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  • The Absolute Sound (Mar. 2011) - 2011 EDITORS' CHOICE AWARDS
  • Audio Basic(Japan, 2011 WINTER Vol.57)
  • AUDIO REVIEW(Italy, n.316 novemvre 2010)
  • Stereo Sound(Japan, 2011 Winter No.177) 2010 Grand Prix (Integrated Amplifier)
  • Audio Basic(Japan, 2010 AUTUMN vol.56)
  • WHAT HIFI? (Aug. 2010)
  • 6moons.com (Jan. 2010)
  • SoundStage Network (Jan. 2010)
  • Hi-Fi World UK (Nov. 2009)
  • SoundStage Network (RMAF 2009)
  • 6moons.com (July 2009)
  • Preamplifier section

  • The Ai500's solid-state circuitry includes high-speed, low-noise transistors, and direct coupling throughout. Meticulous ground isolation techniques insure superb signal-to-noise ratio. Much care has been taken in the selection of components and the layout of circuitry for low noise, fast response time, and linear frequency response. We are confident that the Ai500 is among the very best preamplifiers on the market, at any price. Small-signal capacitors, where needed, are all 1% tolerance Wima brand resistors.

  • Power amplifier

  • Stello Ai500's output stage employs matched Hitachi MOSFET power transistors in Class AB push-pull configuration. Class AB offers the best trade-off between high performance and high efficiency. Input circuitry, gain stage, drive stage and bias net are April Music's unique proprietary circuitry, with optimum signal transfer and minimum phase shift.

  • D/A Converter

  • Digital signals received via COAX and OPTIC inputs are processed by the digital input receiving circuit. Likewise, the USB signal from a PC enters the USB DAC through the digital input receiving circuit.

  • Power supply

  • Separate power supplies deliver super-stable DC voltages to the preamplifier and DAC circuits. The power amp's supply has tremendous current reserves for lifelike dynamics. With an overlarge 800VA toroidal transformer, fast-recovery rectifiers, and an enormous capacitor bank (90,000uF), the Ai500 will never "run out of breath" even with the most demanding music and the most difficult loudspeaker loads.

  • Connectors

  • Ai500 features Neutrik balanced connectors, gold-plated RCA jacks, and gold-plated speaker terminal binding posts.
    Output Power 150 Watts/CH @ 8 Ohms, 300 Watts/CH @ 4 Ohms
    Output Stage Quad Para Push-Pull Hitachi MOSFET Power Transistors, Class AB
    Power Supply Custom Made 800 VA Toroidal Transformer 90,000 uF Capacitor Bank
    Frequency response 20~45 kHz
    THD + N < 0.05 %
    Volume control Cirrus logic CS3310 digital volume control
    Analog inputs 3 unbalanced analog line inputs
    1 balanced analog line input
    1 BYPASS input
    2 Analog Outputs Pre-out, REC
    4 Digital inputs COAX, OPTIC, PC USB Link, iPod
    Front Panel POWER, BALANCED, CD, TUNER, AUX, DIGITAL, BYPASS, MUTE, Rotary
    Volume Encoder
    Full Function Remote Control
    Dimension 460 (W) X 86 (H) X 400 (D) mm
    Weight 16 Kg (Net.)
      All specifications are subject to change without prior notice.
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