PROJECTOR
PICKER
Before you choose to go out
and buy any old projector that
fits within your budget, you
should first check that it’s
going to project an image that
matches the screen size you
want from its mounting—and
that the image will be bright
enough at that size.
The screen size projected is
a combination of the model’s
optics and the distance it is
away from the screen, this is
called the throw ratio. A ratio
of 1:1 means that, for every
foot away from the screen, it
would create an image one
foot across. Typically, home
theater projectors offer
default ratios around 1.2:1
backed up with optical zooms
of around 1.3x, so the final
image size can be adjusted.
Models with “short throws”
have a ratio of one or under
for use in smaller rooms or
placing on coffee tables, but a
newer trend is the Ultra-Short
Throw projector with ratios
of around 0.25. These can be
positioned directly in front of
the target screen and project
images of up to 100-inches
but, ideally, they work best
with specialized lenticular
screens. Projectors with
much higher throws of 2+ are
available for larger rooms
but are typically aimed at
conference venues.
A final attribute to consider
is brightness, measured in
lumens (nits come into this
too). Too low and the picture
will be a dim experience, too
bright and it compromises
the image quality and
increases noise levels of
fans keeping that bright
bulb cool. Typically, home
theater projectors range
from 2,000 to 3,000 lumens.
Conference projectors tend to
hit 5,000+ lumens. As a guide,
a 1,000-lumen projector with
a 100-inch screen would need
to run in a dark room for best
effect, a 2,000-lumen project
and 100-inch screen can cope
with medium ambient lighting.This latter part is interesting for home
theater use. AV amplifiers have always
been able to re-encode the input audio
from mono, stereo, or multi-channel to
best use its connected speakers. But the
move to Dolby Atmos has seen this change
from a fixed pre-rendered channel model
to a flexible ‘audio space’ with dynamic
audio objects that the input audio stream
is remapped to fill with the calibrated
speaker system. This enables you to
select a surround speakers configuration
that best fits your room size.
That could be a traditional 5.1 (five
surround speakers and a low-frequency
effect (LFE) subwoofer) arrangement for
smaller installations or a 7.1 arrangement
for larger ones with plenty of space for
rear speakers. You can add up- or down-
firing Atmos speakers for X.1.2/4 for
vertical audio. For seriously large rooms
with rows of seats, side speakers and
second LFE subs can be added for a 9.2.4
or even an 11.2.4 setup.
We could attempt to provide speaker
placement advice but the number of
permutations is large and, besides, Dolby
has come up with complete guides for
every single one: http://www.dolby.com/about/
support/guide/speaker-setup-guides/Thankfully these days, speaker
calibration is simplified. Even entry-level
AV amps offer automatic setup, using a
supplied mic placed at the viewer’s head
position and the amp will adjust the levels
and response time for each speaker.
All of this simplifies PC playback issues
as the video and audio can be sent over
your HDMI connection and you can leave
the amp to decode the audio, depending
on the bitstream it’s being sent, while
sending the video to your chosen display.
At worst, you might need to ensure the
correct audio device is driving the amp in
the Windows audio settings (remember,
it will be your GPU rather than mobo
onboard audio unless you’re using a
dedicated coaxial or optical link).IN THE STRUCTURE
The most nebulous section is the
infrastructure aspect, largely as every
home is going to be different. However, we
can point out the issues and requirements
that most installs are going to offer, even
if the actual layout will differ.
To begin with, get a floorplan of your
home, mark where the internet cable
enters your home, where devices that
require high-speed wired LAN will beSpeaker and sub placement are important for your
home theater, but so is good audio calibration.So... many... gold...
connections...
Theater AV amplifiers
are something to
behold, but all of
this is absolutely
necessary, honest!
MAR 2022MAXIMU MPC 53
© DOLBY