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Audio
Audio selectors, switches & controls
Three way input selector
Simple rotary switch routes any of the three pairs of
phono inputs to the phono output. Metal case with
gold plated sockets.
[BT31] £12.99
Volume Remote Control
Ever wished your amplifier had
remote control for the volume?
Now you can easily add IR remote
control to most amplifiers with
this simple device. It has two
phono sockets for line in and two
for line out. Simply connect it in
line, position the IR receiver
wherever you find convenient and
Selectors, Switchers, Controls & Convertors
4 Way audio control
A multi-purpose phono interconnect switcher which
can be used as an Input expander or comparator.
Connect up to four stereo devices (RCA phono) and
use a simple push button process for signal routing.
Eg pressing 1 & 4 connects input 1 to input 4.
pressing 1,2 & 4 connects all three. An internal
impedance matching circuit minimises audio losses.
Very handy.
[BT931] £19.99
4 channel stereo audio source selector
Allows 4 audio inputs to be fed into one.
Ideal if you wish to feed your VCR, DVD,
camcorder, satellite system, TV etc into
your hi-fi system which only has one
Aux/Line input. Features phono inputs
for simple connection and non slip
suction feet.
[SOURCESEL] £14.99
Digital audio – what’s what?
In the earlier days of digital audio the conversion from digital back into
analogue was always performed within the CD player itself. Now,
particularly with the advent of DVD, the thinking is to preserve the
signal in its digital form as long as possible to keep signal loss and
distortion to a minimum. This is achieved by routing the signal directly
from the player in its digital form into a suitably equipped amplifier or
TV for decoding and amplification. This process has led to a
bewildering array of terminology, a few of which we’ve attempted to
explain here:
S/PDIF, an abbreviation of ‘Sony/Philips Digital InterFace’, is a defined
standard for PCM stereo digital audio. It uses a single phono (RCA)
connector for electrical signals or a TOSLINK connector for optical
signals (the information contained in the signal is the same in either
case, and convertors are available to change one type into the other).
S/PDIF signals use different sampling frequencies for different
applications and can carry stereo audio (CD, minidisc or DAT) as well as
multi-channel surround sound.
AC3 (Adaptive Coding 3) is an audio compression standard based on
the S/PDIF PCM audio delivery system. Dolby Digital Surround AC3 is
a 6-channel surround sound system that uses the AC3 compression. The
sound is encoded to 5.1 channels (five full bandwidth signals plus a low
frequency channel for the subwoofer), and then encoded using the AC3
compression standard. AC3 systems are backwards compatible with
S/PDIF in that they will also decode stereo, but S/PDIF systems will not
necessarily decode AC3.
DTS, an abbreviation for ‘Digital Theatre Systems’, is another multichannel
digital audio standard which uses less compression than Dolby
Digital to give an arguably better sound. Some players and amplifiers
support both AC3 and DTS decoding although at time of writing there
is not much DTS encoded material available.
THX is not an audio standard in its own right, rather it is a very tight set
of specifications to which THX-certified equipment must be
manufactured. The brainchild of George ‘Star Wars’ Lucas, it was
intended to prevent the soundtrack of his films sounding different from
cinema to cinema because of equipment variations. In theory at least, the
film soundtrack should be faithfully reproduced in any THX-certified
cinema. THX in the home is generally an exercise in open-wallet surgery
as certified hardware is phenomenally expensive.
have easy volume adjustment.
Leds for power and confirmation
of ‘up’ and ‘down’ commands.
It can be used in a number of
ways:
• Inline in between pre/power
amp combinations
• Within tape line out/line in
loop (if vacant) with the amp
set to ‘tape monitor’
• In between say CD player line
out and amp line in (to control
that device volume only).
[VRC] £59.99
Sound mixing
Video sound mixing is the process of adding to or replacing the
soundtrack on your footage at the time that it is edited. Connections are
made as shown in the diagram. The norm is to have three channels on
the audio mixer; one channel being the incoming camcorder soundtrack,
another being a microphone input for commentary, and the other for
music from a tape deck, CD etc. The important thing about a mixer is
that all three channels can be present simultaneously, and so the final
result is not necessarily just
one channel or another. If
you want to add ‘live’
commentary whilst editing,
it can be frustrating if you
make a mistake as the
whole thing needs to be rerecorded.
It is easier to
record the commentary onto
an audio cassette and then
mix it in on the final copy.
AUDIO
Video
recorder
VIDEO
Camera
in
MUSIC
Cassette
player
Amplifier
CD player
Music
in
Master
out
Sound mixer
Digital audio / convertors
Video
recorder
AUDIO
TV
Microphone
Headphones
Digital audio delay
Plasma/LCD & Projector owners - do
you get frustrated by the lip-synch
errors when viewing? It occurs because
of a delay introduced by the processing
of the picture. The audio doesn’t go
through the same processing hence the
audio appears ahead of the image. If
you use an AV amplifier for your sound
then we have a solution - the Felston DD740 digital audio delay
module. It allows easy adjustable audio delay allowing you to get
everything back in perfect sync. There are two inputs and you can
switch and adjust from your armchair with the supplied remote.
• Dual digital audio inputs and outputs (optical and coax)
• Remote control
• 680ms maximum delay (340ms for 96kHz signals)
• Automatic input switching, with input's last delay restored
• Can convert optical-to-coax/coax-to-optical, for connecting 2 sources
to an amplifier with a single input
• 12 user-programmable presets (6 per input)
• Adjustable display brightness
• Discrete IR commands for integration with learning remotes
• No effect on audio quality thanks to bit-perfect reproduction
[DD740] £129.00
Digital audio convertor
A universal digital audio convertor that
will change digital optical signals
(Toslink) to coaxial and vice-versa.
Supplied in a screened case with UK
power supply.
[BT992] £19.99
38
all prices include VAT
Order by Tel: 01332 830550 or Fax: 01332 830551