Bookshelf Speakers — Klipsch RP-600M II

The RP-600M II brings a second generation to the largest two-way stand-mount in Klipsch's Reference Premiere series. Klipsch is the American company founded by audio pioneer Paul W. Klipsch in 1946, known for the horn-loaded Klipschorn, and this model follows the same principle as its bigger designs - a horn-loaded tweeter combined with a light, stiff woofer for high efficiency. Compared with the original RP-600M, the II has a larger tweeter horn, a redesigned woofer and higher power handling. Unlike the smaller bookshelf models in the series, it can be bi-wired and bi-amped.

Key specs that matter

The RP-600M II uses a 1-inch titanium-diaphragm LTS (Linear Travel Suspension) tweeter in a vented housing, mounted in a 90 x 90-degree hybrid Tractrix horn. It works with a 6.5-inch spun-copper Cerametallic cone woofer, crossing over at 1.5kHz. Frequency response is 44Hz to 25kHz (+/-3dB), sensitivity is 94.5dB at 2.83V/1m and nominal impedance is 8 ohms. Power handling is 100W continuous and 400W peak. The braced MDF cabinet vents through a rear-firing Tractrix port, measures 40 x 20.2 x 33cm and weighs 8.2kg. Dual binding posts and a magnetic grille are standard, and the vinyl finishes are ebony or walnut.

Engineering and use context

Loading the tweeter with a horn raises its efficiency and controls its directivity, aiming the treble at the listening seats and reducing reflections from the walls, floor and ceiling. Tractrix is Klipsch's own horn profile, designed for efficient transfer of sound into the room, and the second-generation horn is bigger than before, which widens horizontal coverage. A compression-moulded silicone face damps horn resonances, while a computer-modelled phase plug smooths the tweeter's response and protects the diaphragm. The LTS suspension keeps the movement of the titanium dome linear to lower distortion, and the vented tweeter housing reduces standing waves behind the dome. The Cerametallic woofer cone is light and rigid and keeps its shape under drive. It is coupled to a dual-layer copper voice coil about 70% larger than in the first version, with an aluminium shorting ring in a redesigned motor to cut distortion, all held in a non-resonant stamped-steel basket. The rear Tractrix port is flared to move air with minimal turbulence and port noise.

Pairing

The high sensitivity and easy load allow high volume from small receivers and even from low-power valve amplifiers. The RP-600M II works as a stereo pair or as the front channels of a smaller home cinema, and its dual terminals make bi-amping possible.

Alternatives

Klipsch's RP-500M II is the smaller bookshelf model of the same series, with a 5.25-inch Cerametallic woofer.