What is stereo?




There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.




H.H. Scott '59





Arcam Alpha 2 Tuner

 The Arcam Ralpha 2
This tuner has successfully established a distinctly “British” identity, with attractively classic ergonomics. A modest price plus sound quality comfortably better than most are further reasons for a “best buy”

The diversity and quality of modern broadcasting is demanding new levels of performance from today’s hi-fi tuners. In particular, a natural, clear and dynamic sound from FM coupled with the versatility of MW and LW reception of popular programmes, are the criteria most desired by serious music lovers and audiophiles. The Arcam ALPHA 2 STEREO TUNER FROM a&r Cambridge admirably fulfills thee requirements at an economic price.

Versatility
The tuner has been designed to provide the highest quality reception of programmes transmitted on both the FM/VHF and AM broadcast bands. Although suitable for use with all quality stereo amplifiers, the Alpha 2 tuner is specifically styled to match with both Arcam’s outstandingly successful 30 watts per channel Alpha 2 amplifier and the high performance electronics in our. Delta series

 Ease of operation
The tuners controls have been deliberately kept to a minimum to ensure simple, fuss free operation. Three interlocked push buttons are used for selection of the wavebands, each band using the rotary tuning control for precise tuning. Additionally, for FM reception, an AFC switch is fitted to compensate for small frequency drifts or slight mistuning which may occur. A mono switch is provided to ensure better reception of weak stations. A red LED beacon indicates when a stereo programme is being received. The large rotary tuning control is fly-wheel assisted to produce an excellent “feel” and is coupled to an extended analogue tuning scale, featuring a unique dual role frequency pointer. On MW and LW the pointer glows green but on FM it doubles as a precise tuning indicator, changing colour in traffic light sequence as it moves onto a station and turning green when the station is exactly on tune. Station markers are provided to indicate the position of favourite programmes.

Design
The design has been realized using high quality components selected for optimum sonic performance. Detailed theoretical analysis and extensive listening has produced exceptional results, the sound quality in particular on FM being firm, precise and without annoying sibilance. The use of a “birdie” filter fitted before the stereo decoder considerably reduces the unpleasant whistles caused by closely positioned stereo broadcasts. On the long and medium wvebands careful design has improved reception especially on the “crowded” night time airwaves, and results in a clearer, more informative sound.
 Quality and reliability
Great care has also been taken in every aspect of the design, construction and lignment of the Arcam Alpha 2 tuner to ensure years of consistent, trouble free operation. All componemts are operated well within their ratings. Internal wiring and connectors are all but eliminated by mounting all components (except indicators) on a single glass fibre Printed Circuit Board. Every tuner is rigorously checked at all stages of production, both for performance and appearance. All are tested and aligned using advanced custom built equipment and finally ‘burnt in” and retested before dispatch to ensure ultimate reliability.
The Arcam Alpha 2 tuner is provided with a ready made 75 ohm dipole wire aerial for FM reception and a specially designed loop aerial for AM use. Nevertheless, for best results, in areas of anything but prime reception, it is nearly always better to add appropriate external aerials in order to provide the tuner with the best possible input signal. 
Specifications
FM Tuner Section
Tuning Range:  87,5 - 108 MHz
Sensitivity:  1,4 µV (IHF)
Total Harmonic Distortion (95 MHz ref. 22,5 kHz dev. At 1 kHz):
Mono :  better than 0,15%
Stereo :  better than 9,25%
Signal-to-Noise Ratio:
Mono :  better than 70 dB
Stereo:  better than 68 dB
Frequency Response:  20 Hz - 12 kHz ±0,5 dB; typically -2 dB at 15 kHz
Channel Separation (1 kHz): better than 40 dB
Pilot Tone Syppression:  better than 50 dB
Capture Ratio:  1,5 dB
Alternate Channel Selectivity:  better than 60 dB
AM Suppression:  better than 50 dB
AM Tuner Section
Frequency Range: 
MW range :  530 - 1600 kHz
LW range :  160 - 270 kHz
Distortion:  0,4% at 50% modulation
Signal-to-Noise Ratio:  50 dB (CCIR weighted) ref. 30% modulation
General Section
Output Impedance:  1,8 k Ω
Recommended Load:  20 k Ω or greater
Output Level:  800 mV at 75 kHz deviation
Spares Kit:  FM ribbon aerial; AM loop aerial; phono-phono lead; station markers
Power Supply:  200 - 250 V AC, 6 VA (100 - 120 V AC conversion possible)
Dimensions (W x H x D):  430 x 84 x 230 mm (16,9 " x 3,3" x 9,1")
Weight:
Net :  2,6 kg (5,7 lb)
Packed :  3,2 kg (7,0 lb)

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