Nakamichi Amplifier1

Commentary

This is an integrated amplifier with a focus on sound quality, with harmonic time alignment technology at the core.

The Harmonic Time Alignment Theory was developed by Steve Kalison of the Nakamichi US Research Center as a result of many years of research focusing on the characteristics of NFB itself. It directly addresses the timing of the fundamental sound and the distortion component and the action of NFB.
The Amplifier1 uses a newly developed amplifier circuit based on this theory for both the preamplifier and power amplifier sections. This circuit uses a wide-band, low-gain open-loop design to keep the amount of NFB in the audio band constant and to minimize the amount of NFB itself. This circuit combines techniques to correctly adjust the phases of the fundamental sound and distortion components over the entire audio band.

The line amplifier section is composed of discrete elements so that high-quality sound devices can be installed.
As a result, high-quality parts which cannot be used in IC configuration can be used everywhere, and the frequency characteristics of the open-loop gain can be kept constant.
We also use a main volume driven by a motor drive, a motor drive rotary selector, and an electrolytic capacitor with an emphasis on sound quality.

The power amplifier section uses a total of 8 transistors with 2 parallel drives, and has a current supply capability of peak current 28A.

It uses a multi-regulated power supply system to prevent interference between sections and stages around the power supply. The Amplifier1 in particular has separate transformer windings for the preamp section, power amplifier section and control section, and separate local regulators for the equalizer amplifier and line amplifier.
The ground circuit also uses Nakamichi's original isolated ground system to reduce noise interference to the signal system.

Equipped with a high-gain equalizer amplifier with a transistor differential input.

Equipped with CD direct input, signal input from here jumps selector and balance volume, and simple signal transmission is possible by passing through dedicated 4-connected volume.

Equipped with tone control and muting circuit.

It comes with a remote control that can adjust volume, switch input, and operate Nakamichi CD player and deck.

The following are sold separately : signal converter RC-4 used for system remote connection between Amplifier series and remote control deck such as CR-70/CR-50/CR-40/CR-30/CR-20/DRAGON, SRC-2 used for system remote connection between second Casettedeck1/Casettedeck2/Nakamichi1000, and exclusive cable SRC-3 used for system remote connection between Nakamichi1000/1000II/700/700II and Amplifier series.

Model Rating

Type	Integrated amplifier
Power Amplifier Unit
Rated output	80W + 80W (8 Ω, double-channel drive, 20 Hz to 20 kHz, 0.1% THD)
Power bandwidth	10 Hz to 50 kHz
Frequency characteristic	5 Hz ~ 80 kHz + 0 -3dB
S/N days (IHF A-WTD, input short)	105dB
Total harmonic distortion factor	0.1% or Less (8 Ω, Rated Output, 20 Hz to 20 kHz)
Maximum output current	28A peak (per one channel)
Preamplifier Section
Input Sensitivity / Impedance	Phono MM : 2.5mV/47k Ω Phono MC : 0.125mV/100 Ω CD, Tuner, Tape, Aux : 150mV/20k Ω
Total harmonic distortion factor (at 1 kHz, Rec out, 1 V output)	Phono MM : not more than 0.008% Phono MC : not more than 0.01%
RIAA deviation	Phono MM/MC : 30 Hz to 20 kHz ± 0.5 dB
S/N ratio (IHF A-WTD, speaker output)	Phono MM:82dB Phono MC:70dB
Tone control	Bass : ± 10 dB (20 Hz) Treble : ± 10 dB (20 kHz)
<General>
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption	Up to 600W
Power outlet	Switched : 2 systems, up to 200W total
External dimensions	Width 430x Height 125x Depth 360 mm
Weight	Approx. 15.0 kg
Sold Separately	Remote Signal Converter RC-4 System Remote Connecting Cable SRC-2 (¥ 1,200) System Remote Connecting Cable SRC-3 (¥ 1,500)
Attachment : Remote Control Unit Amplifier1 Remote Control
Method	Infrared pulse type
Pwer	DC3V(1.5Vx2)
External dimensions	64 mm wide x 18 mm high x 176 mm deep
Weight	Approx. 140g (Including Battery)