Positioned as the entry-level of Polk's loudspeaker product line, the R/T/M Series utilizes many of Polk's advanced technologies within a variety of loudspeaker types, including bookshelf, floorstanding, and center. The R/T/M line consists of two floorstanding models (R300, M20), three bookshelf models (R150, T15, M10), and one center channel (CSR).

At $179.90 per pair, the Polk R150 makes a nice impression right out of the box. Fit and finish are solid, and the black vinyl creates a smooth, even appearance. The drivers look great, and the sturdy binding post panel and port fit great into the cabinet. The R150 employs a ¾-inch Dynamic Balance silk/polymer composite tweeter with a neodymium magnet coupled to a 5 ¼-inch Dynamic Balance mineral filled polymer composite cone woofer with a butyl rubber surround, both utilizing acoustically inert stamped driver baskets. It employs a rear-firing bass port, on the left bottom corner, and anti-diffraction grills that have a nice taper at the bottom. Developed in conjunction with Johns Hopkins University, Polk's exclusive Dynamic Balance technology resulted from a laser interferometry research project that enables Polk to analyze the entire surface of a vibrating driver in real time, in order to determine the right combination of materials for the particular product.

Sound
The R150 presents a nominal 8 ohm load with an 89dB efficiency. The speaker performed very well with even entry-level receivers, but, of course, things did improve with better quality power. I listened to the R150s with music sources, mounted on stands in a stereo setup. The R150, incidentally, offers no on-board mounting hardware (unlike its siblings the T15 and M10). The R150 presented a surprisingly deep, wide soundstage with above average imaging and good quality dynamics. Tonally, the R150 had detail but also some shrill to the high frequencies; however it offered a smooth blend into its midrange and upper bass. The midrange had a good level of clarity and smoothness, but overall had some muddiness. Its low bass lacked overall punch and depth, but still had a pleasing overall character. I thought the R150's overall coherence suffered a bit because of these specific anomalies, which didn't quite disappear into the whole. Its lightweight bass and slightly brittle top end did stick out a bit, and the midrange, while good, didn't captivate and grab my attention even on midrange-dominated material. The R150's sound, of course, varied with the material. The R150 tended to favor warmer recordings with less bass content. Rock and electronic music sounded good, but some tracks had a bit of a fatiguing quality. Overall, the R150 provides good sonic performance, but nothing exemplary at its price point.

High Points
• The R150 provides a good level of sonic performance at its price, along with very tight fit and finish.
• The R150's light weight and small size allow for easy bookshelf placement.
• The R150 looks terrific with or without the grills.

Low Points
• The R150's treble has some harshness, the midrange some muddiness, and the bass lacks overall depth.
• The R150 throws a deep, wide soundstage, but the image can be a little fuzzy at times.
• The R150 lacks on-board mounting capability.

Conclusion
The Polk R150 doesn't distinguish itself sonically amongst other loudspeakers in its class. Its overall coherence and listenability suffered due to its inconsistencies across all of the frequency ranges. However, its fit and finish and overall cosmetic profile compete very well in the category; although its lack of on-board mounting hardware did stick out a bit. At the price, it's hard to go wrong with these speakers.