Audio Database

ATC-1
Commentary

A preamplifier designed in pursuit of the shape of a preamplifier that is currently required.

A 3-stage K-K NF system, which is used in the Marantz Model7, is used for the Ixerair circuit.
A β circuit driven with low impedance reduces distortion over the entire bandwidth.

Equipped with an equalizer output terminal.
This jack does not pass through switches or volumes from input to output, so you can enjoy the sound of the 3-stage K-K NF equalizer.

The line amplifier circuit has a simple circuit structure. The tone adjustment circuit such as tone control and filter is removed, and the cathode follower is added after the first stage amplification.

A fast recovery diode is used for the high-voltage B power supply circuit of the power supply section.
In addition, by adopting a strict CR filter circuit and constant voltage circuit for the heater power supply, the obstacle of hum noise from the heater circuit is eliminated.

In the chassis configuration, the power supply section, line section and equalizer section are separated by copper-plated shield plates, and the volume switches are shielded by aluminum plates to separate the amplification of sections with different signal levels and eliminate mutual interference.

The chassis consists of a 1.6 mm thick welded box-type heavy chassis and aluminum and copper plated shield plates to provide a vibration-proof structure with high rigidity and non-magnetism.

The circuit mounting eliminates the influence on sound by eliminating printed wiring.
All terminals are caulked on glass epoxy boards, and the manual wiring method is adopted one by one.

The front panel is made of 8 mm thick extruded aluminum with anodized processing. In addition, the knob and nameplate are made of solid aluminum with anodized processing.
It uses 1.6 mm steel chassis for the chassis and 2 mm thick aluminum plate for the top plate, and has 4 levels of metallic paint.

Model Rating
Type Control amplifier
Output voltage Rating : 2 v
Maximum : 15 v or more
Output impedance Pre out, EQ out : 600 Ω
Total Harmonic Distortion Factor (2 v, 1 kHz) Phono : 0.05% or less
Line : ≤ 0.02%
Input impedance Phono : 47k Ω
Line : 100k Ω
Vacuum tube used 12AX7/ECC83x5
External dimensions Width 430x Height 90x Depth 325 mm
Weight Approx. 7 kg