TEAC V-680

Commentary

A cassette deck that uses a combination of 3 heads.

The head section uses a combination 3-head system with independent recording and playback, resulting in a wide gap recording head for a wide range and a narrow gap reproducing head for sufficient high-frequency characteristics.
The head is made of high-hardness Permalloy. In addition, the head is shifted to the optimum position based on precise calculation to ensure accurate and uniform head touch even when there is a gap between the head and the crimping position of the cassette tape pad caused by 3 heads, and the back tension (tape tension) is reduced to reduce the load on the tape and improve the running characteristics.
The three integrated recording, playback, and erasing heads are housed in an ultra-precision large zinc die-cast base, providing improved head position accuracy, stable tape travel, and head touch.

The tape drive mechanism uses a high-precision electronic control motor to drive a capstan with extremely high roundness. The capstan is also equipped with a heavy-weight flywheel made of sintered alloy to increase inertial mass and greatly stabilize the driving force to improve tape running characteristics.
The motor is mounted carefully to prevent deterioration of sound quality due to microvibration, and the cassette lid is made of high-rigidity hard resin to minimize vibration, thus minimizing the effect of resonance of the cassette half on sound quality.

In order to reduce the influence of external vibration and sound pressure from speakers, a unique heavy-weight vibration control cabinet is adopted.
On the back side of the top panel, we have adopted a sandwich structure in which steel plates are suspended through cushioning materials. The weight of the cabinet has been increased to twice that of the conventional cabinet, and rigidity and stability have been improved. In addition, the sandwich structure greatly increases the damping effect by mounting the cushion material under pressure, and the sound quality has been obtained by careful tuning of the whole cabinet, which is more effective than the damping material or the simple 2 flexible structure.
In addition, it is equipped with side wood panels as standard equipment to make the cabinet more solid and improve stability and vibration control.

In the past, a coil was used in the resonance circuit of the recording equalizer of the recording amplifier. However, the phase shift that occurs as a high-frequency signal becomes a problem. Taking this into consideration, the TIC has eliminated the coil from the resonance circuit and integrated it into a newly developed linear recording amplifier that realizes accurate localization.

In the amplifier circuit, the power supply to the REC, PB, and NR sections are all separated, and the power supply for the amplifier and the power supply for the mechanism section are completely separated from each other in terms of structure. This prevents interference and noise and reduces sound quality degradation. The ± 2 power supply system makes the ground potential clear, reduces system noise and greatly improves the S / N ratio, as well as transient response characteristics and distortion factor.
In addition, an all-DC configuration is adopted, and by directly connecting the head and amplifier to eliminate the capacitor, distortion factor and phase characteristics in the low-frequency range are greatly improved.

In the circuit section, most parts of the amplifier system from signal input to output are mounted on a single board, and the display section and switches are also directly connected to the board to prevent noise generation and invasion. In addition, the transmission path is shortened naturally by the signal flow to prevent the loss of sound purity.

We use high-quality audio parts such as an aluminum electrolytic capacitor designed for high-quality digital audio.

Equipped with Dolby HX Pro Recording System.
In this circuit, the optimum bias corresponding to the input signal is always applied to the tape to prevent the high-frequency recording capability from being degraded due to the high-level high-frequency signal acting as a bias, and the characteristics in the whole band are also improved.
In addition, fluctuations in the magnetic field of the head and tape when recording high-level high-frequency signals, which cannot be avoided with a fixed bias, and a type of phase shift caused by these fluctuations, thereby greatly improving the orientation.
Since tapes recorded with Dolby HX Pro are different from those recorded with NR, they can be played on decks without Dolby HX Pro.

Equipped with Dolby B/C NR as a noise reduction system.

Equipped with an MPX filter switch.

Equipped with a bias fine tuning function that can be adjusted within ± 20%.

Equipped with Auto-Rec Mute which can make unrecorded part for about 4 seconds.

It uses a preset type master volume, and the level can be finely adjusted by double control.

Equipped with an auto-monitor function that automates the monitor switching between tape and source.

Equipped with an auto tape selector that automatically detects the tape position.

Equipped with 2-mode electronic counter that can display tape counter and tape run.

Equipped with FL multi-function display with microprocessor control.

Large insulator with high damping effect is adopted.

Wireless remote control is included.

Model Rating

Type	Cassette deck
Track format	4-track 2-channel stereo system
Heads	Recording x1 / Playback x1 (Combination Head) Erase x1
Motor	For Capstan : DC Servo Motor For Reel : DC Motor
Wow and flutter	0.045%(WRMS) ± 0.07% (Wpeak, EIAJ)
Frequency response (overall)	Metal : 20 Hz to 21 kHz Chrome : 20 Hz to 20 kHz Normal : 20 Hz to 18 kHz
Signal-to-noise ratio	60 dB (NR off, 3% THD level, WTD) 70 dB (Dolby B NRon, 5 kHz or higher) 80 dB (Dolby C NRon, 1 kHz or higher)
Early winding time	Approximately 85 Seconds (C-60 Tape)
Input	Line : 87mV/50k Ω or more
Output	Line : 0.43V/50k Ω or more Headphone : 8 Ω
Pwer	100 VAC, 50Hz/60Hz
Power consumption	15W
External dimensions	Width 471x Height 122x Depth 275 mm
Weight	5.8kg
Attachment	Wireless Remote Control