TEAC A-250

Commentary

This is a stereo cassette deck with a built-in Dolby system which is a sister aircraft of the A-350.

The Dolby System automatically raises the recording level by extracting only mid - and high-range Pianissimo.
On the other hand, the level of the medium - and high-frequency components is reduced during playback, thereby reducing the tape hiss by the level difference.
The B type of the Dolby System, which is used in the A-250, improves SN by compressing and expanding only medium and higher tones, which contain a lot of tape hiss and transistor noise components, and suppresses noise from the tape hiss and the transistors on the deck.

The head uses HD (high density) ferrite head, which is harder than the conventional permalloy head, so it has excellent abrasion resistance and long life.
In addition, the gap, which has the most influence on the head characteristics, is processed with high precision using ultra-precision grinding equipment to improve linearity and minimize phase difference.
In addition, not only the core part that the tape touches but also other parts are covered with ferrite. The mirror surface finish prevents dust from sticking to the tape. Combined with the unique hyperbolic curve, excellent head touch is realized.

The motor uses a hysteresis synchronous outer rotor motor developed for the cassette.
Since the rotor (rotor) rotates outside the stator, the outer rotor motor has features such as less uneven rotation due to the flywheel effect, less leakage flux and less heat generation, and stronger starting torque.

Equipped with a tape selector, by switching the switch, it is possible to record utilizing the characteristics of both general tape and chrome tape.

Instead of the conventional line input, which is attenuated by simply using a resistor, it is equipped with an independent circuit that can switch between the microphone input and the line input, thereby improving the SN ratio of the recording amplifier by more than 15 dB.

Equipped with an expanded scale VU meter, it can monitor up to approximately + 6 VU at full scale.

Equipped with a tape running indicator lamp.

Equipped with a slide volume that can be adjusted independently on the left and right when recording.

Equipped with a headphone terminal with a dedicated amplifier.

Equipped with 3-digit index counter.

Model Rating

Type	Stereo cassette deck
Track format	4-track, 2-channel stereo system
Tape used	C-60, C-90 Type
Tape speed	4.8cm/s
Motor	Hysteresis synchronous outer rotor motor
Wow and flutter	0.15%
Early winding time	Up to 90 seconds (C-60 tape)
Frequency characteristic	30 Hz ~ 16 kHz (Chrome Tape) 30 Hz ~ 13 kHz (Normal Tape)
Signal-to-noise ratio	NR Out:50dB Dolby In:58dB
Input Sensitivity / Impedance	Line : 0.1V/50k Ω or more Microphone : 0.25mV/-72dB/600 Ω ~ 10k Ω
Output Level / Impedance	Line : 0.3V/10k Ω or more Headphone : 8 Ω
Pwer	100 VAC, 50Hz/60Hz
Power consumption	16W
External dimensions	Width 423x Height 103x Depth 250 mm
Weight	4.5kg