Audio Database

The

LUXMAN L-48A
79,800yen(January, 1980 release)

Description
@
The stereo Integrated Amplifier which adopted the Duo beta circuitry.

The Duo beta circuitry original with a Lux is adopted as equalizer amplifier and power amplifier.
A proper quantity of Duo beta circuitries consist of NFB and a DC servo. First, TIM distortion was reduced by applying a proper quantity of NFB based on the amplifier circuitry with the outstanding nakedness property, and it has contributed to the tone quality of a mid-high range, or reappearance of a feeling of an atmosphere. And in DC servo, the problem of the cross modulation distortion and DC drift by a harmful super-low-pass component was solved, and the braking effect of the speaker excellent in the concurrent has been acquired.

High gain-ization of the equalizer by a Duo beta circuitry is realized, and not only man-month cartridge but MC cartridge is connectable with an equalizer direct.
The circuitry consists of a cascode difference input first rank circuitry with a bootstrap by low-noise FET, and an output stage of Class-A single ended push-pull-circuit adoption, and has composition which was excellent in the nakedness property.
Furthermore, since the high gain of the equalizer itself can be taken, it has succeeded also in banishing the flat amplifier leading to a tone-quality failure.
(Although almost all MC cartridge can connect the Input sensitivity of MC input terminal at 0.3mV, the using of the thing of a high-impedance type as possible is recommended.)

For the output stage, ft (high region cut-off frequency) was selecting carefully and using the large-sized power transistor in which it is high and Cob (collector output capacitance) is low, also accelerated the driver circuitry to it, and has banished switching distortion to it.
Moreover, the newly developed loop type heat pipe is adopted, and the heat-dissipation effect is heightened.

The line straight stream composition is adopted and the faithful transmit is enabled by having the stream composition which linked MC equalizer part and the power amplifier part directly.

The LUX scheme NF type tone control is adopted as a tone control.
Each 2 steps of height region change is possible also for a turnover frequency, and a full it1 is also possible if a defeat location is used.

10 element right-and-left standalone version indicator which displays peek power on real time is carried.
The watt window which can read an output direct is adopted, and when unnecessary, it is also possible to turn OFF with a switchpoint.

Two tapes monitors, a dubbing switchpoint and a Subsonic Filter, and the high cut-off filter are carried.

Rear
Equalizer Loop

Rating of a mode
Form Integrated amplifier
Succession effective output 70W+70W (8 ohms, both channel operation, 20Hz - 20kHz)
THD 0.03% (8ohm, 70W, 20Hz - 20kHz)
Cross modulation distortion 0.03% (8ohm, 70W, 60Hz:7kHz=4:1)
Frequency characteristic Phono man month, MC:20Hz-20kHz}0.3dB
Tuner, AUX: 10Hz - -100kHz one dB
Input sensitivity/impedance Phono man month: 1.2mV/50kohm
Phono MC: 0.3mV/100 ohms
Tuner, AUX:190mV/50kohm
SN ratio (IHF-A) Phono MM:77dB
Phono MC:71dB
Tuner, AUX: 105dB
Subsonic Filter 15Hz, 30Hz
A high cut-off filter 9kHz, 15kHz
AC outlet switched: Two lines
unswitched: One line
Power consumption 250W
Dimensions Width 466x height 145x depth of 333mm
Weight 12kg