Yamaha A-S1000
Natural Sound Stereo Amplifier
Yamaha's All-New Approach to Achieving Superior Performance
The development of the modern audio amplifier began in the 1960s with the introduction of full-transistor amplifiers. In the 1970s, pure complementary configured power amps appeared, made possible by high output PNP/NPN transistors, and became the dominant type of analogue amplifier. Now digital amps have become popular for their high conversion efficiency and superior operating precision, as well as for their lower weight, size and heat production as compared to analogue amps. Some manufacturers of audiophile-quality amps are working to improve the traditional pure complementary analogue amplifier, while others are seeking to achieve higher sound quality from digital amplifiers.
Yamaha has developed a third approach that we believe is superior to the other two. The Floating Balanced Power Amplifier uses patented technologies featuring power transistors with the same polarity at the output stage to achieve completely symmetrical operation. First introduced in the A-S2000, this method is also used to good effect in the A-S1000, which combines a floating balanced power amp section with a high quality pre-amp section. Simpler in configuration yet with many of the same sound quality features as the ultra high-end A-S2000, it will deliver excellent performance with the CD-S1000 Super Audio CD Player and other high quality components.
High Performance Amplifier that Brings Out the Best of Other Components
The power amp, power supply, and phono EQ circuits that contribute to the A-S1000's high sound quality are identical to those of the A-S2000, while the line amp section and volume and tone circuits are nearly the same. Designed to take full advantage of the excellent sonic qualities of the matching CD-S1000, the A-S1000 will also bring out the best of other high performance components.
Floating Balanced Power Amplifier
With the A-S2000 and now the A-S1000, Yamaha has taken the bold step of using a floating balanced configuration to update the power amplifier for serious music fans. This method, which is completely different from the pure complementary circuit that has been the main type used for the past four decades, features identical polarity on the plus and minus side of the output stage. By completely isolating the plus and minus sides of the left and right channels of both the NFB and power supplies, it achieves perfectly symmetrical operation in the output stage. The use of four sets of floating power supply units (not connected to earth), provides further operating precision. The result is very low levels of noise and distortion for exceptionally pure and transparent sound quality.
Triple Parallel Electronic Volume and Tone Controls
Conventional audio amps have the volume and tone control circuits arranged in series (in line); when the tone controls are used, the signal route becomes more complicated, which can lower sound quality. Many high quality amps therefore have a default circuit that can be selected to bypass the tone controls, but this forces you to choose between tone control and optimum quality. The A-S2000 and A-S1000 are the first amplifiers to avoid this problem by employing triple parallel electronic volume and tone controls, providing maximum sound quality even when the tone controls are used (signal goes through fewer ICs, so there is less noise). When the tone controls are set to the centre position, the passive element used for tone control is bypassed, so the three volume elements connected in parallel operate solely to drive and control the volume, for more efficient use of the power output. Each volume element is an ultra-high quality device and an analogue potentiometer is used to provide a very smooth operating feel.
Fully Discrete Phono Equaliser and MC Head Amp
The A-S1000 uses a fully discrete phono equaliser circuit, making it's quality comparable to those in high-end control amps. With its high priority on maximising musical response, it is also equipped with a discrete head amp for MC cartridges. If you enjoy listening to records via high performance cartridges, the A-S1000 is an ideal choice.
Power Supply
Power is provided by four large capacity power supplies that are completely isolated from earth. In the pre-amp stage, the combination of a low-current circuit that prevents the occurrence of noise due to current fluctuation and 12 shunt regulators supply all stages with clean and stable power. The extra-large power transformer, the carbon sheath block capacitors and other parts that directly affect sound quality were chosen only after extensive testing.
Symmetrical Construction
Although it is an integrated amplifier, the A-S1000 has a completely left-right symmetrical construction that makes it virtually the equal of separate amps. A central reinforcing bar ensures that the chassis is totally rigid.
Specially Designed Feet
The base is equipped with height adjustable, solid steel feet that maximise stability and thoroughly dampen any external vibration.
RRP: $2,499
