QED A270 Signal Path Optimised Stereo Amplifier Instructions

Instructions
A270 Stereo Amplifier

MAINS CONNECTION (1)

Either a standard 13 Amp mains plug (fitted with a 3 Amp fuse) or a QED miniature 6 Amp mains plug (see recommended accessories) needs to be fitted to the mains cable in accordance with the instructions.
BROWN to live (L), BLUE to neutral (N), and GREEN to earth-

LOUDSPEAKER CONNECTION
(2) = DIRECT
(3) = SWITCHED
For the best sonic performance, we recommend that the negative “GROUND” (black terminals) and the positive “DIRECT” (red terminals) are used. The type of terminals fitted is 4m.m. sockets so it will be necessary to use cables with 4m.m. plugs fitted (see recommended accessories). Should you require the loudspeakers to be switched off when the headphones are inserted, it will be necessary to change from the red terminals to the white “SWITCHED” terminals.

81-WIRING

Some loudspeakers are now fitted with FOUR terminals. These permit a separate feed from the amplifier to the ‘treble’ and ‘bass’ drivers in the loudspeaker. Such a configuration offers a significant improvement in sound quality.
The A270 is fitted with two sets of loudspeaker sockets to facilitate such a bi-wire connection.

PRE-AMPLIFIER OUTPUT (4)

D.A.T. CONNECTION
(5) = PLAYBACK
(6) = RECORD
This is for both the record and playback connection of a D.A.T. recorder (or 2nd tape deck).
TAPE CONNECTION
(7) = PLAYBACK
(8) = RECORD
This is for both the record and playback connection of a tape recorder.
VIDEO INPUT (9)
This allows the audio output of a video recorder to be connected to the amplifier.
TUNER INPUT (10)
This is for the connection of a radio tuner such as the QED T260 three-wave band tuner.
COMPACT DISC INPUT (11)
This is for the connection and correct attenuation of a Compact Disc player.
MOVING COIL DISC INPUT (12)
This input is for the connection of a suitable high-quality turntable with a moving coil cartridge (internally switched see Super Analogue section).

MOVING MAGNET DISC INPUT (13)
This input is for the connection of a suitable high-quality turntable with a moving magnet cartridge.
EARTH TERMINAL (14)
This is for the connection of the earthing wire from the turntable.
‘LISTEN’ SELECTOR SWITCH (15)
This switch selects the signal source which is to be amplified and fed through to the speaker terminals.
‘RECORD’ SELECTOR SWITCH (16)
This switch is used for recording only and selects the required signal source which is then directed to the recording inputs of the tape deck or D.A.T. recorder (or 2nd tape deck).
With the ‘listen’ and ‘record’ switching system, it is possible to record from one signal source whilst listening to another.
VOLUME CONTROL (17)
This is used as a normal volume control except when channel balancing is required. To adjust channel balance, hold the inner knob stationary and turn the outer knob clockwise to increase left channel volume, or anti-clockwise to reduce left channel volume. Fully anti-clockwise is zero volume.
HEADPHONE SOCKET (18)
This is a standard 1/4 inch stereo jack socket and is suitable for use with most headphones.
MAINS POWER SWITCH AND INDICATOR (19)
This switches the amplifier on and off. When the LED is illuminated, the amplifier is ON.
INITIAL OPERATION
Having covered all the connections and controls of the QED amplifier, you are now ready to switch on, but first turn the volume control to zero and select the ‘Listen’ switch the signal source of your choice. Now switch on. The LED should illuminate, indicating that the mains power is on. Turn the volume control clockwise to the required level and just listen, relax and enjoy the music!
SWITCH ON DELAY
To avoid a loud turn-on thump through the speakers, a switch-on with a delay of about 10 seconds is incorporated. A harmless low-level “click” will however be audible.
OUTPUT PROTECTION
The normal type of signal degrading fuses has been omitted in favour of a very special type of non-sound degrading electronic protection circuit. This circuit has been carefully developed to only operate under fault or actual overload conditions.
SUPER ANALOGUE DISC INPUT
The SUPER ANALOGUE disc input circuit is a fully discrete transistor (no I.C.’s) multiple-stage disc input design complete with its own dedicated power supply regulation circuits.
It is factory set to ‘moving magnet’ (m.m.) operation. To change to ‘moving coil’ (M.C.), it is necessary to remove the amplifier’s cover and re-set the S.A. Board switches. The switch positions are ‘down’ for the moving magnet and ‘up’ for the moving coil. If in doubt consult your QED Hi-Fi Dealer.
The SUPER ANALOGUE circuit is a quite superb design capable of doing justice to some of the very best Turntable/Arm combinations available.

GENERAL INFORMATION

For optimum results, we recommend that the amplifier is allowed a 3 – 4 minute “warm-up” period. We also recommend that a space of at least 25mm is left between the back of the amplifier and the wall behind it.
RELIABILITY
This product is manufactured in QED’s own factories at Ashford and West Drayton in Middlesex (London) England. The computer-controlled testing and quality control program covers an individual before and after the “soak” testing procedure followed by a final “listen” to the product. We believe that these thorough tests will ensure a trouble-free operation.

TECHNICAL SPECIFICATION

A270

NOTE: The above specifications may vary from country to country, but are correct for the U.K. market.

GUARANTEE

The A270 is covered by a 2-year guarantee for both parts and labour. To qualify for the 2nd year, it is necessary to return the guarantee card to the QED factory.
We operate a policy of continuous improvement and reserve the right to amend designs and specifications without prior notice.

RECOMMENDED ACCESSORIES

SECTION PRODUCT
SPEAKER CONNECTION
Supplied with the A270 are QED P79 4mm plugs. Use only these plugs for speaker cable connection. On no account use metal bodied plugs or push bare wires into the socket.
SPEAKER CABLE For the best results, we recommend the use of a QED flat 79 strand speaker cable. (or F200) WARNING: Use only genuine QED speaker cables.
Tape, Tuner, C.D. Aux, & D.A.T. connections. Use QED INCON interconnect cables.
QED HIFI SYSTEMS DIVISION, UNIT 12, ASHFORD INDUSTRIAL ESTATE, SHIELD ROAD, ASHFORD, MIDDLESEX, ENGLAND.
WARNING: This amplifier is not suitable for LITZ-type high capacitance speaker cables or electrostatic loudspeakers. Use of either will result in amplifier damage for which we will not be liable.
QED reserve the right to amend designs and specifications without prior notice.

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