Recording - August 2018 - 30

ART RM5
Active Studio
Monitor
An unusual design yields

significant sonic dividends
REVIEW BY MIKE METLAY

RT has been around for a good long while,
but it's not a company known for its monitors
(that tended to be the province of sister
company Yorkville Sound). With the RM5, though,
that's about to change. We found this remarkable
new monitor system to be truly attention-getting, in
all the right ways.

Not your average box

The RM5 is a stereo monitor system intended for reference
monitoring as well as casual hi-fi and home theater listening.
It's designed to fit in relatively small spaces while producing
high yet clear listening levels. That's all well and good; it's the
remit for pretty much any small speaker we review. How the
RM5 accomplishes this task, however, is unusual.
The key to the sound of the RM5, particularly on the low
end, is its construction. Each speaker is a heavy, rigid aluminum
unibody design, 12.4 x 7.6 x 3.6 inches in size. That's not a
typo-these speakers, which are full-size 2-way designs with
5" woofers, are less than four inches thick. Looking at them
straight on, they seem no different than any other small-format
monitor, but from the side they look like someone's shaved off
the front of the box and set it up on its own. As a result, they'll
fit in places many speakers won't, including flush against
walls-they come with removable custom stands and VESA
mount points for permanent placement on walls.
How does the RM5 get away with having such a small
internal volume? The secret is in its dual passive radiators.
The aluminum unibody shell of each speaker makes up its
front, back, top and bottom; the two sides are flexible
passive radiators, rectangular in shape rather than the traditional
round design. They're designed to vibrate in sympathy with
the woofer and with one another, to extend the low-end
response of the monitor.
Sealed cabinets with passive radiators represent an alternative
to cabinets with tuned bass ports. Note that neither design
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RECORDING August 2018

is "better" or "worse" per se; good engineering and careful
design can yield world-class results in either case. Most of the
speakers we review are ported, but we're seeing more and
more sealed cabinets with passive radiators as time goes on.
The drivers themselves are a 5" composite woofer and a
ring-radiator tweeter with a center plug and waveguide
surround for a very wide sweet spot. Amplification is 125W
per woofer and 25W per tweeter for a total of 300W, and
the crossover frequency is set at 2.2 kHz. Maximum SPL at
one meter is 109 dB, and the rated frequency response (±3 dB)
is 45 Hz to 22 kHz (the Nyquist frequency for the internal DSP).

The innards

The RM5 is shipped as an active/passive stereo system,
with all amplification and electronics contained in the Right
speaker. A 4-pin locking cable feeds the Left speaker's drivers,
and all other connections and controls are on the Right side.
There's nothing stopping you from reversing the speaker
positions if that's more convenient; you'll just have to swap the
inputs-and remember that you did it!
The RM5 is a completely digital speaker, with internal DSP
and 24-bit/44.1 kHz conversion on input. All connections are
on the bottom of the speaker, which is held up by a bolton metal stand. There's a pair of XLR/TRS combination jacks
for balanced or unbalanced analog signals, a minijack Aux
input, and built-in Bluetooth for wireless playback from smartphones or other mobile gear. A 2-prong power cable completes
the wiring complement. A small 3-way slide toggle lets you
select 1/4 Space, 1/2 Space, or Full Space placement, to
compensate for wall or wall/corner mounting. I'd strongly

Table of Contents for the Digital Edition of Recording - August 2018