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





Philips N4450

 The Philips N4450  (1971 -1973) stands rigt at the top of that very select class of tape recorders built specifically for the most discriminating non-professional user. No other does so many things so brilliantly.
To build the N4450, we drew on decades of experience in constructing professional recorders for computer installations, airlines and studios all round the world.
The same experience is behind a complete range of Philips Hi-Fi stereo tape recorders and tape deck/pre-amp.
 Special Featuring
Three motors for perfectly smooth, silent drive and minmum wear - one hall brushless DC motor for capstan drive, two DC motors to drive the reels.
Six heads for forward and reverse - two recording, two playback, two erase.
Tape tension comparators for constant winding torque.
Automatic reverse (continuous reverse as an optional extra). Also manual reverse by pushing a button at any position on  the tape.
Automatic stop at end of tape. Four-digit counter with pushbutton zero reset. Four-digit 'Auto-stop' to halt tape at predeterminated point, with pushbutton on/off switch.
Specification fully according to DIN 45500 Standard, with signal-to-noise ratio better than 48 dB, distortion less than 1%, wow and flutter ±0,15% at 7½ ips, and frequency response 40 - 20,000 Hz at 7½ (within 6dB).
Genuine 2 x 20 watt (RMS) hi-fi amplifier, which you can use with the recorder's motors switched off.  The N4450 can therefore form the heart of a top hi-fi system.
Solenoid-controlled operation for quietness and reliability.
Illuminated tip-touch controls for transport functions and recording mode.
Selector switch for reel size. 10½ reel capacity, metal hub reel locks.
Optional extra unit gives full remote control of transport functions and recording mode, with the same illuminated tip-touch controls as the recorder.
Cursor-type slide switches for function selection - selected function is illuminated.
Precise sliding see-through control for recording and playback.
Pushbutton select filters for rumble, scratch and physiology.
 Mini computer is programmed to 'remember' your instructions - prevents operational errors that might damage teh recorder.
Synchronous clock with built-in device for starting and stopping the recorder at any predetermined time within a 24-hour period.
Sockets for record-deck, rsdio, another recorder, musical instrument, loudspeaker enclosures.
Roller blind at front conceals easily accessible sockets for microphones take in/out and headphones.
Two calibrated, illuminated VU-type meters for recording and playback level indication.
Three speeds: 7½, 3¾ and 1 ips.
Four tracks.
Three-step speed control for fast winding/rewinding.
Levers for cueing during fast wind/rewind.
Splicing device under lower head cover - both head covers easily detachable.
Suitable for horizontal or vertical operation; stereo or mono recording and playback; multiplay; echo during recording; A-B monitoring; mixing; playback and monitoring during recording by means of connected loudspeakers or headphones.
Recording stand-by (recording level adjustable with tape stationary).
Transparent lid has lower part hinged for easy access to controls.

Specifications
Mains Voltages/Frequency:  110-127, 220-240 V;  50/60 Hz
Power Consumption:  min. 29 W/120 W max.
Number of Tracks:  4
Tape Speeds:
7½ ips (19 cm/sec) ±1%
3¾ ips (9,5 cm/sec) ±1%
1 ips (4,75 cm/sec) ±2%
Max Reel Diameter:  10½" (26,5 cm)
Number of Heads:  6 (2 recording, 2 playback, 2 erase heads)
Number of Motors:  4 (one Hall motor - collectorless DC motor - for driving the capstan; two DC motors for driving the reel discs, one synchronous motor)
Wow And Flutter:
7½ ips : 0,15%
3¾ ips : 0,2%
1 ips : 0,35%
Winding Time: 
26 cm reel with LP tape (1080 m) : ≤250 sec
18 cm reel with LP tape (540 m) : ≤150 sec
Input Sensitivities:
Micro :  0,15 mV/2 kohms
Tape :  2 mV/20 kohms (1, 4)
Tape :  100 mV/1 Mohm (3, 5)
Tuner :  100 mV/100 kohms
Phono :  1,5 mV/47 kohms (MD/ceramic HiFi)
Phono :  100 mV (X-tal)
Aux :  2 mV/20 kohms (1, 4)
Aux : 100 mV/1 Mohm (3, 5)
Output Voltage:
Tape ; 1 V/50 kohms
Monitor : 1 V/50 kohms
Headphone : 3 V/400 - 600 ohms
Output Power:  2 x 20 W (distortion at 1%, 8 ohms)
Frequency Range (within 6 dB):
7½ : 40 -20,000 Hz (40 -16,000 Hz with stereofilter)
3¾  : 40 - 15,000 Hz
1 : 60 - 8,000 Hz
Rumble Filter:  -10 dB at 30Hz
Scratch filter:  -15 dB at 15 khz
Physiological Tone Control:
+14 dB at 50 Hz
+6 dB at 10 kHz
Erase Frequency:  100 kHz (±10%)
Dimensions (including Lid):  520 x 500 x 210 mm ( 20½" x 19" x 8")
Weight:  approx 20 kg (44 lbs)



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