Pre-main amplifier equipped with 105 series SEA system.
This is the first pre-main amplifier equipped with a 7-element SEA system.
The SEA system makes it possible to adjust the frequency within a fine range and adjust the
sound field, program source and component balance according to the listening room. It is also
equipped with a center frequency switching function of 40 Hz and 60 Hz to increase the bass
sound.
The the SEA linear volume, a center stopper type is adopted so that the SEA knob becomes flat
at the center, and the SEA circuit is a 2-stage direct-coupled NF type to realize low distortion
factor.
This is the first audio amplifier equipped with a pink noise generator.
You can use this function to check the phase of connected speakers, adjust the level of multi-
channel playback, and adjust the level of multi-amplifier playback.
Darlington complimentary service SEPP-OTL circuit is used for the power amplifier section.
An electronic automatic recovery circuit is mounted as a protection circuit to protect the power
transistor.
The equalizer is a 3-stage direct connection type using a selected low-noise silicon
transistor 2SC458LGC.
In the 3-stage type, the gain of the circuit can be large, and since the NF can be taken
deep even in the high frequency range, the distortion can be suppressed over the whole range,
and the dynamic range can be wide.
The Aux1 connector has a level control at the input.
The pre-out1 and power amplifier input terminals also have a level adjustment volume.
This volume can be used to improve the S/N ratio when the efficiency of the combined
speaker system is high and residual noise is reduced.
It is equipped with functions such as audio muting, mode selector and SEA ON-OFF
switch.
There was a wood case as an option sold separately.
Model Rating
Type Pre-main amplifier
Power Amplifier Unit
Music Power (IHF) 100W total (4 Ω)
80W Total (8 Ω)
Effective power 36W + 36W (4 Ω)
32W + 32W (8 Ω)
Harmonic distortion factor (1 kHz) 0.07% (at 30W output)
Cross modulation distortion factor 0.2% (at 30W output, 60 Hz : 7 kHz = 4 : 1)
Power band wiz 20 Hz to 50 kHz ± 0.5 dB
Frequency characteristic 18 Hz to 100 kHz
* Built-in subsonic filter
S/N(IHF) 100dB
Residual noise voltage 0.5mV
Subsonic filter 18Hz:-3dB
-12dB/oct
Input Sensitivity / Impedance 0.6V/50k Ω (With Level VR)
Load impedance 4 Ω ~ 16 Ω
Damping factor 50 (Load 8 Ω)
Headphone port 8 Ω
Speaker switching A, B, A + B
Protection circuit Electronic
Preamplifier Section
Input terminal Phono1, 2, Mic, Tuner, Aux1 (with level VR), 2, Tape play
Input Sensitivity / Impedance Phono : 1mV/50k Ω
Mic : 1mV/300k Ω
DIN : 80mV/100k Ω
Aux, Tuner, Tape play : 80mV/100k Ω
Phono maximum allowable input 120mV
Output terminal Pre out1 (with level VR), 2
Rec out1 (linked with DIN), 2
DIN terminal Route 2
Output impedance Pre-out1 : maximum 2.5 V, rated 0.5V/3k Ω
Rec out2 : 4.7k Ω
DIN : 36mV/80k Ω
Frequency characteristic Phono : ± 0.5 dB relative to RIAA curve
Aux : 18 Hz ~ 40 kHz + 0 -0.5 dB (Subsonic Filter)
Harmonic distortion factor (1 kHz) 2.5V(0.1%)
Intermodulation distortion factor (1 kHz) 2.5V(0.2%)
S/N(IHF) Phono:76dB
Mic:78dB
Aux:85dB
Tone control SEA7 device (40/60Hz, 150 Hz, 400 Hz, 1k, 2.4k, 6k, 15 kHz)
Each ± 10 dB
Variable Method : Continuous
Equipped with tone defeat switch
Muting -20dB
Tape monitor Route 2
Pink noise generator Mounted
Ground terminal Mounted
<General>
Semiconductor used Transistor : 28
Diode : 8 pcs
Power outlet Interlocking : 2 systems
Non-linked : 1 system
* Total 300W
Pwer 100 VAC (120V/220V/240V Switchable), 50Hz/60Hz
Power consumption No signal : 20W
Maximum output : 145W
External dimensions Width 450x Height 138x Depth 322 mm
Weight 11.5kg
Sold Separately Wooden Amplifier Case WAC-2 (¥ 5,500)