A-S2000

The A-S2000 achieves fully balanced signal transmission from input to output (balanced design refers to the use of two signal conductors that have equal impedances to ground). Balanced transmission is capable of cancelling noise produced internally and externally, and so is considered to be an ideal amplification method, eliminating the sound quality degradation caused by noise. If it is only partially adopted, however, it will be largely ineffective and may even have negative effects. The A-S2000 is the world’s first integrated amp to offer full-stage balanced transmission, combining high power output with good sound texture and outstanding S/N performance. Its capabilities will be heard to best effect when paired with the CD-S2000 CD player, which employs the same principle.

The Floating Balanced Power Amp configuration is completely different from the pure complementary circuit design that has been the mainstream of HiFi amps for nearly forty years. It adopts an output element having identical polarity on the plus and minus sides of the output stage, with both sides having their own power supply and feedback, thereby achieving total symmetry of pullable operation at the output stage. The power supply unit has four floating elements (no restrictive grounding connections), two for each channel, so plus and minus and completely symmetrical.

To ensure ideal fully balanced operation, the volume and tone control systems must be extremely precise. Conventional analogue volume systems suffer from gang error, and cannot achieve sufficient accuracy, even when using high precision parts. Therefore, for the A-S2000 we developed a unique method: cancelling out slight precision differences by the parallel operation of three high sound quality digital volume ICs for each channel and operating the system with an analogue encoder. When using the bass and treble tone controls, each of the three volume elements is applied in succession, and during tone default, three equivalent volume elements for each channel are used for volume adjustment. This ensures the best sound quality during both tone control and default operation.

The A-S2000 has four large capacity power supplies for the power amp that are completely isolated from ground. Shunt type local regulators that prevent degradation of sound quality by amperage fluctuation ensure a clean and stable power supply for the preamp. Naturally, parts that directly affect sound quality such as the large power supply transformer and carbon sheath block capacitors were chosen only after careful evaluation.

The A-S2000 has a completely symmetrical construction intended to achieve the ultimate in integrated amp left-right separation, equal to that of separate amps. A central reinforcing bar ensures that the chassis is rigid and stable.