/pair, and all I'm noticing are vibrant, expanding harmonics and full-tilt momentum. No soft bass or lean tone, no blurry focus or hard-edged distortion. No clipping-induced dullness. No distraction. Just easy-flowing tunes.

Lately, my brain is searching (so far without success) for some reality-based view of how sad or disappointed I should have felt when I switched from the $32,500/pair TAD CE1TXs to the Klipsch RP-600M IIs. Good as they were, when I moved on from the TADs I experienced no "sequence is everything" letdown. The IIs make all genres of music exciting to explore, and those excitements kept me rolling, one album to the next.

Listening with the Elekit driving the RP-600Ms, I was reminded of the time I replaced a silver-foil coupling capacitor in a $90,000 Audio Note (Japan) Ongaku amplifier and hooked the Ongaku up to my testbench speakers, which were Acoustic Research's "M1 Holographic Imaging" speakers. If I remember right, those M1s cost me less than $350/pair, new. When sound started coming out, I just stood there staring at the shelf space between them repeating "Are you kidding me?" What I experienced was so surprising that I dropped everything and moved the M1s out to the big room in my main system and started calling friends over to witness the most three-dimensional sonic projection and most naturally textured midrange ever. An ocean of reverberating atmospherics engulfed a huge, precisely mapped soundstage. The effect was spellbinding and unforgettable.

Remembering that made me feel guilty about using an amplifier that may be out of financial reach for many RP-600M II users, so I decided to conclude this Follow-Up review using a much lower-priced amplifier: the $125, 5W, class-A, Nelson Pass–designed "Amp Camp Amp mini" (review in progress). You can buy this amp's unstuffed circuit board and FET and MOSFET transistors from the diyAudio Store for $25 (footnote 2)! Then you can add the $100 ACA mini "completion kit," which includes everything else— line-mounted power supply, power cord, resistors, capacitors, heatsinks, and so on—everything except the chassis, which I didn't bother with. Voila! You are suddenly in possession of an extremely refined-sounding class-A amplifier.

As I plugged in the ACA mini, I wondered: How much less wonderful will the experience of a similarly powered but 30-times-less-expensive amp be? The best thing about expensive tube amplifiers is, if you've never used one you won't know what you're missing. Your screechy schoolmarm amp will seem just perfect—until you've been embraced by something more voluptuous.

Guess what? Paired with the RP-600Ms, this $125 DIY kit sounds fresh, luxurious, and voluptuous. It played Eleni Karaindrou's compositions for the 1998 film Eternity and a Day (16/44.1 FLAC, ECM/Qobuz) with a majority portion of the clarity, atmospherics, and tone-rich harmonics of the Elekit TU 8900. While driving the RP-600M IIs, the $125 Amp Camp amp came through as bass-crisp, midrange-detailed, and tactile, with only a moderate amount of dryness on recordings with dense reverb. Other than less-than-fully-recovered reverb density and the absence of that irreplaceable Venus-tube aura, the biggest differences between the ACA mini and the Elekit TU-8900 were in focus and the quantity of low-level sound exposed. Fortunately, these alterations were subtle; if you were not listening for them, you might never notice they were missing. With the free-as-can-be ACA mini powering the Klipsches, the sound was ridiculously full-flavored and satisfying. It felt like an amp-speaker combo for the ages.

In my view, Klipsch's RP-600M II is already a classic. I see it as today's version of my 1993 Acoustic Research M1 or maybe the Spica TC-50 that was popular in the mid-1980s. In my system, it sounded exactly as romantic or resolving, as thrilling or dull, as the amp I chose to drive it with.— Herb Reichert

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Footnote 1: My B-weighted estimate of the original RP-600M's sensitivity was considerably lower, at 89.6dB(B)/2.83V/m, though this is still higher than is typical for a small two-way speaker, especially considering its higher-than-average impedance.—John Atkinson

Footnote 2: See diyaudiostore.com.