Luxman T-4 / T-4B (1978–1980)

Name: Luxman T-4
Brand: Luxman

That rare tuner that doesn’t just find stations—it holds them, locks them, and makes you forget you’re listening to radio at all.

Overview

The Luxman T-4 is a serious AM/FM stereo tuner. It was built between October 1978 and 1980 as part of Luxman's "Ultimate High Fidelity Stereo Component" series, a lineup aimed at no-compromise performance during Japan's golden era of analog audio. It came in two color variants: the silver T-4 and the black T-4B. Both share the same internal design. It was priced at ¥58,500 at launch (about $247.50 at the time). That wasn't cheap, but it wasn't meant to be disposable either.

The T-4 is about how it behaves, not only its specs. It grabs a station and keeps it, thanks to Luxman's proprietary CLL (Closed Loop Locked) system, which synchronizes the front end, IF stage, and detector using a crystal-controlled reference. No drifting, no hunting. When you land on a frequency, the Accu-touch mechanism gives a subtle mechanical click and locks the knob in place for about a second so you know you've hit the spot. It's a tactile detail that feels almost obsessive.

It was built by SONIC, a contractor that also manufactured other respected Luxman models like the T-12 and T-50A. It isn't as legendary as the T-110, T-12, or T-510, and it has been called "the best of the rest" among Luxman's analog tuners. That makes it a solid-tier performer with top-tier engineering.

Specifications

Manufacturer	Luxman
Model	T-4 / T-4B
Production years	October 1978 - 1980
Original price	¥58,500
Product type	AM/FM stereo tuner
Practical sensitivity (FM, IHF)	1.8 μV / 10.3 dBf
50 dB quieting sensitivity (FM)	3.3 μV / 15.6 dBf
Signal-to-noise ratio (FM)	75dB
Frequency characteristic (FM)	30 Hz to 15 kHz ± 0.5 dB; 50 Hz to 10 kHz ± 0.3 dB
Distortion factor (FM, wide)	mono: 0.07%(100Hz), 0.07%(1kHz), 0.15%(6kHz); stereo: 0.15%(100Hz), 0.1%(1kHz), 0.25%(6kHz)
Distortion factor (FM, narrow)	mono: 0.2%(1kHz); stereo: 0.5%(1kHz)
Capture ratio (FM)	wide: 0.9dB; narrow: 1.8dB
2 signal selectivity (± 400 kHz)	wide: 40dB; narrow: 80dB
Spurious characteristic	80dB
IF interference rejection ratio	80dB
Image ratio (FM)	55dB
Amplitude modulation suppression	60dB
Stereo separation (FM)	wide: 45dB(100Hz), 50dB(1kHz), 40dB(10kHz); narrow: 30dB(1kHz)
Carrier leak rejection ratio	65dB
Output Voltage / Impedance (FM)	1V/100 Ω
Muting threshold (FM)	10 μV ~ 300 μV
Practical sensitivity (AM, IHF)	250 μV/m
Image ratio (AM)	50dB
IF interference rejection ratio (AM)	40dB
Signal-to-noise ratio (AM)	50dB
Distortion factor (AM)	0.6%
Output voltage (AM)	0.3V
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	8W
External dimensions	Width 438 x Height 84 x Depth 346 mm
Weight	6.5kg

Key Features

CLL (Closed Loop Locked) Tuning System

The CLL system is the core of the T-4's performance. Conventional tuners rely on manual alignment or basic PLL circuits. CLL uses a crystal oscillator to control the transmission frequency reference, locking the entire signal path - front end, IF stage and detector - into precise synchronization. This eliminates drift and greatly improves stability, especially in weak signal areas.

Accu-Touch Tuning Mechanism

When you stop turning the knob at the exact center of a station, the Accu-touch system engages. It uses the control voltage from the CLL circuit to detect the peak signal point, then mechanically locks the tuning knob in place for about one second. The "click" is functional as well as satisfying. It tells you without looking at the meter that the tuning is right.

RF and IF Stage Design

The RF stage uses a MOS-type FET, chosen for its low noise and high input resistance. That suits pulling in weak signals without adding hiss. The IF stage has switchable bandwidth (wide/narrow). Wide mode uses two sets of ceramic filters optimized for group delay characteristics. Narrow mode adds a narrow band ceramic filter. The dual-filter approach lets you trade bandwidth for better selectivity in crowded band conditions.

MPX and Audio Stages

The MPX (stereo demodulator) stage uses carefully selected PLL-ICs for accurate stereo decoding. A 3-pole low-pass filter works independently on left and right channels, which reduces crosstalk and improves high-frequency clarity. The audio stage uses an operational amplifier IC, contributing to low distortion and clean output. A beat prevention circuit is also included to eliminate heterodyne interference, a common annoyance in urban environments.

Front Panel and Indicators

The T-4 has a 5-level signal strength indicator and a center indicator to assist with tuning. It also has an FM muting switch and a muting level control, so you can adjust when the audio cuts out during weak reception. These are real tools for fringe areas.

Historical Context

The T-4 arrived in 1978 as part of Luxman's push into the high-end tuner market with precision-engineered, no-compromise components. Built by contractor SONIC, it shared manufacturing with other respected models like the T-12 and T-50A. It wasn't the flagship - the T-110 and T-510 held that spot - but it was designed to deliver flagship-level engineering at a more accessible point in the lineup. It was intended to pair with contemporary components like the L-4 amplifier, for audiophiles who valued stability, clarity, and build quality over flash.

Collectibility & Value

The Luxman T-4 is not extremely rare, but it's not common either. Used prices vary widely. One listing in 2024 showed a unit for $250, with a note that others have sold for up to $500. Forum reports suggest a more typical range of $75 - $100 for functional units, so condition and provenance play a big role. A unit described as working fine but with "some deep scratches on top edge of front panel" sold for $250, so cosmetic flaws don't always kill value if the electronics are intact.

One common maintenance item mentioned by owners is dial light replacement. It's a minor issue. No widespread failure modes are documented in the available sources, though at this age the capacitors, switches, and potentiometers could eventually need attention. Given its solid construction and lack of active gain stages in critical paths, the T-4 is likely to survive in good working order if not abused.

Market Value

┌──────────────────────────────────────────────────────────────────────────┐
│ LUXMAN T-4                                                      Jul 2026 │
├──────────────────────────────────────────────────────────────────────────┤
│ High      $256                                    Latest             $55 │
│ Median    $46                                     Trend             ▲ Up │
│ Low       $23                                     Volume          ~10/mo │
├──────────────────────────────────────────────────────────────────────────┤
│   $300 ┤                                                                 │
│        │                                                                 │
│        │                                             .                  .│
│   $171 ┤                                          .                      │
│        │               .                    .     .                      │
│        │                .   .                                            │
│        │          .     .      .      .           . .                  . │
│     $0 ┤. .          .         .. ... .        .   .                  .  │
│        ├─────────────────────────────────────────────────────────────────│
│    vol │▂ ▂       ▅  ▂ ▂█   ▂  ▅▂ ▂▂▂ ▅     ▂  ▂  █▂▂▂                ▂▂▂│
│        └─────────────────────────────────────────────────────────────────│
│         2026-05                      2026-06                      2026-07│
└──────────────────────────────────────────────────────────────────────────┘