Review: Niles OS5.5 outdoor speaker

When we put together comparison tests, we often give manufacturers the parameters (i.e., outdoor speakers at $400/pair) and let them figure out what they want to send. For some reason, Niles chose to send the OS5.5, a speaker that costs just $259/pair. But after hearing the OS5.5, I have to wonder if that error was really an error at all, or if it reflects the company’s savvy about its own products.

The OS5.5’s 5-inch woofer uses a stiff, light carbon fiber cone — something found on high-end indoor speakers much more often than on outdoor speakers. The woofer basket (or frame) is actually molded into the enclosure, thus keeping the OS5.5 more compact than it would be if it used a separate metal woofer basket. The 1-inch tweeter is made from Teteron, a synthetic fabric. I tried to disassemble the speaker to check out the crossover, but the front baffle seemed to be glued as well as screwed into place.

At just 9.9 inches high, the OS5.5 is one of the smallest of the speakers in this group. It’s also the least expensive model we tested.


Given the OS5.5’s price and size, I expected its sound would be a notch or two down from that of the others, but it was Lauren’s favorite and one of my two favorites. Let’s hear from Lauren first: “I like it. The sound has more depth than the others. The mids and treble are clean and crisp, and the bass is strong and well defined. When I played ‘Thrift Shop’ by Macklemore and Ryan Lewis, this speaker was able to deliver the deep bass but also sounded clear enough so I could clearly hear the vinyl-record surface noise at the beginning. The only other one that could do that was Speaker 3 [the Klipsch AW-525].”

I characterized the OS5.5 as “a decent little speaker.” I noticed a fairly narrow, high-Q peak in the bass, something commonly found in small speakers intended for full-range use. This characteristic usually served the OS5.5 well; despite its small size, it seemed to have as much bass as the other speakers. It even played one of my toughest deep-bass tests, the first few notes of Holly Cole’s “Temptation,” without distorting.

I also noted a little bit of excess energy in the low treble, which gave vocals a more pronounced sound but sometimes added sibilance that I didn’t like. At the same time, it seemed to lack a little oomph in the lower mids. With all these ups and downs, the response sounded uneven, but still, I enjoyed the OS5.5.

Geoff didn’t. “The tonal balance wasn’t tilted toward bass or treble in particular, but it sounded like there were a lot of irregularities in the response,” he said. “It had the deepest bass of the bunch, though.”

The Verdict

So what have we got here? Generally good sound — at least for an outdoor speaker — with a compact design and a modest price. That all adds up to a confident endorsement for the OS5.5.

Test Bench

Frequency response of the OS5.5 measures 107 Hz to 20 kHz ±11.4 dB on-axis, ±8.9 dB avg 0°-30°. Measured impedance is 3.7? minimum, 8? average. Sensitivity from 300 Hz to 10 kHz averages 84.8 dB.