Sound & Vision (2019-04)

Sweet, clean highs

Superb dialogue clarity

Detailed but not

aggressive sound

Slightly limited treble

diffusion

R3s make for pricey

surrounds

Price: $10,200 (as tested)

GP Acoustics (US) Inc.

732-683-2356

us.kef.com

At a Glance

midrange cone, to reduce
distortion. Internal bracing in
the cabinets has been further
stiffened. Also, the trim around
the drivers, which KEF calls
a Shadow Flare, has been
sculpted to minimize cabinet-
edge diffraction. The paper-
based cones of the bass drivers
are now skinned in aluminum to
provide higher excursion, and
new, flexible ports are said by
KEF to reduce resonances.

THE LINEUP

The R Series system I received
for review consisted of the R5
floorstanding towers ($2,800/
pair), a set of standmounted R3s
($2,000/pair) for surrounds, the
R2c center speaker ($1,200),
and a quartet of small, wedge-
shaped R8a speakers ($1,400/
pair) for Dolby Atmos duty.
The R8a has spaced slots in
the rear for a side-wall setup,
but is mainly intended to
provide upward-firing, ceiling-
reflected Atmos sound. Each
R Series model apart from the
R8a employs a 5-inch Uni-Q
midrange-treble coincident
driver together with one or
more separate woofers, making
them true 3-way designs. (The
two-way R8a features a 5.25”
Uni-Q driver.)
The R Series comes in
striking gloss black, gloss
white, and walnut finishes, with
the drivers tinted to match. The
magnetically-aached grilles
have a very thin frame and
are covered with perforated
microfiber cloth. I found the
grilles to have a marginal effect
on the treble, so I opted not to
use them.
The dual pair of speaker
terminals on the R5s and R3s
can be connected internally by
turning a knob on the terminal
plate if single-wiring is used (as
it was here). Unlike the usual
external metal straps, the link
is invisible, so make sure to
un-turn and disconnect them if
you’re aempting a bi-wire or, in
particular, a bi-amp setup. KEF
also provides adjustable foam
bungs to fully or partially block
the two rear bass ports.

position, and toed-in toward

the center seat. The center

speaker was placed on a low

stand, while the four R8a Atmos

speakers sat atop the front R5s

and rear R3 surrounds.

My review system included

Marantz UD7007 and Oppo

UDP-203 disc players, a

Marantz AV8805 preamp-

processor, and a Parasound

Halo A 52+ five-channel ampli-

fier. Two channels of an Outlaw

750 amp were tapped for the

surrounds, while a seven-

channel Outlaw 7220 amp

was used to drive the Atmos

channels.

IT’S ALL ABOUT

DA BASS

For this review, I used both

Kube12b subwoofers to get

the results reported for movies

and music. I had anticipated

the contribution of the Kube12b

subs when I chose the R5s—the

smallest tower speakers in the

new R Series. Why pay for the

extra bass offered by the larger

R Series towers when you’ll be

rolling them off at around 80

Hz? Listened to without the

subs, the bass put out by the

R5s was impressively tight and

detailed and might well shine in

a small room. In mine, however,

the R5’s bass was simply too

lightweight.

Aer some initial trials, I

ended up stacking the two

KEF Kube12b subs together

against the room’s le side wall.

This improved performance by

combining output capability but

sacrificed any benefit that sepa-

rately located subs would offer

for multiple seating positions.

A frequent issue in my

room, one that varies with the

speakers being used, is a rise

in response centered around

150 Hz. This was audible with

the KEFs, thickening the sound

and muddying inner detail. To

correct the problem, I at first

tried equalization but eventually

decided against it and instead

inserted the optional port plugs

on the speakers and reduced

the bass control on the Marantz

pre-pro. Together, these tweaks

greatly reduced the upper bass

bump I had been hearing. I then

adjusted the subwoofer level

to beer match up the upper

and lower bass. While a 110 Hz

crossover seing measured

best (I used the Omnimic

measuring system from Parts

Express to confirm my results),

an 80Hz seing sounded beer,

so that’s what I went with. I also

used a +1dB treble seing on

the Marantz, which added a bit

more top-end air to the sound.

MUSIC PERFORMANCE

When listening to the biggest

Kodo-style Taiko drums to

The R5s come with outrig-

gers for enhanced stability.

Spikes are provided, though I

didn’t use them.

For a subwoofer I chose

KEF’s Kube12b ($700), a model

that previously appeared in

our June 2018 review of the

company’s Q350 speaker

system (available online at

soundandvision.com.) The

Kube12b is a relatively compact

design providing basic features

such as level, two-position

phase, line- and speaker-level

inputs, low-pass crossover,

and three fixed EQ seings, but

no programmable room EQ or

wireless connection options. I

requested two of them to help

fill my large listening space, and

even the pair turned out to be

just barely enough.

The KEF R-series (and the

Kube12b sub) is designed in the

U.K. and manufactured in China.

SETUP

My home has a bass-chal-

lenging, open-concept floor

plan that more than triples the

16 x 21-foot section carved out

for my home theater setup. The

non-flat ceiling height is an esti-

mated average of 9 feet. I set up

the R5s on the 16-foot dimen-

sion, about 3.5-feet out from

the closest walls, roughly 9 feet

apart, 11 feet from the listening

soundandvision.com (^) [ 53