PRODUCT REVIEW
studios reside in homes or areas that require
sensitivity to volume, what are we to do?
RIVERA
Silent Sister
Isolation Cabinet
BY STEVE OUIMETTE
In the beginning, amps started out as low-wattage affairs with just enough power to
project the guitar in a relatively small venue.
Soon, the need for more power gave us amps
that pushed hundreds of watts. When that
wasn’t enough, amps were daisy-chained in
order to be heard in arenas. When PA systems became more efficient, it was possible
to amplify music with a lot less power on the
guitar amp side. However, recording studio
owners desired lower volume amps, which
resulted in the design of the master volume.
The logical progression of the master volume
lead to attenuators, and later power scaling,
and then full circle right back to low-wattage
amps. Many guitarists have continued the love
affair with big, loud amps, yet are having a
hard time finding places that will let us wind
up our beloved rigs to record them in all their
glory, especially at home! And now that many
a recipe for muffled tone. Lucky for us the
folks at Rivera have a solution.
One decidedly analog approach to reducing
volume in our increasingly digital world is the
use of an isolation cabinet. The concept is
simple: a speaker inside of a box that is sealed
up tight and treated acoustically to keep
the sound in, or at least to heavily attenuate
the signal. By design, iso cabs are made for
recording. People have been using iso cabs
for years with some success, but the main
issue that plagues the majority of iso cabs is a
boxy sound. The problem is, by trying to keep
sound from escaping the box you have to seal
it as tight as a drum, resulting in trapped air
that doesn’t let the speaker or the mic breathe
like they do in an open room. Top that off with
a metric ton of acoustic deadening material
and a very small enclosed space, and you have
Your sister is built!
Built of hardwood-core plywood and covered in black Nyflex carpet, the Silent Sister
is road-rugged and measures 16”x20”x30”.
Rivera added comfortable leather handles on
the top and sides of the cabinet, as well as
rollers that allow you to easily tote it around
like a suitcase on wheels. Inside is a Celestion
G12T- 75 8-ohm speaker that is pre-wired to
a jack panel on the backside of the cab for
easy connection to an amp. The two pre-wired
microphone goosenecks terminate on a panel
with two Neutrik XLR connectors. Access to
the goosenecks and speaker comes through
the top of the cab with a hinged door that
locks with a twist-lock latch. The top door
makes it easy to open and adjust the two mics
to whatever position you desire without having to get down on your knees to look inside.
What really separates the Silent Sister from
other iso cabs is a cleverly devised porting/
air labyrinth system that relieves the effects of
pressure build-up in a small enclosure while
reducing the external volume by about 30dB.
Additionally, the design makes use of specifically chosen angles to minimize standing
waves and reflections.
Can we get a little quiet, please?
This is the type of device that I’ve dreamed
about for years, hoping it would keep the cops
from busting down the door because some
neighbor didn’t appreciate my riffs. The first
test was to see what kind of reduction the
Silent Sister provided with my JCM800 100-
watt head. Because the speaker inside is a
75-watt, I used the very unscientific approach
of not turning the amp up all the way, just
to get a feel for the volume without blowing
the head or speaker. Setting the amp with
the gain on 10 and the master at about 3 you
could hear sound coming through the box
but it was significantly reduced in volume and
for the most part only produced a muffled
bassy sound at talking levels. Opening the
top lid showed how loud the amp was—night
and day with the lid closed. Just to be safe,
I engaged a THD Hotplate inline and shaved
4dB off the signal, then cranked the master
up to 10. At this point the outside volume was
