Electro-Dan SS20202014 User manual

Electro-Dan
SS20202014
Surround Sound Amplifier
User Manual

Page 2 of 11
Introduction
The Electro-Dan SS20202014 (SS Triple-20, 14) is a complete
Surround Sound Preamplifier, decoder and Power Amplifier all in
one box. A stereo input, mains input and a further 4 or 5 speakers is
all that is needed to complete a home cinema system.
Features:
•20Wper channel RMS* power to front left and right channels.
•20WRMS*power to rear channel.
•14WRMS*power to centre channel.
•Pre-amp with loudnessfilter and tone controls.
•Matrixsurround sound decoder with centre channel output.
•Level controls for front, rear and centre channels.
•Power switches for rear and centre channel amplifiers.
•Headphone output and switch.
•Inputs for external decoders** (i.e. 5.1 Dolby® Surround Sound).
•Centre and Subwoofer pre-outs.
•Temperature Controlled cooling Fan
* RMS power refers to the true power ofan amplifier, itis obtained bytheRMS
voltage and RMS current atthe output.
** The rear pre-in is onlyMono (1 channel). A stereo input is provided, but the unit
will convert this to mono internally.

Page 3 of 11
Operating the system
The SS20202014 hasmains input and output sockets. These are in
the form ofEuropean style 3-pin connectors.
WARNING:
These connectors carrymains voltage of230-250V AC and it will kill
you ifcare and consideration is not taken!
ATTENTION:
The units input must be properlyEarthed (Grounded), failure to do
so mayresult in electric shock!
Wiresused in the 3-pin connector:
Brown: Live
Blue: Neutral
Green/Yellow:Earth
This unit must also be fused with a 3 Amp (Red) fuse rated at 250V
AC.
Mains Outlet
There is a mains outlet socket. This can be used for switching an
external appliance. The appliance must have the appropriate plug
and must not have a current greater than 2 amps absolute
maximum (This is about 500 Watts). Remember that the appliance
will onlybe able to operate when the Surround Amplifier Unit is
switched ON. Ifin doubt, plug the appliance into a house mains
socket (or rated trailing socket).
Fuses
In the event ofa failure, two fuses are used to protect the unit from
damage. Observe the ratings ofthese fuses. These should be
T0.4A (Time delayglass fuse rated at 250V AC) and F0.2A (Quick-
blowglass fuse rated at 250V AC).

Page 4 of 11
SafetyPrecautions
The SS20202014 is like manyother electricalunits and safetymust
be assessed for safe and reliable use.
•NEVER REMOVE THE COVER OFF THIS UNIT– MAINS
VOLTAGES ARE INSIDE! DO NOTMODIFY!
•IF QUALIFIED FOR SERVICE, REMOVE THE MAINS PLUG
FIRSTBEFORE OPENING THE COVER!
•KEEP THE UNITWELL AWAY FROM MOISTURE AND HUMID
AREAS!
•DO NOTUSE THE UNITOUTSIDE AND KEEP ITAWAY
FROM DIRECTSUNLIGHT!
•DO NOTSUBJECTTHE UNITTO SHOCK!
•ALWAYS EARTH THE APPLIANCE WITH A SUITABLE, MAINS
RATED EARTH CONNECTION!
•DO NOTSTORE THE UNITIN A VERY LIMITED SPACE – IT
MUSTBE ABLE TO ‘BREATH’ AND NOTHING SHOULD
BLOCK THE FAN INLET!
•DO NOTSPILL LIQUID ON THE UNIT!
•KEEP THE UNITAWAY FROM AREAS OF HIGH DUST!
•DO NOTUSE NEAR OPEN OR NAKED FLAMES!
•IF PROBLEMS EXIST, TRY KEEPING THE UNITAWAYFROM
MAGNETIC FIELDS (i.e. loudspeakers) AND RF EQUIPMENT
(i.e. TV’s and radios)!

Page 5 of 11
•DO NOTPOKE THE UNITWITH SHARP OR THIN OBJECTS!
Hooking Up the SS20202014
The unit is designed to decode a stereo signal, usuallyfrom a TV,
VCR or similar appliance. It
will also accept signals from
Hi-fi equipment (i.e. CD
players) or even personal
stereos. A Mono input can
onlybe used once it is split
into two channels bya
splitter. Note that rear
surround sound doesnot
work with mono inputs.
If your TV or VCR does not
have Phono line outputs but
does have a spare SCART
socket, then special
adapters can be used to
convert the SCARTsocket to
three phono plugs (Video,
audio left and audio right).
The audio left and right
(coloured white and red
respectivelyis what this unit
requires).
Left is a rear diagram for the
amplifier unit:
If you own a DVD player,
separate decoder or home
computer that has analogue
outputs for surround sound,
then this unit can use them

Page 6 of 11
to improve the decoding ofthe surround sound. On some DVD
players there are line outputs for surround sound (usuallyDolby®
Digital 5.1 Surround Sound).
Using the correct lead, these outputs can be plugged into the pre-
inputs ofthe SS20202014. For the rear channel, a
lead with two phono
sockets to a 3.5mm
stereo jacksocket is
required, shown left:
For the centre channel,
a similar lead is
required but it onlyhas
to be mono and
therefore mayhave one
phono socket and a
mono 3.5mm Jack Plug.
Some multimedia personal computers nowcome with quad or 5.1®
outputs. These can also be used, However the leads are more likely
to be jack-to-jack plugs.
Note that when you push in and pre-in jack plug, the internal
decoding is disabled, but you can still use the level controls on the
front for adjustments. The volume controls will not however adjust
the volume of rear and centre pre-ins.
Setting up your speakers
Nowthat you have plugged in the mains and inputs, you nowhave
to set-up the speakers.
The optimum surround sound uses two front speakers, correctly
wired up for left and right audio, a centre speaker which is placed in
the middle of the two front speakers and a two rear speakers which

Page 7 of 11
are placed behind the listening position. The diagram belowshows
the layout.
To ensure the long term reliabilityofyour surround amplifier, certain
criteria needs to be looked at for loudspeaker selection. The table
belowlooks at the impedance of the loudspeakers on each channel.
Channel Impedance
Front Right 4 ohms to 16 ohms(Min/Max)
Front Left4 ohms to 16 ohms(Min/Max)
Rear Left 8 ohms to 16 ohms(Min/Max)
Rear Right 8 ohms to 16 ohms(Min/Max)
Single Rear 4 ohms to 16 ohms(Min/Max)
Centre 4 ohms to 16 ohms(Min/Max)
Note: The table includes data for a single rear channel. The rear
maybe set up with just one speaker (plugged in either the left or
right outputs, not both), which can be placed directlybehind the
listening position. This effect is not as good as twin rear speakers,
but it does allowa 4-ohm speaker to be used.
Front speakers should be rated at 20Weach or more, rear speakers
(twin) should be rated at 10Weach unless there is a single rear

Page 8 of 11
which should be 20Wminimum. The centre speaker should be rated
at 15Wminimum. For best results, use speakers that are matched
for best sensitivity.
Cable used should be capable of passing the required power.
Thicker, higher qualitycable will give better results.
Warning:
The centre speaker and the front speakers must be magnetically
shielded iftheyare placed near a Television. If this is not observed,
the cathode raytube inside the TV will suffer.
Listening to theSS20202014
When you first listen to you surround sound amplifier; you need to
adjust it to the settings you prefer. Connect it up to you TV, VCR
etc. and find a good movie! More recent movies have the best
surround sound codingand these should be used.
If you are using the internal decoder, you mayadjust the volume,
bass, treble and use the loudness to suit your needs on all
channels. A good test movie should make use ofall frequencies so
you can adjust the bass and treble to the best possible preference.
The loudness can be used to increase the high and lowfrequencies
slightlywhen listening at lowvolumes.
You will notice that when there is speaking, sound onlycomes from
the front and centre channels. When there is action or music in the
movie, there should be sound from the rear channel. If this is not so,
make sure you are feeding the unit with a stereo signal (i.e.
NICAM® or that the movie is not old (and therefore onlymono).
Modern music is also stereo and this surround sound unit can add
another dimension to manytypes of music from rock, pop to recent
classic.

Page 9 of 11
When listening, the centre speaker should be adjusted to the point
where you can ‘just’ hear it. This is the optimum setting for many
movies and music. Too loud and you will not get the stereo front
image and also overload the centre amplifier or speaker much
easier when the volume is turned up.
Turning off the rear and centre amplifiers
When listening to music (for instance), you maynot want the rear or
centre channels (or both). Two toggle switches on the front ofthe
unit allowyou to disable the amplifiers for the rear and centre
channels, and hence remove the sound.
You maywant to also disable the rear channel if you are listening to
mono sound (which saves power and improves the life ofthe rear
amp).
Private listening
A pair of headphones can be plugged into the 6.35mm jack at the
front of the unit. To use the headphones, press the headphone
selector switch (next to the jack socket) and the sound to the front is
cut and passed to the headphonesinstead.
Note that although the power is cut when headphones are used, the
output ofthis unit is still sufficient enough to destroymost
headphoneswhen the volume is turned up, so keep the volume low
at all times, especiallywhen switching to the headphonesfrom
normal listening.
When switching to headphones, the front left and right is cut, but the
centre and rear channels remain active. To disable these, use the
toggle switches as described above. When allchannels are
disabled, you maylisten privately!

Page 10 of 11
Troubleshooting
•The unit has no sound and the LED indicator is not lit.
Did you press the power switch? Check the power, is it
connected? If so, check the fusesin the mains plug and the unit
and replace anythat have blown.
•The unit has no sound, but the LED indicator is clearlylit.
Check the volume, is the main volume sufficient? Check the
individual channel levels, are theysufficientlyturned up? Is the
headphone switch pressed in and the rear and centre power
switches switched up. Ifall is true, checkthe inputs. Is the
source on and working and is the input lead securelyconnected?
•The sound is distorted.
Reduce the volume on the main unit or on the source.
•One (or more) ofmyspeakers is not working.
Check the connectionsto the speaker(s) and the surround
amplifier unit. Are theysecure and are theyproperlyconnected
(+ and -)? Checkthe speaker(s) with another amp to see if it is
blown.
•The sound cuts out.
The unit is too hot, turn it off. Ifproblems persist, consult dealer
or manufacturer.
•The fan does not spin.
The fan onlyspins when the unit gets hotter.
•I’ve just be killed bythe unit
You did NOTproperlyEARTH the unit, make sure it is properly
earthed in your next life!
Table of contents