Yamaha A-S1100 Integrated Amplifier
Fully Balanced Floating Power Amplifier With MOSFETs and All-Stage Full-Discrete Configuration Provide Illustrious Sound: Yamaha A-S1100 Integrated Amp Also Has Discrete Phono Preamp
While the alluring wood side panels, retro VU meters, and under-the-hood architecture draw your eyes, the illustrious transparency of the Yamaha A-S1100 integrated amplifier lures your ears. Providing both dedicated single-ended and high-grade integrated amplification, the symmetrically designed A-S1100 is all about emotional involvement and pure, meticulously defined sound. A floating and balanced power amp with MOSFETs, all-stage full-discrete configuration, reference-grade volume control, and massive power supply ensure edge-of-your-seat dynamics while a discrete MM/MC phono preamplifier invites you to enjoy analog warmth well into the early-morning hours. 100% Music Direct Guaranteed.
Balanced Power Amplifier with MOSFETs for Warm, Involving Playback
The basic design of the A-S1100 power amplifier circuit features Yamaha's unique floating and balanced power amplifier technology. Adopting output elements with the same polarity on the plus and minus sides of the output stage – along with completely separating the NFB (negative feedback) circuit and power supply into a total of four plus and minus sides of the left and right channels – results in a thoroughly symmetric push-pull operation of the output stage. Completely floating the entire power amplifier circuit from the ground removes any negative impact of minute voltage fluctuations or ground noise. Moreover, the output elements are comprised of MOSFETs, which provide a warm and natural sonic characteristic in the audible playback. The use of MOSFETs, which have the same polarity on the plus and minus sides, further evolves the ideal symmetrical design to eliminate sound quality variations due to difference in polarity. This results in sound with a superior signal-to-noise ratio and superbly well-defined sound fields. And since A-S1100 employs a dedicated single-ended amplifier, it provides excellent response in the amplification of single-ended analog sound from all kinds of audio sources such as CD players and D/A converters.
All-Stage Full-Discrete Configuration and Discretely Configured Phono Preamp
A-S1100 adopts an all-stage, fully-discrete configuration through all sound circuit stages using only the most meticulously selected, high-precision parts from input to output (applicable during tone control circuit defeat). The slew-rate of the audio signal has been improved to bring lively and strong response to high musical notes. Moreover, the tone control circuit lets you switch to the defeat-state and enable a full discrete configuration that bypasses the op-amp IC of the internal circuit. A-S1100's phono preamp is comprised of a MC head amp and an equalizer amp, each discretely configured, resulting in a rich sound with pronounced musicality when playing vinyl records with both MC and MM phono cartridges.
Low-Impedance Design Ensures Powerful, Taut Low-End
By strengthening the capacity of the high-current route (raising the section area of the cable core wire to about 60% of that of the A-S1000), and by pursuing thorough low-impedance design and forming screw-clamped wire connections of major ground points, A-S1100 boasts excellent speaker drive power with a damping factor of more than 250 (8Ω, 1 kHz). Along with the large capacity power source transformer equipped with an EI core, this design delivers strong and uplifting bass reproduction.
High-Grade Electronic Volume Control for Excellent Purity and Transient Response
Yamaha utilizes a high-quality digital volume control designed by New Japan Radio Co., Ltd. It consists only of ladder-type resistance, removing the impact of slew-rate decline or coloring of the sound. This delivers higher purity in the sound and excellent, fast response to large volume changes and steep transients. Moreover, the tone controls employ a triple-parallel method, minimizing the detrimental impact on sound quality seen with straight-line tone controls. In addition, the bass, treble, and common circuits each utilize simple construction in which the NFB of the amp is not used and the CR elements are simply fixed in a straight line. This ensures exceptional sound reproduction even when tone control is applied.
Massive Power Supply Unit and Symmetrical Design
A-S1100 employs an original EI transformer, carefully customized for optimum compatibility with the chassis. Combining four large-capacity carbon sheath block capacitors delivers an energetic sound. Moreover, since the control amp and control system is equipped with twelve shunt type local regulators that prevent deterioration caused by current fluctuation, a clean and stable power supply is achieved. The EI transformer is mounted on the chassis using a brass washer, restricting internal vibration that would result in noise. In addition, the left-right symmetrical construction with the power supply in the center and the ends of the power amp blocks achieves greater separation of the left and right channels. This is necessary for proper two-channel stereo reproduction and ideal weight balance. Featuring a fine-tuned center frame that extends from the front to the back of the casing, A-S1100 has superb mechanical rigidity and installation stability that dramatically lessens the impact of external vibrations on sound quality.
Obsession With Quality Stems to Speaker Terminals
Meticulous obsession with quality continues through to the speaker terminals, the last and crucial link in the audio chain. The screw-type terminals with originally-designed handles are created by cutting pure brass. This enables a secure connection with no reduction in sound quality. Contoured to the shape of human fingers, they not only look beautiful, they can be turned easily and fastened tightly with minimal effort. They are also compatible with connections that use banana plugs.