Accuphase T-108 (1990–1993)

Name: Accuphase T-108
Brand: Accuphase

Accuphase built the T-108 when it decided a tuner could be a flagship component in its own right. It came out in Japan in April 1990 at ¥120,000. It was a quartz-synthesizer FM stereo tuner at the top of the company's tuner line, and it succeeded the T-107. Per the surviving documentation, it is the only Accuphase tuner designed to cosmetically match the rest of the series with natural persimmon wood side panels.

The tuning system is the interesting part. Accuphase called it pulse tuning. A traditional rotary knob generates pulses through a radial slit on its shaft, and the tuning frequency is set by counting those pulses against a crystal oscillator. You tune by hand, but you get quartz accuracy and none of the drift or vibration sensitivity of a conventional analog front end. There is also a 16-station random-access memory, and each preset can carry its own filter and sensitivity settings. That helps when a weak station needs the Narrow IF mode to fight adjacent-channel interference. The German-language owner's manual confirms the 16-station memory and notes that bandwidth and filter can be switched per preset depending on reception conditions.

The front end uses double-tuned input and amplifier stages. Frequency conversion is done by a differential-FET balanced modulator with a balun transformer, and a PIN diode attenuator handles strong local signals without overload. Detection is Accuphase's DGL (differential gain linear) method, with nineteen high-speed logic ICs in series delaying phase by 114 degrees, paired with a group-delay-flat IF filter. The stereo demodulator is a PLL locked to the pilot signal, using a ceramic resonator and a variable reactance circuit. Accuphase's own literature claims this arrangement needs no adjustment and holds separation steady against temperature and line-voltage drift. Two IF filters, Normal and Narrow, are switchable.

Two details stand out for a tuner of this era. First, the T-108 was the first Accuphase tuner to offer a balanced output - an XLR stage at 200 Ω, alongside the usual fixed and variable RCA outputs (200 Ω and 1.25 kΩ max respectively). Second, it shipped with a remote control, the RC-6, which could also drive the E-405 integrated amplifier and DP-60 CD player. The manual lists the RC-6 as an optional accessory rather than standard, though period listings suggest most examples were sold with one. The front panel is the traditional Accuphase champagne gold hairline finish. The display is a fluorescent digital frequency readout with a switchable signal-strength/multipath meter.

Published specs, from the single source that documented them fully: 76.1–89.9 MHz tuning range, 11 dBf practical sensitivity (IHF), 17 dBf for 50 dB S/N in mono and 37 dBf in stereo, 90 dB mono S/N and 85 dB stereo S/N at 80 dBf with A-weighting, 0.02% mono THD at 1 kHz and 0.04% stereo, capture ratio 1.5 dB, image rejection 100 dB, and a frequency response of 10 Hz–16 kHz, +0/−1.0 dB. Power consumption is 15 W, weight 9.4 kg, dimensions 475 × 115 × 351 mm. Accuphase rated it for 100/117/220/240 V at 50 or 60 Hz.

Production ran from 1990 to 1993. The T-108 is fairly rare on the second-hand market. Well-preserved examples with the remote tend to command around €1,000, and functional units list between roughly $575 and $1,190 depending on condition and completeness. Replacement lamps are available cheaply. Beyond that, almost nothing is documented - no common failure notes, no repair procedures, no service manual links have surfaced. If you own one and have documentation, the Archive would welcome it.

Known Specifications

Type: Quartz-synthesizer FM stereo tuner
Released: April 1990 (Japan), ¥120,000
Production: 1990–1993
Tuning range: 76.1–89.9 MHz
Tuning system: Quartz synthesizer with pulse-tuning rotary knob; 16-station random memory
Detection: DGL (differential gain linear) method
IF filters: Normal and Narrow, switchable
Outputs: Balanced XLR (200 Ω), fixed RCA (200 Ω), variable RCA (1.25 kΩ max)
Output voltage: 1.0 V (±75 kHz deviation)
Sensitivity (IHF): 11 dBf practical; 17 dBf mono / 37 dBf stereo for 50 dB S/N
S/N (80 dBf, A-weighted): 90 dB mono, 85 dB stereo
THD: 0.02% mono, 0.04% stereo (1 kHz, 80 dBf)
Frequency response: 10 Hz–16 kHz, +0/−1.0 dB
Capture ratio: 1.5 dB
Dimensions: 475 × 115 × 351 mm
Weight: 9.4 kg
Power: AC 100/117/220/240 V, 50/60 Hz; 15 W consumption
Remote: RC-6 (also operates E-405 and DP-60)
Finish: Champagne gold hairline, natural persimmon wood side panels