Polk Audio RTi A1
Every now and then, while performing
research on a piece of review equipment, I stumble on interesting bits of information that
make me sit back and think, "Huh. How bout that!" A case in point: I was
surprised to learn of the origins of Polk Audio, and how the company has come to be a
keystone brand of home-audio equipment.
In 1971, university buddies Matthew Polk, George Klopfer,
and Sandy Gross were asked to produce a sound system for a bluegrass convention in
Baltimore, Maryland. Polk, being a physicist, said hed design the system if Klopfer,
then a cabinetmaker, would build the enclosures. Hands were shaken and a sound system
built. But following the convention, the three were told that the producers couldnt
afford to pay for it. Klopfer designed a logo and attached it to the speakers, Gross took
on the role of marketing, and, in 1972, Polk Audio was born.
Concentrating for a while on professional sound equipment,
Polk Audio later focused its attention on high-end audio gear for the home. After the
success in 1974 of their first model, the Monitor 7, Polk began to earn an excellent
reputation in audiophile communities, and in 1999 the company went public. Today, Polk
Audio offers a vast array of audio products, ranging from stereo and home-theater speaker
systems to car and marine equipment. In the middle of their home-audio speaker range is
the RTi series, which comprises three floorstander, two center-channel, and two
bookshelf models. It is the smaller bookshelf speaker that I review here: the RTi
A1 ($339.95 USD per pair).
Technically . . .
. . . the RTi A1 is a magnetically shielded,
dual-ported, two-way bookshelf speaker with a 1" silk/polymer-composite dome tweeter,
a 5.25" polymer/mineral-composite mid/woofer, and two ports: one each on the front
and rear panels. Housing all of this is one of the most impressive cabinets Ive seen
on a stand-mount offered at this price or even quite a bit north of it. To my knowledge,
Polk Audio is currently the only manufacturer offering real-wood veneers (Natural Cherry
or Black Oak) on a $340/pair minimonitor -- the RTi A1s look is one of
luxuriously high quality. Looking under the impressive skin of this cabinet, I discovered
that its built using Polks Damped Asymmetric Hex Laminate Isolation (DAHLI)
design technology, which is used throughout the entire RTi line. DAHLI --
basically, six layers of MDF separated by five layers of viscous damping material -- is
said to create optimal sheer damping (OSD) to help eliminate cabinet colorations. In
addition, the RTi A1s cabinet is internally braced, and has tapered side
panels to further reduce internal resonances.
The front port, just below the mid/woofer, uses a
technology Polk calls Acoustic Resonance Control, which takes advantage of the
cabinets internal resonance created by the back wave of the driver. Polk matches in
frequency this form of cabinet resonance with the front ports tuning frequency.
Since the ports and the cabinets internal resonances are out of phase, peak
resonances within the cabinet are canceled, resulting, its claimed, in a more
natural sound with reduced midrange distortion.
The rear port, behind the tweeter, uses what Polk calls
their PowerPort technology. Essentially, its a long, flared port with a dispersing
cone mounted just past its end. This reduces turbulence in the air exiting the cone,
thereby diminishing port noise, or "chuffing," while providing deeper, cleaner,
more authoritative bass.
In designing the mid/woofer and tweeter, Polk used a
process called Dynamic Balancing, in which a laser is used to study the components of the
speaker at a microscopic level, in order to reduce or eliminate behaviors or artifacts
that color the sound. Finally, another process, Klippel Optimization, was employed to
ensure that the RTi A1 offered balanced yet dynamic sound at both low and high
All of these technologies came together to help this little
bookshelf -- it measures only 12"H x 7.38"W x 11.5"D -- reach as low as
60Hz, -3dB, while maintaining an efficiency rating of 89dB. Such performance somewhat
belies this minimonitors small size and affordable price.
I set up the Polk RTi A1s in my 13 x 25
listening room on a pair of 24"-high stands, each positioned 1 from the front
and side walls. Power was provided by an Arcam A18 integrated amplifier delivering 50Wpc
through River Cable Starflex speaker cables, and all recordings were played through a
Denon DVD-5910CI universal player connected via River Cable Audioflex Gold Plus analog
interconnects. I toed-in the RTi A1s so that their tweeter axes crossed about
1 in front of my listening position, which allowed me to lean forward and compare
their sound on- and off-axis.
When I listened to "Train Wreck," from Sarah
McLachlans Afterglow (CD, Network 30322 2), the bass was well controlled and
rhythmic, and managed to do a surprisingly believable job of anchoring the soundstage. I
was surprised because I had to keep reminding myself that there were only two 5.25"
mid/woofers were providing all the bottom end I was hearing. Had I been less familiar with
the speakers and had someone told me that there was a 6.5" woofer behind each grille,
I might just have bought it.
Voices were slightly more forward than Im used to
hearing from my B&W DM601 S3s, and were delivered in a full, coherent manner that
placed McLachlan at dead center stage. Changes in vocal texture and volume were clearly
perceivable in softer passages, showcasing the RTi A1s terrific microdynamic
abilities. At higher levels, the Polk sounded remarkably uncolored and detailed, and
showed no sign of stress. In fact, one of the little Polks greatest virtues was its
ability to paint the same sonic picture equally well at volumes low and high. Anyone
living in an apartment or condo will appreciate a speaker that doesnt lose midrange
subtlety when played at lower volumes.
I then moved on to B.B. King & Friends: 80 (CD,
Universal 6 02498 84246 1). "The Thrill Is Gone" was a logical choice to
audition next with the volume level left high -- who listens to the blues quietly? The RTi
A1s delivered a wide, holographic soundstage that was remarkably three-dimensional on
axis, and only slightly less so off axis. Instruments and voices were delivered with
fantastic realism and space, each clearly occupying its own place on the stage. I was
impressed by how easy it was to distinguish the different layers of the music, and how
well they corresponded with the depth of the soundstage. Had I been given a
birds-eye view of the stage, I could quite easily have mapped out where each
instrument (and B.B.) was positioned.
However, the electric guitar on this track sometimes
sounded a bit too sharp in pitch. This tended to worsen as the volume increased, but it
was subtly tamed by replacing the grilles. This could be due, in part, to the fact that
the grilles used on all RTi speakers were designed to reduce diffraction in an
effort to provide a more natural sound.
In "The Night We Called It a Day," from Diana
Kralls The Look of Love (DVD-A, Universal 6 02498 61248 4), the
singers voice was marvelously focused and positioned at high center stage. Piano
notes were wonderfully articulated and filled the air, with a terrific tonal balance not
typically heard through a minimonitor in this price class. That the RTi A1 was
handling transients well was evident in the snappy sound of the cymbals and the level of
detail audible in the sound of brushes slid over the snare-drum head. This speaker was no
stranger to the resolution of fine details, especially when fed a hi-rez signal. But with
this track the showstopper was, again, the bass response. Im not sure how Polk has
done it -- perhaps a slight increase in midbass output, or all the technology poured into
the exemplary cabinet design -- but the bass sounded as if produced by a much bigger
bookshelf speaker, or even a small tower model. I got up to recheck the speakers
placements, just in case Id accidentally moved them slightly in setup and thus
stumbled on a hitherto unknown sweet spot in my room. Unfortunately, I hadnt;
fortunately for the rest of the world, the RTi A1 was that good.
Finally, I moved on to an old favorite, Pink Floyds Dark
Side of the Moon (SACD/CD, Capitol 82136 2), and listened to "Us and Them."
Once again, the highs were detailed and extended, with realistic amounts of space between
instruments and voices. Nor did the "air" evident in the subtler passages
disappear during the intense choruses, the result being a clear, dynamic presentation of a
track that can sometimes sound rather congested through lesser minimonitors. While the
bass line wasnt quite as compelling as with other recordings, I didnt find it
lacking much -- the low frequencies were rolled off in just the right place, to imply what
was missing. From so small a monitor, what more can you ask?
While reviewing the RTi A1, I had on hand another
pair of similarly priced, albeit slightly older bookshelf speakers: the B&W DM601 S3
($450/pair, discontinued). The DM601 S3s larger (6.5") mid/woofer is housed in
a cabinet roughly 20% larger than the RTi A1s, but, as the Polks have
reminded me, size isnt everything. For most people shopping in this price category,
a speakers appearance will be nearly as important as its sound, and this is
something that Polk Audio has acknowledged. With its real-wood veneer, smoothly tapering
side panels, and modern-looking grille, the RTi A1 wins my vote in the looks
I began my listening to the B&W DM601 S3s at lower
listening levels, with Leahys eponymously titled album (CD, Virgin 564147).
The first thing I noticed in "The Call to Dance" was the B&Ws lack of
low-level detail. These speakers didnt seem to come alive until I gave them some
power. This could be in part due to the fact that, at 88dB, the DM601 S3 is slightly less
efficient than the Polk (89dB), but it would surprise me if this were the only reason. The
Polk, on the other hand, offered a nicely balanced sound regardless of volume level.
Turning up the gain to give the B&Ws the power they needed brought things to life,
albeit with a more relaxed sound. Leahys fiddle in "McBride" had a smooth,
fluid, texture through the B&Ws that was very easy to listen to, whereas it sounded a
little sharper and definitely more forward through the Polks -- similar to the electric
guitar Id heard earlier on the B.B. King disc. I wouldnt say that one was
better than the other; they were just different.
Listening to the title track of Katie Meluas Call
Off the Search (CD, Dramatico 0000266612), I was instantly struck by how coherent and
alive her voice sounded through the Polks. Here, the RTi A1s slightly forward
rendering of female voices made Meluas almost leap from the speakers, creating a
genuinely involving and dynamic sound. The image focus was tight and clean, especially of
the oboe, which seemed to float slightly above right center stage. The bass was smooth and
punchy, and reached just low enough to not leave me wanting more. The B&W DM601 S3
lacked the Polks focus and dynamics, but offered a little something extra in the
bottom end that prompted me to pump up the volume another notch or two.
Here things got really interesting: the B&Ws
began to sound midbass-heavy, almost boomy, and lost the smooth richness and control they
had at lower volumes. Pushing the Polks hard gave me none of the hassles the B&Ws did;
the RTi A1s kept their excellent composure while delivering very much the same
quality of sound -- just louder. I have no doubt that this is in part due to their
exemplary cabinet design, which allows the components within to do their jobs properly.
Since 1974, Polk Audio has earned a reputation for building
high-quality loudspeakers such as the RTi A1s, and for holding dear a few
fundamentals. First, they understand that a good speaker, be it stand-mount or tower, must
provide performance with two-channel music that is as compelling as it is with surround
sound. After all, most average consumers who purchase home audio equipment will have it
pulling just such double duty. Second, all of this performance and versatility must be
offered in an attractive package at an affordable price.
The Polk RTi A1 offers an impressively wide
soundstage filled with convincingly solid bass performance, tremendous dynamics,
well-focused voices, and a clean, detailed top end. If youre in the market for a
speaker package that offers you a huge bang for your buck, I highly recommend auditioning
. . . Aron Garrecht
|Polk Audio RTi A1 Loudspeakers
Price: $339.95 USD per pair.
Warranty: Five years parts and labor.
5601 Metro Drive
Baltimore, MD 21215
Phone: (800) 377-7655
Fax: (410) 764-5470