Audio Database


Exclusive M7
1,000,000yen(one set, the 1992 release)

Monophonic power amplifier which in addition to the design which supplied the essence of the newest technology polished up the performance so that richer musicality could be reproduced by the repetition of an audition, or craft Manship's prejudice.

The Class-A operation which has neither crossover distortion nor switching distortion theoretically is adopted, and in order to raise the drive capacity at the time of a low load intensity further and to suppress a distorted occurrence, the circuitry which separated the amplifying circuit of a voltage and an electric current clearly is adopted.
The voltage amplification stage adopts the hybrid IC which used the aluminum substrate, and is performing the highly precise voltage amplification using NFB. Moreover, in order that the power amplification stage may secure a power linearity, five-step Darlington and a drive transistor make 2 parallel and a power transistor 6 parallel push pull stream composition, and though it is unreturned amplifier, they make possible current amplification which suppressed the distorted occurrence.
Moreover, it dissociated also in respect of the layout and the voltage amplification stage and the power amplification stage have eliminated the cross interferencee.

In order to prevent the ill effect to the tone quality by RF noises, such as counter-electromotive force generated when the pressure from the outside is applied to the cone paper of a speaker, a radio wave guided to a speaker cable, and a fluorescent lamp,
The voltage amplification stage and the power amplification stage were separated completely, and circuitry without the feedback loop to the input from an output is adopted.

The symmetrical construction as for which a positive and negative side makes uniform the environments in a chassis and equipment intensities, such as a temperature of each power source and amplification stage and a magnetism, paying attention to the point of having acquired the output signal, by modulating and compounding two power sources, a positive and a negative, with an input signal is adopted.
This is reducing not only distortion generated from a circuitry but the distortion resulting from the problem of the temperature distribution inside a chassis, the influence of magnetic, and the equipment intensity of a chassis.

In addition to the input terminal of an RCA pin jack, the balance type input terminal by a canon type input jack is carried in the input terminal.

The mass toroidal transformer in which low linkage flux and the stable regulation are obtained is adopted as a power-source part. By adopting a very-thick coil, beginning the improvement in a regulation and also suppressing a temperature rise etc. contributes also to the stabilization of a temperature balance.
Moreover, two transformers considered a positive powering and each negative powering as the special purpose, and the reduction of source impedance has also obtained them. Furthermore, adoption and the interval of a double bridge rectification scheme have realized the more exact drive of a speaker.

The protection network which eliminated the relay from the output stage is adopted, the influence on the tone quality by protection network loading is suppressed, and the contact of the signal path is lessened as much as possible.

In order to prevent the oscillation from the outside and deformation of the chassis by internal heat affecting it to a tone quality, the structure where the intensity which cannot deform easily is high is adopted. Moreover, the influence of the magnetism used as strong reservation and a distorted cause is cut by using the aluminum material of a wall thickness sumptuously.
Moreover, in order to suppress an oscillation, vibration proof and the measure against a vibration suppression, such as adopting floating mounting as a power transformer, are put into practice.

In order to realize the design concept of a symmetrical construction certainly, a large-sized heat sink with a high heat-dissipation efficiency ratio is arranged into a suitable position, and equalization of the temperature environment by the side of a positive and a negative is attained.

In order to eliminate the influence on the tone quality by the interference between circuitries, the shielding divided each circuitry section and the cross interferencee is eliminated.

In order to supply the power source stabilized in the exclusive transformer of a positive and each negative, the very-thick code for oxygen-free-high-conductivity-copper audios of six high cores of a conductometric is adopted as a conductor.
It is also insulating doubly and the design which thought the tone quality as important, such as displaying a polarity on adoption of the choice jacket material and a plug, is performed.

The large-sized speaker terminal of the vice sticking-by-pressure type which the speaker cable of a very thick can connect to preparation is adopted as a speaker terminal. Furthermore, it has plated with gold at the terminal area.

It started to parts, such as a transformer, a transistor, IC, and he selected carefully all component partses, such as a material of a chassis, thoroughly, he examined them, and they are adopted.
Moreover, the skilled circuit tester tries listening every set of the product carefully finished by handmade, it checks strictly to the tone quality which does not appear in a measuring instrument meter, and only what was passed on the checking is shipped.

Sticking-by-pressure Chemical

Rating of a mode
Form Class-A monophonic power amplifier
Output power 480W (2ohm)
240W (4ohm)
120W (8ohm)
Input sensitivity/impedance Input1(Coaxial): 1, 0V/10kohm
Input2(Balance): 1.0V / 2.2kohm (3 No. hot)
Output-terminal Speaker: 2ohm - 8ohm
Frequency characteristic 5Hz-100kHz+0 -1 dB
Dumping factor 100 (8ohm)
SN ratio 120dB (A network, a short circuit)
Supply voltage AC100V, 50Hz/60Hz
Power consumption 440W (Electrical Appliance and Material Control Law)
Dimensions Width 460x height 220x depth of 441mm
Weight 47kg