PSB Stratus Speaker System

Home Theatre Surround Sound

By Les Enser

PSB speakers have been with us for just about twenty years now and company founder and engineer Paul Barton continues his relentless effort to reach for the stratosphere.

Barton consistently strives for sound quality and reliability and his latest line, conveniently named the "Stratus series", is another example of what he is trying to achieve.

The toughest part of this setup was carrying and unpacking the hefty PSB Stratus Silver main speakers. Packaging was first rate, as the speaker is well protected from the dangers of everyday shipping, ensuring greater chance of the speakers arriving to your door in one piece. Out of the box the speakers certainly look handsome. My demo pair had a black piano gloss finish with beveled corners and nicely integrated speaker grills.

The Stratus’ side panels are made of a wood composite that is 40 percent heavier than the wood in most other speakers. No wonder my back was complaining when lifting these babies!

The sides are joined with a tongue-in-groove aluminum extrusion. Rapping the cabinet with my knuckles produced no ringing whatsoever. This convinced me that whatever sound we would hear would come from the speakers and not the cabinet. Even though the speakers are tall (38.75"), the cabinet is so slim that less than one square foot of floor space is occupied!

The speakers are of a tower design sporting two 6.5" woofers with a one inch aluminum dome tweeter mounted between them. Although using a three speaker configuration, the Silvers are a two way design that incorporates the famous "Linkwitz-Riley" crossover - at 24dB-per-octave. This is said to provide a smooth transition from the woofer to the tweeter in both amplitude and phase, a necessary ingredient in the THX world.

The woofers each work at different frequencies. One works from 26Hz to 500Hz, while the other takes over from 500Hz to 2100Hz, which means the system seems to work in a quasi three way configuration.

Rated at 4 ohms, this speaker could put demands on entry to mid level receivers, since their power supply would have to produce the ample current that these speakers may demand at higher power levels.

The enclosure is of the vented type with a 2.5" port. Sensitivity, or efficiency, was measured at 91dB and power handling is rated at 200 watt. Frequency response is 26Hz to 24 kHz.

The matching Stratus center channel also had a gloss black finish with two 4.5" woofers in a horizontal configuration with two "stacked" tweeters in between. The tweeters are set up this way to minimize the "lobing" that can cause an unstable effect in the center channel. The idea is to keep voices and effects anchored to the television screen the way a center channel should.

Cabinet dimensions are 19 ½"w x10"d x 7"h.... not a bad size for most televisions or big screens. I placed the unit on top of my Sony XBR just slightly above ear level and was quite satisfied with its sound.

As for the rear speakers, PSB provided the Ambient II, a dipoler design with two 51/4" woofers and two ½" tweeters. Dimensions were 11" h x 11"w x 8" deep. The dipoler design, which emanates sound by using two sets of drivers working in opposition, is said to create a diffuse field without drawing attention to themselves.

Fortunately, PSB included the mounting brackets. I mounted the speakers about 7’ high on the walls with the "null side" facing in laterally to the listening area. Unfortunately, the matching subwoofer did not arrive on time, so I tested the system without one.

Now for the fun.

I toed in the main speakers about 10 degrees for the best sound coverage and fired up my trusty old Laser Disc player for the true test. I used the latest release from Al Pacino and Robert DeNiro ("Heat") for my first sample.

Dialogue was crisp and clean and I did not have to strain to hear Pacino’s smoky voice. The stacked tweeters certainly helped out here. The robbery chase scene was truly mesmerizing. The panning effect of the getaway car from left, center, right channels was bang on. There was no evidence of mismatch of timbre, the center channel worked perfectly with the mains. Gunshots had depth and attack, while the screeching of tires made one’s heart pound as if one were actually driving the car. An excellent scene for an Adrenaline rush!

The PSBs kept me involved in the action. The final scene of Heat, where DeNiro and Pacino match wits, takes place on a busy airstrip. The roaring of jet engines sounded as if my livingroom had become a runway!

The depth and cleanliness of the speakers was truly impressive, and the soundfield was seamless. Even though a subwoofer would have enhanced the low frequency effects, it was not sorely missed; the Stratus Silver mains did very well on their own!

In the famous T. Rex scene from Jurassic Park the Silvers again held their own, suggesting that a subwoofer is not really necessary. Sound was clean, with no hint of duress or strain. The only time I ran into distortion was when my reference Onkyo receiver ran out of gas at higher than normal listening levels. PSB’s Ambient II rear speakers sounded totally unobtrusive, blending in and setting up a beefy surround soundfield. There was no hint of localized sounds from the rears, all in all a perfect match to the rest of the speaker system.

As for true stereo listening, the Silvers showed good bass response with a well balanced high end, though the midrange did tend to sound somewhat confined, or "boxy." In terms of imaging they did an admirable job, but I felt they could do better. I blame my listening room for that, though, since the ceiling is so high (14ft.) and the room is so small I was forced to have the speakers too close to the listener (8ft away). Still, these speakers are worth looking into.

If you’re looking for a speaker system that is perfectly matched for home theater, look no further. They are handsomely designed, have good bass output, don’t take up a whole lot of room and are a decently priced. What more could anyone ask for?

(price as tested, in Canadian dollars)

PSB Stratus Silver...Price as tested $1499/pr.
PSB SC5 Center... Price as tested $499.
PSB Ambient II... Price as tested $449/pr.

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