Denon POA S1 Amplifier

According to the philosophy adopted by DENON engineers in their ongoing search for perfection in sound quality, "The ultimate mission of an amp is to impress all lovers of good music." In the past, audio engineers first decided on the type of circuitry to be used and then refined the sound quality around it. This time, however, the circuitry itself became the product of innumerable listening tests, with circuit elements and design being refined according to the sound they produced. These efforts finally gave birth to the UHC Single Push-Pull Circuit and the remarkable POA-S1 Monaural Amp in which it is housed, setting ever-higher standards for power amplifier performance. The challenge facing DENON has been to amplify with dynamic strength and absolute clarity the creative energy transmitted by the artist and to keep apace with the ever-changing musical signal levels. A hefty power supply unit with ample reserves and a power amp, which is capable of supplying pure, dynamic signals to the speakers so that the music is heard with absolute transparency, are the primary requirements. Also required are transient response characteristics that amplify even low-level signals with impeccable precision. No matter how superior the dynamic range or the frequency characteristics may be, these features are meaningless if the amp cannot instantly follow the sudden rises and falls in sound. In the power amplification stage, the POA-S1 incorporates a UHC Single Push-Pull circuit with an ideal UHC-MOS element, the world's first of this type. Thanks to this remarkable circuit, the POA-S1 is able to attain low-impedance drive of 1, 400 watts rated output (at 1 ohm) and superior transient characteristics at low signal levels. The POA-S1 uses a large-current-type MOS-FET that has proven effective at drastically reducing voltage loss. During the conversion of alternating current into direct current, if the transient performance is unsatisfactory when the diode is turned on, the conversion process will be negatively affected and a high-frequency electromagnetic noise known as switching noise will occur, resulting in a serious deterioration of sound quality. The element characteristics of the POA-S1's UHC Power Supply circuit, however, are able to supply power at high speed. This superior ability to respond rapidly to signal level changes has brought about a dramatic improvement in sound purity. The large, high mass toroidal transformers, which normally are a source of vibration, and the large power heat sinks are located above the POA-S1's feet and are attached directly to them in what is called the Direct Mechanical Ground construction. As a virtual mechanical ground for the chassis, this improved design now eliminates any interference caused by vibrations and its adverse affects on the various circuits.