Up here in the rarefied air of S&V World Headquarters — as we plot world domination, drink our lattés, and await the next $10,000 or $20,000 suite of loudspeakers submitted for our approval (or otherwise) — it can be all too easy to forget what most Americans actually consider to be "a whole lot of money." For example, 1,800 samolians: the amount that Polk demands for the RTi A Series speakers under review here.
The Polks' basic appearance is simple but attractive, with nothing cheap-looking about their smoothly curving real-wood finishes (vinyl for the subwoofer) or knit grilles. The RTi A3 bookshelf speakers and the CSi A4 center channel are straightforward two-ways. Ditto the FXi A4 surrounds, which add a second tweeter to qualify — barely — for dipole/bipole status. The DSW Pro Series 500 sub is fairly large for a 10-incher, rather heavy, and surprisingly full-featured, given its modest price.
I placed the Polk RTi A3 front speakers on adjustable stands flanking my 52–inch Samsung TV, the CSi A4 center on a low stand at its bottom edge, and the FXi A4 surrounds on high shelves astride the listening position. The DSW Pro 500 went in my layout’s customary subwoofer location, to the left and behind the front left speaker, with my preamp/processor’s sub output connected to its unfiltered LFE input.
All of the Polk satellites include wall-hanging facilities, and the dual-ported A3’s rear vents incorporate a nifty wall-standoff/turbulence-reducer that Polk calls a PowerPort. But I can’t recommend wall-mounting for the front trio of speakers: When I listened to them with my stands set right against the wall, the sound was excessively warm and bass-heavy — precisely what you’d expect from a midsized two-way so located. Moving the A3 pair (and the CSi A4) roughly 3 feet out from the wall made a dramatic improvement.
Thus placed, the A3 speakers now delivered full-range stereo music with impressively uncolored mids on both male and female vocals. The sound was still just on the warm side, but treble was ample and generally well balanced, and the midbass rich but not boomy. Polk's RTi A Series employs a fancy laminated cabinet material — six layers, each with damping material in between — and extensive internal bracing, which may contribute to the excellent midrange clarity and balance I heard. (It may also explain why, when given a sharp knuckle-rap, the cabinet yields a substantial "thock!" but doesn't emit the ringing that's typical of a cheap, thin-walled enclosure.
Whatever the case, the A3 pair's smoothness on vocals, brass, strings — pretty much everything — was very satisfying. They also produced surprising bottom end. For example, the standup bass on the title track of Norah Jones's Come Away with Me was well represented down to 40 Hz, and if it wasn't the tightest or "quickest" bass I've ever heard, it was by no means flabby or poorly controlled. Considering that the A3 costs $460 a pair, you can color me impressed.
I did find the A3s to be fairly finicky as to vertical placement. The sweet spot proved to be a bit below the center of the woofer cone, so I adjusted my stands up to 31 inches. Combined with toeing the speakers in a good bit, this placement delivered the smoothest, most open response — and it made a substantial improvement in upper-treble ease and airiness, which could be heard on things like ride cymbals and orchestral recordings' hall sound. (On the minus side, this setup also makes for a fairly compact ideal listening area.) Aside from a faint touch of peakiness in the high-treble octaves, and a vestigial remainder of midbass warmth, the Polks' tonal balance was pretty danged close to perfect.
For multichannel listening, the CSi A4 center made a solid match to its mates. Tonality was well balanced with the RTi A3 pair, and while the center speaker was slightly less warm and a bit crisper on both male and female voices, the shift was smaller than what I've heard from many other centers at this price range and higher. Lateral spread was good but not great. The CSi A4 maintained adequate balance of low-to-treble sounds over about a 45° arc, but moving much beyond that point — imagine sitting on the arm of a full-sized sofa placed 8 to 10 feet from a typical 42- to 50-inch screen — resulted in a modest loss of attack and articulation on voices and instruments.
All together, however, these crabbings pale in the glow of the Polk system's honest-to-goodness big-screen sound. I Am Legend may be a fairly standard-issue zombie flick (unless you share your life with a German Shepherd — I had to skip one particular scene!), but the Blu-ray Disc's Dolby TrueHD soundtrack is knockout stuff. The Polks laid it all out with surprising power and clarity, not once displaying a sonic wart that would divert attention from the screen.
While Polk's FXi A4 indeed sports a "dipole/bipole" switch on its rear terminal panel, its single-woofer/dual-tweeter design means the dipole (and bipole) action is necessarily limited to the tweeters' operating band, and so falls short of the deeper and wider midrange on-axis null of fully symmetrical, four-driver dipoles. Nevertheless, in their dipole setting, the Polk surrounds proved eminently capable on big-action soundtracks. For example, in the deer-chase scene early in I Am Legend, the zooming, roaring, and screeching of Will Smith's Mustang dominated the aural landscape, echoing impressively through the empty canyons of midtown Manhattan. And the sound effect of clattering hooves managed to track the fast-moving deer without sharply hot-spotting one or another speaker.
The DSW Pro 500 subwoofer proved very well matched to the rest of the system. Under direct comparison to my everyday single-12 (some four times its price), it did surprisingly well on familiar bass-off material, like the fire scene in chapter 6 of The Incredibles. The Pro 500's sound remained clean, deep, and boom-free to quite high levels — close, in fact, to reference level in my setup, which is several dB louder than my normal listening volume. In short, the Polk sub provided an ample bass foundation down to 30 Hz or so, with plenty of output for this comparatively modest layout. Yes, my bigger, far more expensive sub would play 6 dB louder before sending out audible distress calls, and it sounded more seismic and a touch tighter even at lower levels. But let's be reasonable: For just south of $600, the DSW Pro 500 rocked.
This is also an unusually full-featured subwoofer for the price. It's a down-firing sub, but you can change over to smaller screw-on feet on the control panel for front-firing use, as when installed in a cabinet (something I'd discourage for any sub). It also includes a mini-remote that lets you adjust sub volume, shift phase by 90° jumps, and select among (but not bypass) four fixed equalization curves. None is named Flat — but the third, Mid-Wall, sounded the most balanced in my setup, which actually does use a more or less mid-wall sub location. There's also a remote-selectable Night mode that simply cuts level by half (-10 dB).
An old family friend — for decades the chief blender for a very large, very familiar, and very British tea brand — once told me that any fool could blend excellent tea from only the most expensive leaves; the true art was in achieving equal success while using 95% cheap stuff. As it is with tea, so it is with speakers. This Polk RTi A Series system proves that you can indeed assemble a 5.1-channel layout with honest tonality, cinema-style spatiality, and impressive dynamics, for a good chunk less than $2,000. I suspect this will be very good news to lots of folks, especially the hordes of upgraders who just went $500 or more over budget on that spanking new HDTV.
Key to Above Graph:
• L/R 80 Hz to 16.7 kHz ±4.0 dB
• Center 83 Hz to 17.2 kHz ±3.8 dB
• Surround 88 Hz to 16.3 kHz ±2.9 dB
• Subwoofer 40 Hz to 105 Hz ±2.0 dB
Frequency response (at 2 meters)
front left/right: 80 Hz to 16.7 kHz ±4.0 dB
center: 83 Hz to 17.2 kHz ±3.8 dB
surround (bipole): 87 Hz to 16.5 kHz ±3.9 dB
surround (dipole): 88 Hz to 16.3 kHz ±2.9 dB
subwoofer (Corner mode): 40 Hz to 105 Hz ±2.0 dB
Sensitivity (SPL at 1 meter with 2.8 volts of pink-noise input)
front left/right: 89 dB
center: 89 dB
surround (bipole): 88 dB
surround (dipole): 87 dB
Impedance (minimum/nominal)
front left/right: 4.0 / 6 ohms
center: 4.1 / 5 ohms
surround: 3.1 / 4 ohms
Bass limits (lowest frequency and maximum SPL with limit of 10% distortion at 2 meters in a large room)
front left/right: 80 Hz at 86 dB
center: 80 Hz at 88 dB
surround (bipole): 80 Hz at 86 dB
surround (dipole): 80 Hz at 84 dB
subwoofer: 25 Hz at 81 dB SPL
99 dB average SPL from 25 to 62 Hz
107 dB maximum SPL at 62 Hz
bandwidth uniformity: 93%
All the curves in the frequency-response graph are weighted to reflect how sound arrives at a listener's ears with normal speaker placement. The curve for the front left/right channels reflects response of the RTi A3 averaged over a ±30° window. The center-channel curve reflects response of the CSi A4 averaged over ±45°, with double weight directly on-axis of the primary listener. The surround-channel curve shows the response of the FXi A4 averaged over ±60°.
All satellite speakers were measured on a 6-foot stand, which gives anechoic results to approximately 200 Hz. All upper-channel measurements were taken at a full 2 meters, which emulates a typical listening distance, allows larger speakers to fully integrate acoustically, and (unlike near-field measurements) fully includes front-panel reflections and cabinet diffraction.
L/R, Center, and Surrounds
Polk Audio's RTi A3 displayed a 2-dB rise from 700 to 1,100 Hz and considerable peakiness above 3 kHz, but its directivity was tightly controlled. The CSi A4 center channel has fairly severe off-axis lobing at listening angles greater than ±22°. The FXi A4 surround's average response looks similar to that of the CSi A4, but its trace doesn't fully show the differences in response when measured at various radiating angles. For example, when measured directly on axis in bipole mode, response was +5 dB between 1.5 and 3 kHz with up to 15 dB less output above 8 kHz as compared to the dipole mode (shown in graph).
Subwoofer
The DSW Pro 500 subwoofer's bass limits were measured with the sub set to maximum bandwidth and placed in the optimal corner of a 7,500-cubic-foot room. In a smaller room, users can expect 2- to 3-Hz deeper extension and up to 3-dB higher sound-pressure level (SPL). Basic measurements were taken with the subwoofer in the Corner operating mode, but the EQ changes in the other modes are easily described in the text.
Measurements of the DSW Pro 500 subwoofer reveal a moderate dynamic capability. The Cabinet mode increases response below 60 Hz by 3 dB, while Mid-Wall increases output by roughly 1.6 dB over the same operating range. The Mid-Room mode raises output below 100 Hz by 1.5 dB, with a gradual increase to +7 dB by 25 Hz. The actual response of the sub's crossover runs from 60 to 105 Hz (the specifications state 60 to 120 Hz), and there is only a small volume/crossover interaction.