Audio Database

Image of A-913
Commentary

This pre-main amplifier was developed by refining the model sold overseas with the concept of how to express music without relying only on excessive high power and numbers.

The power amplifier circuit is composed of discrete elements to ensure freedom in sound quality design.
A feedback type constant current differential amplifier stage is adopted for the input of the power section to provide stable operation, and a linear switching circuit is adopted for the output stage to improve the linearity of circuit operation without changing bias and to suppress crossover distortion.

The power supply section is composed of a large transformer and an electrolytic capacitor (10,000 μ Fx2) in an orthodox way. The diode is a bridge type with four large current types in one package.

Each block is arranged so that the signal path from the input pin jack is the shortest in order to ensure simplicity and straightness.
In addition, it is equipped with all source direct switch that all sources including CD are directly input to the power amplifier via the exclusive volume only.

For the insulator, we have adopted a vibration prevention structure with improved thickness in the middle and low range by using a special structure of pinpoint receiver.

It comes with a remote control and you can operate the tuner T-403 as a pair.
In addition, in order to prevent digital noise from mixing in, we have adopted a special power supply for the microcomputer. In addition, a microcomputer block for the remote control is placed between the front angle and the front panel for magnetic shielding.

Model Rating
Type Stereo pre-main amplifier
Rated output
(20 Hz to 20 kHz, CD → SP out, both channels driven)
75W + 75W (6 Ω)
60W + 60W (8 Ω)
Dynamic Power 2 Ω : 135W + 135W
4 Ω : 110W + 110W
6 Ω : 95W + 95W
Total harmonic distortion rate (20 Hz to 20 kHz) 0.08% (CD → SP Out, at rated output, 8 Ω)
0.003% (Phono MM → Rec Out at 3 v output)
0.015% (Phono MC → Rec Out at 3 v output)
Intermodulation distortion factor (20 Hz to 20 kHz) 0.06% (CD → SP Out, at rated output)
Powerbandwidth 5 Hz to 100 kHz (IHF-3dB, THD 0.2%, 8 Ω)
Damping factor 40 (1 kHz, 8 Ω)
Frequency characteristic Phono → Rec Out (RIAA deviation) : 20 Hz to 20 kHz ± 0.5 dB
CD → SP Out : 2 Hz ~ 80 kHz + 0 -3dB
Phono maximum allowable input
(1kHz/10kHz, 0.005%)
MM:150mV/710mV
MC:20mV/110mV(0.08%)
Input Sensitivity / Impedance Phono MM : 2.5mV/50k Ω
Phono MC : 350 μ V/330 Ω
CD, Tape Play, etc. : 150mV/50k Ω
Rated output voltage / impedance Tape Rec, etc. : 150mV/3k Ω
SN ratio (IHF-A filter input short) Phono MM:83dB
Phono MC:65dB
CD, other : 97 dB
Tone Control Maximum Change Bass : ± 10 dB (20 Hz)
Treble : ± 10 dB (20 kHz)
Muting -20dB
Pwer 100 VAC, 50Hz/60Hz
AC outlet Switched : 2 systems, 100W
Unswitched : 1 line, 100W total
Power consumption (Electrical Appliance and Material Control Law standard) 115W
External dimensions Width 455x Height 120x Depth 330 mm
Weight 6.7kg
Attachment Remote control