Teac V-680 (1989–1991)

Name: Teac V-680
Brand: Teac

At 5.8kg, it sits in the rack heavy. This isn't another plastic-cased cassette deck built to fade. It's a precision instrument built to last.

Overview

The Teac V-680 is a high-end stereo cassette deck produced from 1989 to 1991, near the end of analog tape's best years and before digital took over. Teac marketed it to audiophiles and semi-professional users. It stands out in the lineup for its rigorous engineering, three-head configuration, and comprehensive noise reduction suite. It cost ¥59,800 around 1989, and it was aimed at listeners who wanted transparency, control, and tape performance that could rival open-reel systems in critical listening. It was made in Japan and finished in black with standard wood side panels. The weight and construction make the intent obvious before the first tape goes in.

The deck measures 471 mm wide, 122 mm high, and 275 mm deep. That is a typical footprint for a high-end two-box mechanism of the era, but the 5.8kg mass shows a chassis built for stability. It has a heavy zinc die-cast head base, a sintered alloy flywheel on the capstan, and a cabinet twice as heavy as conventional designs. All of it aims at the same thing: less vibration, better tape-to-head contact, and a clean signal. It wasn't Teac's first try at high-fidelity tape, but with the V-680 the company consolidated decades of refinement into one focused machine.

Three-Head Configuration with Permalloy Elements

The V-680 uses a true three-head system with separate record, playback, and erase heads. Each is made from high-hardness permalloy and mounted in an ultra-precision zinc die-cast base. This allows independent optimization: a wide-gap recording head for broad frequency capture, and a narrow-gap playback head for extended high-frequency response. The heads are positioned by precise calculation to keep contact uniform even when tape pad alignment varies slightly. That is a subtle detail, but it matters for consistent azimuth and high-frequency retention. Because the playback head isn't used for recording, users can monitor in real time off the tape. The entire head block is isolated within a rigid structure, which minimizes microphonic effects and keeps alignment stable over the long term.

DC Servo Capstan with Sintered Alloy Flywheel

Tape speed accuracy depends on the capstan drive. The V-680 uses a DC servo motor with a capstan of extremely high roundness, under electronic control, to keep speed deviation minimal. A heavy-weight flywheel made of sintered alloy is built into the capstan assembly. It adds inertial mass and smooths out motor ripple. Wow and flutter is rated at just 0.045% WRMS (±0.07% Wpeak, EIAJ), a figure competitive with the best cassette decks of its time. That keeps pitch locked, even during complex transients.

All-DC Amplifier with Capacitor-Free Signal Path

One of the V-680's most significant design choices is its all-DC amplifier configuration, which eliminates coupling capacitors between the head and the preamp. The playback head connects directly to the amplifier stage, so the deck avoids the phase shifts and low-frequency distortion common in AC-coupled designs. Most of the amplifier circuitry, from input to output, sits on a single board. That shortens the signal path and keeps noise out. The system also uses a ±2 power supply with completely separate supplies for the amplifier, mechanism, and noise reduction sections, which gives a clean ground potential and reduces crosstalk. High-quality aluminum electrolytic capacitors, designed for digital audio applications, are used where necessary.

Dolby HX Pro and B/C Noise Reduction

The V-680 has Dolby HX Pro, a recording bias optimization system that dynamically adjusts headroom during recording to prevent high-frequency saturation, particularly on metal and chrome tapes. That gives cleaner, more detailed recordings without manual bias tweaking. For playback, the deck supports both Dolby B and Dolby C noise reduction. With Dolby C engaged it offers up to 80 dB of signal-to-noise ratio (1 kHz or higher). With Dolby B, the S/N ratio reaches 70 dB (5 kHz or higher), and 60 dB without noise reduction. The deck handles normal, chrome, and metal tapes, and the built-in auto tape selector detects each type automatically.

Frequency Response Across Tape Types

Frequency response depends on the tape formulation, and it pushes the limits of the cassette format. With metal tape, the V-680 reaches a full 20 Hz to 21 kHz. Chrome tapes yield 20 Hz to 20 kHz, and normal (ferric) tapes reach 20 Hz to 18 kHz. These ranges, combined with the narrow-gap playback head and all-DC signal path, give a sound that is open and detailed. The deck's ability to resolve high-frequency detail without harshness is particularly notable.

Microprocessor-Controlled FL Display and Remote Operation

The V-680 has an FL (fluorescent) multi-function display under microprocessor control. It shows the tape counter, mode settings, and operational status. The 2-mode electronic counter can display either traditional tape position or elapsed run time, which helps with cueing and editing. A wireless remote control is included, allowing full operation from a distance - a rare feature at this level. The remote handles functions like auto-rec mute, which inserts a brief unrecorded gap of about four seconds, useful for track separation. The auto-monitor function automatically switches monitoring between source and tape during record and playback.

Advanced Tape Transport and Cabinet Design

Beyond the capstan, the transport uses a DC motor for the reel servos, which gives smooth winding with minimal vibration. The cassette lid is made from high-rigidity hard resin to resist flex and dampen resonance. Inside, the cabinet has a unique vibration control design: the top panel uses a sandwich structure with steel plates suspended on cushioning materials, which greatly increases damping. Combined with the doubled cabinet weight and large insulators, that makes a highly inert platform. The back tension (tape tension) is also reduced by design, which lowers stress on the tape and improves running characteristics over long playback sessions.

Input/Output and Operational Flexibility

The V-680 has a line input sensitivity of 87mV with an impedance of 50kΩ or higher, suitable for most preamplifiers and sources of the era. The line output delivers 0.43V, also into 50kΩ or higher. A headphone output is available at 8Ω, though no dedicated amplifier specs are documented. The deck includes an MPX filter switch, needed for clean FM recording because it removes the 19kHz pilot tone. Bias fine tuning is adjustable within ±20%, so users can optimize recording levels for specific tape brands. The preset master volume uses double control for fine adjustment.

Collectibility & Value

Owners report the V-680 sounds good, with one Tapeheads.net user noting, “I also own Teac V-680 and it sounds quite good.” A Facebook Marketplace listing describes it as a “high-end vintage TEAC V-680 cassette deck in mint condition,” and calls it a “true 3-head, two motors deck designed for audiophiles and studio-grade recordings.” HiFI-Stereo (1991, p.123) noted its frequency response of 20-20,000 Hz with chrome tape and a wow and flutter of 0.045%(WRMS) ± 0.07% (Wpeak, EIAJ). No current market prices are documented, and there is no information on common failures or parts availability.