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





Sony TC-K44


The Sony TC-K44 incorporates many of the outstanding features of the TC-K-22, including metal tape capability, Dolby noise reduction, and the Tri-Duty DC servo motor. To these, the K44 adds a frequency generator (FG) servo system, for even better tape speed stability, and two other significant features; the Sendust and Ferrite head and LED Peak Program Meters. All told, the TC-K44 is a machine of superior performance capabilities. Yet its price makes it readily accessible to the music lover.

Sendust and Ferrite Head
Sony created the new Sendust and Ferrite head to meet a primary requirement of metal tape; increased flux density. The outstanding characteristic of sendust is its maximum flux density, the highest of any head material. Sendust also exhibits extreme hardness for long head life. yet sendust has drawbacks that disqualify it from use throughout the head. Two characteristics important for high-frequency response, specific resistance and permeability, are quite low. And permeability is lower still when metal alloys are added to offset sendust's tendency to rust.  Sony has produced a corrosion-resistant sendust formulation without sacrificing permeability. And Sony has applied sendust only where its draw backs are less important, and its maximum flux density is most impotrant; at the tip of the head, surrounding the gap. The majority of the magnetic core is composed of ferrite, a material with high specific resistance and high permeability, for extended high-frequency response. Thus, the Sendust and Ferrite head combines all the performance advantages of both ferrite and sendust without the disadvantages of either.



 It is often overlooked that the head's mechanical construction is just as important  as its chemical composition. For example, the physical stress on the head core during fabrication can degrade audio performance. Many organic bonding agents used in conventional heads allow slippage over the years, causing the head gaps to spread or "scatter". Left and right channels can be subject to signal phase shift. Also the core of the head can twist and the gap filler can buckle, deforming the critical point of tape-to-head contact. Sony overcomes these problems through careful head design and fabrication,. Inorganic bonding materials are used throughout, for their superior strenght. Qurtz gap filler - applied by vapor deposition - provides an ideal match for Sendust's excellent hardness. And special low-stress manufacturing techniques are used to form and polish the magnetic materials. The result is a head that delivers the full performance of sendust and ferrite, and continues to deliver this performance over many years of use.

LED Peak Program Meters
Recording levels on the K44 can be monitored on bright, sixteen-segment light-emitting diode (LED) Peak Program Meters. Because LEDs have no mechanical inertia to overcome, they can follow the transient peaks of music with outstanding accuracy.  Calibrated across a broad range from -30 to +30 dB, the meters feature an expanded scale in the critical range around 0 dB. Above 0 dB, the LED segments are red, to indicate the onest of potential tape overload. Because the meters are arranged in two parallel lines, you can evaluate left/right channel balance at a glance. Also, with automatic peak-hold, the highest peak indication remains lit for 2,5 seconds, or until a higher peak is established. Automatic peak hold is particulary useful when you first set recording levels.

Additional Features
The K44 has the same complement of convenient controls and operating features as the K22, plus three additions. First is "punch-in" recording, the ability to go from the Play mode directly into the Record mode, without first pressing Stop. Punch-in recording permits more professional results when taping material onto a previously recorded track.  Second, the Record Mute allows you to blank out broadcast commercials and other interruptions, while remaining in the Record mode.  Third, and finally, the K44 incorporates a volume control for manual adjustment of the headphone output levels.



Specifications TC-K44
Fast-Forward/Rewind Time (C-60):  90 sec.
Wow and Flutter:  0,06% (WRMS);  0,17% (DIN 45507)
Frequency Response (-3 to +3 dB, Re: -20 dB):
Metalic Tape : 30 - 15,000 Hz
FeCr Tape : 30 - 15,000 Hz
EHF Tape : 30 - 14,000 Hz
SHF Tape : 30 - 13,000 Hz
Frequency Response at Re 0 dB:
Metallic Tape : 30 - 13,000 Hz
Signal-to-Noise Ratio (Dolby NR Off, Re: 3% THD, Peak, IHF-A weighted):
Metallic Tape : 58 dB
FeCr Tape : 58 dB
EHF Tape : 56 dB
SHF Tape : 52 dB
Improvement with Dolby NR On : Up to 5 dB at 1 kHz, 10 dB at 5 kHz or Above
Total Harmonic Distortion (1 kHz, Re: 0 dB Record Level):
Metallic Tape : 1,0%
FeCr Tape : 1,0%
Crosstalk (1 kHz, tracks):  60 dB
Separation (1 kHz, channels):  35 dB
Erasure (400 Hz, incl. Mettallic Tape):  60 dB
Bias Frequency:  105 kHz
Meter Range:  -30 , +8 dB
Line Input Sensitivity/Impedance:  77,5 mV/50 k Ohms
Mic Input Sensitivity/Impedance:  0,25 mV/Low
Line Output: Level, Fixed:  435 mV
Line Output: Load Impedance, Nominal:  50 k Ohms
Load Impedance, Minimum:  10 k Ohms
Headphone Output Level:  0 - 77,5 mV
Nominal Headphone Impedance :  8 Ohms
Power Requirements:  AC 120 V, 60 Hz
Power Consumption: 14 W max
Dimensions (W x H x D):  430 x 105 x 290 mm (17" x 4-1/8" x 11-3/8")
Weight:  5,0 kg (11 lbs) 


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