Alpha 3 amplifier handbook
Arcam Alpha 3 handbook
Introduction
The Arcam Alpha 3 integrated stereo amplifier has been
designed to provide a combination of high quality sound reproduction and
sophisticated styling. The Alpha 3 amplifier has five inputs for turntable,
compact disc player, tuner, video sound output and tape recorder.
The Alpha 3 provides outputs for both speakers and
headphones, and produces low level signals suitable for recording on to tape.
Although designed for simplicity of operation the Alpha 3 has comprehensive
tone control facilities which enable good results to be obtained with a wide
variety of programme material.
A matching Alpha tuner, Compact Disc player and Alpha
speakers are also available. Please ask your dealer or distributor for full
details, or write to Arcam at the address shown at the end of this booklet.
Installing and using vour Alpha 3 equipment
Mains connections
Check that the voltage setting of the amplifier, as indicated on
the back panel, is the same as the local mains supply. The wires in the mains
lead are coloured in accordance with the following code:
Green and yellow - Earth
Blue - Neutral
Brown - Live
As the colours of the wires in the mains lead may not
correspond with the coloured markings identifying the terminals in your plug
proceed as follows;
The wire which is coloured green and yellow must be
connected to the terminal in the plug which is marked by the letter E or by the
safety earth symbol or coloured green or green and yellow. The wire which is
coloured blue must be connected to the terminal which is marked by the letter
N or coloured black or blue. The wire which is coloured brown must be
connected to the terminal which is marked by the letter L or coloured red or
brown.
Export units for certain markets have moulded mains plugs
fitted as standard. If the mains plug is fused fit a 5 amp fuse for the Alpha 3
amplifier.
The AC supply inlet to the Alpha 3 amplifier uses a standard
I EC chassis mounting plug. The lEC line socket on your mains lead and the
I EC plug on the Alpha 3 units are a tight fit; before first using an Alpha 3
amplifier it is therefore important to ensure that the socket is pushed firmly
home into the chassis plug.
Rear panel connections
Please refer to diagrams on inside of rear cover
All inputs and tape outputs are via RCA phono connections.
For most equipment, the right hand channel output is
indicated by a red plug, and the left hand channel by a black or white plug.
Disc Input
This input is only suitable for use with turntables fitted with a
moving magnet or high output moving coil cartridge. If your turntable is fitted
with a low output moving coil cartridge you will need to use some form of
external step-up device (a transformer or head amplifier) between the cartridge
and the Alpha 3. If your turntable is fitted with a flying earth lead, connect it to
the ground terminal directly above the disc input. Nevertrv to use any other
audio equipment (such as a CD player or tape deck) through the disc input.
The input will be overloaded and the sound will be badly distorted.
CD, Video and Tuner inputs
These inputs may also be used as general purpose inputs for
sources with a line level output, such as a second tape recorder.
Tape input / output
Signals can be received from the line output, and sent to the
line input of a tape recorder via these sockets.
Speaker outputs
The speaker outputs will drive speakers within the range of
4 to 16 ohms impedance. The speaker binding posts will accept bare wires or
4 mm banana plugs. The speaker cable’s positive conductor must be
connected to the red terminals, and the negative conductor to the black
terminals. The positive conductor of the cable is usually marked as such, or
may have a ridge running down the length of the outer insulation.
When fitting 4 mm plugs, ensure that the positive conductor is
connected to the red plug, and the negative conductor to the black plug. When
using bare wires, strip back approximately 12 mm, (1/2") and twist the bare
ends tightly. Unscrew the binding post and insert the wire underneath, then
tighten. Check that no stray strands can short to other terminals, or to the
chassis.
Operating two pairs of speakers
If desired, it is possible to operate two sets of 8 ohm
impedance (or higher) speakers with the Alpha 3 amplifier. One pair is
connected to the ’direct’ speaker terminals, and the second pair is connected
to the ’switched’ terminals.
page 2
Arcam Alpha 3 handbook
the time. The pair connected to the ’switched’ terminals can be muted by
The speakers connected to the ’direct’ terminals will work all
inserting a 1/4" (6.35mm) jack plug into the headphones socket on the front
panel of the amplifier. This jack plug can be stereo or mono, and need not be
connected to anything to operate the speaker mute switch.
Bi-wiring
, If your speakers are bi-wirable, you can conveniently use both
pairs of speaker terminals on the Alpha 3 to bi-wire your speakers, and
improve the sound of the system. Alternatively, the cable runs to each speaker
can be commoned together at the amplifier end, in order to leave a set of
terminals free to drive a second pair of speakers.
Speaker fuses
These are 2 amp fast blow 20mm fuses fitted internally. They
may blow if the amplifier is run continuously at very high level into the correct
speaker load, or run at high level into a speaker of too low an impedance
(usually less than 4 ohms), or used to drive two sets of low impedance
speakers, or run into a short circuit.
They are user-replaceable, and a spare fuse is provided
inside the amplifier. However, if they blow consistently in the absence of any of
the above conditions, please consult your dealer.
The speaker fuses are located inside the amplifier next to the
speaker terminals. If a fuse needs to be replaced, first switch off the
amplifier and unplug it from the mains. Remove the cover by unscrewing
the two screws on the top of the cover. Lift the cover slightly, and slide it out
towards the rear of the unit. The damaged fuse can now be removed.
Replacement of a new fuse is simply the reversal of this procedure. Do not
replace with a fuse of greater value than 2 amps (or with a ’slow blow’ or
’anti-surge’ type) since this will endanger both the amplifier and your speakers.
This will also invalidate your guarantee.
Front panel controls
Please refer to the diagrams on inside of rear cover
Input selector switch
The input selector switch, which is situated on the far left of
the front panel, selects which input signal is fed to the speakers and
headphones. The selected signal is also fed to the tape ’out’ sockets.
Tape monitor switch
The tape monitor switch is generally left in the ’off position
(switch out), so that the programme selected by the input switch is routed to
the speakers. When the tape monitor switch is depressed, the return signal
from the tape recorder is routed to the speakers.
The tape monitor switch also allows off tape monitoring if a
three head tape machine is being used. By depressing the switch the signal
recorded onto tape can be routed to the speakers, allowing direct A/B
comparisons as the recording is made. With the tape monitor switch
depressed the off-tape signal is the only signal available to the speakers.
Direct switch
When this switch is pressed in, the bass, treble and balance
controls become inoperative. The purpose of the direct switch is to bypass
these circuits. This can result in a slightly clearer and more dynamic sound.
This can be particularly effective when using the Alpha 3 with a top quality CD
player, but the action of the switch takes place on all inputs, not just the CD
input.
Volume
The volume control adjusts the sound level for both the
speakers and the headphones.
IMPORTANT!
BEFORE REMOVING THE COVER, ALWAYS SWITCH OFF THE
AMPLIFIER and UNPLUG IT FROM THE WALL SOCKET.
page 3
Bass
The bass control cuts low frequencies when turned anti
clockwise and boosts them when turned clockwise. The flattest response is
obtained when the control is in the centre ’click’ position.
Treble
The treble control cuts high frequencies when turned
anti-clockwise and boosts them when turned clockwise. The flattest response
is obtained when the control is in the centre ’click’ position.
Arcam Alpha 3 handbook
Balance
The balance control is used to move the stereo sound image
to the left or right. It can be used to compensate for imbalance in room
acoustics or input signals.
Headphones socket
The headphones socket accepts any dynamic headphones
fitted with a standard 1/4 inch (6.35mm) stereo jack plug. If your headphones
are fitted with a smaller jack (usually 3.5 mm), your dealer can supply a
suitable adaptor. The headphones may mute the speakers, or not, as required
(see Operating two pairs of speakers, page 2). This output is not suitable for
driving most electrostatic headphones.
Power
The amplifier is turned on by pressing the mains power
switch. The green light indicates that the power supply in the amplifier is
operating - it will continute to glow for a short time after the amplifier has been
switched off. A gentle ’click’ or ’pop’ may sometimes be heard shortly after
turning the amplifier off. This is perfectly normal, and will not harm your
speakers.
Tape recording and replay
The tape input/output is designed to suit most reel-to-reel and
cassette tape recorders.
Recording
Select the signal source to be recorded using the selector
switch (disc, tuner, CD or video). Then set the correct recording leveis on your
tape recorder and switch it into ’RECORD’ mode.
During recording the volume and tone controls have no effect
on the signal being sent to the tape ’out’ sockets.
Replay
Depress the tape monitor switch and then switch your tape
recorder into ’PLAY’ mode.
Connecting cables
We strongly recommend the use of quality speaker and
interconnect cables with your hi-fi system. The better the components used in
your system, the more important it becomes to match them with good cable.
We have found interconnect and speaker cables from the AudioQuest range to
be particularly suitable. Detailed information on the AudioQuest range of
cables may be obtained from your dealer or the factory.
Hints and Tips
Follow the manufacturer’s instructions on the placement of
speakers for the best results. Generally, speakers should be mounted on
dedicated stands, and sited away from corners.
Always ensure that the speaker cable is connected securely
to the output terminals, with no loose strands of wire, and that the mains
connections are tight and fully home in their sockets.
Keep the turntable away from the speakers to avoid acoustic
pickup by the turntable from the speakers - they should not be placed on the
same piece of furniture.
The amplifier will get quite warm when being used at high
levels. This is perfectly normal. However, if it becomes too hot to touch, switch
off the amplifier at once and consult your dealer.
If there is a lot of hum with the disc input selected, check that
the earth lead from the turntable is connected to the ground terminal just
above the disc input sockets, and that the amplifier is correctly earthed via the
mains lead.
Ensure that the amplifier is not directly underneath the
turntable, or next to any unit containing a large mains transformer! (Check by
moving the unit and assessing whether the hum level changes).
If your system does not work check that:
1. The amplifier is switched on and the green LED is on.
2. The source is plugged into the correct input sockets.
3. The selector switch is switched to the correct source.
4. The speakers are connected to the amplifier correctly.
5. The tape monitor switch is not ’in’ when trying to use
another input.
6. The volume control is not set to minimum.
7. The speaker fuses have not blown.
8. The fuse in the mains plug has not blown.
If sound comes out of one speaker only check that:
1. Both speakers are connected to the amplifier correctly.
2. The balance control is not set fully clockwise or anti
clockwise.
3. Both left and right channels of the source are connected to
the inputs correctly and the input wiring is not faulty,
(check by swapping left and right input connectors).
4. A speaker fuse has not blown.
page 4
Arcam Alpha 3 handbook
Balance
The balance control is used to move the stereo sound image
to the left or right. It can be used to compensate for imbalance in room
acoustics or input signals.
Headphones socket
The headphones socket accepts any dynamic headphones
fitted with a standard 1/4 inch (6.35mm) stereo jack plug. If your headphones
are fitted with a smaller jack (usually 3.5 mm), your dealer can supply a
suitable adaptor. The headphones may mute the speakers, or not, as required
(see Operating two pairs of speakers, page 2). This output is not suitable for
driving most electrostatic headphones.
Power
The amplifier is turned on by pressing the mains power
switch. The green light indicates that the power supply in the amplifier is
operating - it will continute to glow for a short time after the amplifier has been
switched off. A gentle ’click’ or ’pop’ may sometimes be heard shortly after
turning the amplifier off. This is perfectly normal, and will not harm your
speakers.
Tape recording and replay
The tape input/output is designed to suit most reel-to-reel and
cassette tape recorders.
Recording
Select the signal source to be recorded using the selector
switch (disc, tuner, CD or video). Then set the correct recording leveis on your
tape recorder and switch it into ’RECORD’ mode.
During recording the volume and tone controls have no effect
on the signal being sent to the tape ’out’ sockets.
Replay
Depress the tape monitor switch and then switch your tape
recorder into ’PLAY’ mode.
Connecting cables
We strongly recommend the use of quality speaker and
interconnect cables with your hi-fi system. The better the components used in
your system, the more important it becomes to match them with good cable.
We have found interconnect and speaker cables from the AudioQuest range to
be particularly suitable. Detailed information on the AudioQuest range of
cables may be obtained from your dealer or the factory.
Hints and Tips
Follow the manufacturer’s instructions on the placement of
speakers for the best results. Generally, speakers should be mounted on
dedicated stands, and sited away from corners.
Always ensure that the speaker cable is connected securely
to the output terminals, with no loose strands of wire, and that the mains
connections are tight and fully home in their sockets.
Keep the turntable away from the speakers to avoid acoustic
pickup by the turntable from the speakers - they should not be placed on the
same piece of furniture.
The amplifier will get quite warm when being used at high
levels. This is perfectly normal. However, if it becomes too hot to touch, switch
off the amplifier at once and consult your dealer.
If there is a lot of hum with the disc input selected, check that
the earth lead from the turntable is connected to the ground terminal just
above the disc input sockets, and that the amplifier is correctly earthed via the
mains lead.
Ensure that the amplifier is not directly underneath the
turntable, or next to any unit containing a large mains transformer! (Check by
moving the unit and assessing whether the hum level changes).
If your system does not work check that:
1. The amplifier is switched on and the green LED is on.
2. The source is plugged into the correct input sockets.
3. The selector switch is switched to the correct source.
4. The speakers are connected to the amplifier correctly.
5. The tape monitor switch is not ’in’ when trying to use
another input.
6. The volume control is not set to minimum.
7. The speaker fuses have not blown.
8. The fuse in the mains plug has not blown.
If sound comes out of one speaker only check that:
1. Both speakers are connected to the amplifier correctly.
2. The balance control is not set fully clockwise or anti
clockwise.
3. Both left and right channels of the source are connected to
the inputs correctly and the input wiring is not faulty,
(check by swapping left and right input connectors).
4. A speaker fuse has not blown.
page 4
Arcam Alpha 3 handbook
Technical specification
Alpha 3 amplifier
CD, tuner, tape and video
Sensitivity 170mV
Signal to noise ratio (CCIR) 95dB
Input impedance 20k ohm
Overload margin 30dB.
(Noise and sensitivities ref. 40W into 8 ohms at 1kHz.;
OUTPUT POWER (typical)
Both channels driven
Into 8 ohms 40W. (20Hz-20kHz at 0.5%THD)
Single channel driven at 1kHz
Into 8 ohms SOW typical. Into 4 ohms 80W typical.
Harmonic distortion
At SOW, 8 ohms at 1kHz 0.02% typical.
FREQUENCY RESPONSE Disc input
Typically +/- O.SdB 60Hz - 20 kHz, -3dB at 20Hz.
Other inputs
Typically +/- 0.5 dB 10Hz - 20 kHz.
Tone Controls
Maximum variation +/-5 dB at 50Hz and 15 kHz.
INPUTS
Disc
(suitable for MM and ’high-output’ MC cartridges.)
Sensitivity 2.2mV, impedance 47k ohm/1 OOpF.
Signal to noise ratio (CCIR) 75 dB.
Overload margin 33 dB.
OUTPUTS
Tape output
Nominal output level 150mV, impedance 2k ohm
Headphones
Maximum output level into 600 ohms 10V rms. Output
impedance 330 ohms. Suitable for heaphones of 8 ohms
to 2k ohms impedance.
Loudspeakers
Nominal output level 40W per channel. Suitable for
speakers of 4 ohms or higher nominal impedance.
GENERAL
Power supply
240V nominal, 230VA max. May be dealer adjusted to 220V
and 120V nominal. (100V models to special order)
Internal mains fuse
800mAT (slow blow) for 240V or 220V operation.
1.6AT (slow blow) for 120 V or 100V operation.
The internal mains fuse is not user replaceable.
Size (overail)
430 mm W X 248 mm D X 84 mm H.
Weight
4.0 Kg. nett.
4.6 Kg. packed.
page 5
E. &OE.
Arcam Alpha 3 handbook
Guarantee for UK sales
This equipment has been fully tested and a full record of these
tests made before despatch from the factory. Both the workmanship and the
performance of this equipment are (except as set out below) guaranteed
against defects for a period of two years from the date of purchase, provided
that it was originally purchased from an authorised UK dealer under a
consumer sale agreement. ( The words "consumer sale" shall be construed in
accordance with Section 15 of the Supply Of Goods (Implied Terms ) Act
1973 ).
The manufacturers can accept no responsibility for defects
arising from accident, misuse, abuse, wear and tear, neglect or through
unauthorised adjustment and/or repair, neither can they accept responsibility
for damage or loss occuring during transit to or from the person claiming under
this guarantee.
This guarantee covers both labour and parts, and is
transferable to subsequent purchasers, but the liability of the manufacturers is
limited to the cost of repair or replacement of the defective parts ( at the
discretion of the manufacturers) and under no circumstances extends to
consequential loss or damage.
Guarantee for overseas sales
Equipment not purchased in the UK is generally guaranteed
by the distributor in the country of purchase only. For further details, please
contact your distributor.
Claims under this guarantee
This equipment should be packed in the original packing and
returned to the dealer from whom it was purchased or, failing this, to any other
authorised Arcam dealer. If it is not possible to return the equipment by hand,
then it should be sent carriage prepaid by a reputable carrier. If the original
packing is not available, replacement packing can be purchased from the
manufacturers. The equipment should NOT be sent by post.
If you have any difficulty complying with these requirements,
please contact the manufacturers at the following address:
ARCAM,
Pembroke Avenue,
Denny Industrial Centre,
Waterbeach,
Cambridge,
CBS 9PB,
England.
Telephone; ( 0223 ) 440964
Fax; ( 0223 ) 863384
In either case you should state clearly your name and
address, the date and place of purchase together with a brief description of the
fault. In the event of equipment being returned which, after having been tested,
is found to comply with the published specification, the manufacturers reserve
the right to charge a reasonable fee for testing the equipment, and for the
return carriage.
Enquiries
The manufacturers are happy to answer any queries you may
have regarding the use of this equipment on the condition that this enquiry is
by letter and a stamped addressed envelope is provided. You should state
clearly the serial number of the unit, the dealer from whom it was purchased,
and the date of purchase.
DO NOT CONSIGN THE EQUIPMENT TO ARCAM UNLESS YOU HAVE
BEEN SPECIFICALLY REQUESTED TO DO SO BY THE MANUFAC
TURER’S TECHNICAL SALES OR SERVICE DEPARTMENTS. DO NOT
UNDER ANY CIRCUMSTANCES ATTEMPT TO DISASSEMBLE THE
EQUIPMENT BEFORE DESPATCH.
page 6
THIS GUARANTEE IN NO WAY VARIES OR REMOVES A PURCHASER’S
STATUTORY RIGHTS.
Part number SH018B
Issue 2 10/91
CHANGE OF MAINS VOLTAGE (ALPHA 3 AMPLIFIER)
WARNING - The unit must be unplugged from the mains supply when changing
the wiring or the mains fuses since the fuse is at mains potential even with the
unit switched off.
The Alpha 3 has a multi voltage transformer* so the same transformer can be
used for 240V, 220V and 120V by moving two of the three wires, (orange,
yellow or brown) and changing the fuse rating as necessary. The wire in the
bottom left hand corner determines the mains voltage, i.e. orange for 240V,
and the other two wires go into the holes marked "Spare Wires". The black
wire does not move. The pcb legend is shown below.
240V WIRING (800mA ANTI-SURGE FUSE)
^ BROWN
SPARE WIRES
K YELLOW
s ORANGE
(This wire determines the voltage)
220V WIRING (800mA ANTI-SURGE FUSE)
s BROWN
SPARE WIRES
^ ORANGE
lEI
BLACK
240V ORANGE
220V YELLOW
120V BROWN
lEI
BLACK
240V ORANGE
K YELLOW
(This wire determines the voltage)
120V WIRING (1.25A ANTI-SURGE FUSE)
s YELLOW
SPARE WIRES
^ ORANGE
Ki BROWN
(This wire determines the voltage)
220V YELLOW
120V BROWN
lEI
BLACK
240V ORANGE
220V YELLOW
120V BROWN
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