We aim to manufacture best amps to experience music. The sound full of "musicality" faithfully reproduces the artistry of the performer.

The amplifier is a musical instrument

The most important concept of SPEC is "the amplifier is a musical instrument".

The wooden panels integrated with the amplifier provides beautiful and natural tones in the music. The bottom panel is made of thick SPRUCE wood, which is the same material used as the front panel of a violin. The side panels are made of MAPLE wood, similar to backside of a violin. They vibrate with music and enhance the beautiful natural tones.

Like a musical instrument maker, we carefully selected materials and considered different combinations.

Only Hickory supports the full weight of the main chassis

Wooden feet of maple wood with hickory embedded in the center are designed in such a way that only the hickory located in the center is grounded.
The RPA-MG1000 is built as an instrument.

Tone color expression is expression of texture.

The sounds of instruments and human voice contain an enormous amount of detailed harmonic signals, which form a beautiful sound. The PURE DIRECT SYSTEM of RPA-MG1000 amplifies all these minute signals faithfully without exception.

The sounds of violins contain a lot of detailed harmonics.



Complex and miniscule harmonic overtones result in beautiful audio

SPEC takes special concern in the faithful representation of minute audio signals

Stereophonics to express space of three-dimensional sound.

Stereophonics represent a stereo image of sound with a slight difference between the left and right signals.

With the reliable reproduction of minute signals, we can feel realistically a three-dimensional effect.

SPEC takes special concern in the faithful representation of minute audio signals

The leading role in musical expression is a minute signal.

SPEC delivers "music" to you in a system that does not compromise on minute signals.


Direct connection at source device level.
Conventional, pre-amplifier-based connections are small level connections. For small signals, transmission at a large level is advantageous because, the small signal in the small level signal shrinks further and could disappear completely.


Amplifies almost all minute signals with analog attenuator and analog PWM.


The CLASS D POWER STAGE absorbs the Counter electromotive force and drives the speakers accurately to a minute signal.

The SPEC system amplifies the “amplitude” by analog processing,
so it can be accurately called an analog amplifier.

Large sized R-CORE TRANSFORMER supplies
a large volume of power

Powerful energy drives the speakers reliably, reproducing the sound pressure of the instrument. Sound pressure is the energy of the instrument itself.

A pair of small FETs amplifies the music signal directly.

Very small FETs by Infineon Technologies amplify audio signals up to 300W amplitude. Simple and small circuit enables the sound with high-speed and highly clear tone. This is possible due to FETs almost completely preventing heat generation. There is no huge heat sink. Only a small heat sink is on the board.


1 Neutral: very close to the actual sound of the instruments
2 Sophisticated: Artistic quality beyond the actual sound

It is a quite different method from that of a conventional tone control. Frequency characteristic does not change at all. Each mode is depending on the adopted parts itself.

But isn't that a job for a pre-amplifier? ..No! The class D circuit has a very sensitive point. At the post-stage of CLASS-D, musicality change can be achieved very effectively. We don’t change frequency characteristic, we merely change resonance characteristics of special parts at the post-stage of CLASS D.

Capacitors for musicality

Side panel for the sound (MAPLE)

RPA-MG1000 appearance




Maximum output 300 W × 2 (4Ω), 150 W × 2 (8Ω)
Speaker Impedance 4Ω-16Ω
Frequency response 10 Hz - 30 kHz ±1dB
Line input terminals XLR input: 1 RCA inputs:1
Speaker terminal NO.1,NO2
Power voltage 230V AC, 50 Hz/60Hz
External dimensions
450 mm (width) × 180 mm (height) × 430 mm (depth)
External dimensions
450 mm (width) × 180 mm (height) × 455 mm (depth)
Weight (POWER UNIT) 27 kg
Weight (AMP.UNIT) 18 kg

Operation Manual

Related products

Volume controller for PURE DIRECT CONNECTION

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