Product Description

Faced with exactly the same challenges as the M1.1, the A1.5 embodies the same sophisticated, modular and scalable approach. It might be (slightly) smaller than the M1.1 and around two-thirds of its weight, but it’s still four amplifiers in one. It still offers the same adaptable, software controlled topology, adjustable input configuration and gain, user selectable global feedback ratio and cost-effective upgrade path. It offers exactly the same, incredibly short signal path, fully discrete, fully balanced and fully complementary circuit, built with the same carefully selected components to the same exacting standards. Even the casework, although shorter, has the same footprint, uses the same construction and includes the same mechanical grounding/stacking system. In fact, in every important way, the A1.5 is, quite literally, an M1.1 writ small – or, in Hollywood terms, “Honey, I shrank the amp…”.

Physical And Conceptual Modularity

  • Modular input boards to match system topology (one or two inputs as required)
  • Output stage can deliver 2x 150W RMS into 8 Ohms stereo, 150W into 8 Ohms mono (high-current), 550W mono (bridged) or 2x 150W bi-amped (single input, differential channel gain and global feedback settings)

Analog Input Stage

  • Pure class A, fully symmetrical circuit topology
  • Fully discrete, ultra low noise, high slew rate design
  • DC coupled with no series capacitors in the audio signal path
  • Gain adjustable through 24dB in 0.5dB steps

Analog Output Stage

  • Pure class A ultra low noise driver and class AB pure follower power stage
  • ExactBias circuitry ensures constant bias, independent of room temperature and amplifier loading
  • Constant monitoring of output power and temperature
  • User configurable display will show amplifier status, power output etc
  • Customized Argento loudspeaker binding posts, accept spades and banana connectors

Power Supply

  • 1700VA power transformer mounted on separate, mechanically isolated chassis bed to eliminate mechanical vibration
  • Magnetically and electrostatically shielded transformers to reduce noise and EM interference
  • Hyper fast, soft recovery diode bridge rectifiers meet dynamic demands without strain
  • Twin 82,000uF custom-built, ultra low ESR reservoir and filtering capacitors

User Adjustable Global Feedback

  • Ratio of Global to Local Feedback can be adjusted from 0% to 100%, in six steps (0, 10, 20, 40, 70, 100%) via the user interface or control app
  • Allows user optimization of amplifier/speaker interface, especially lowfrequency damping relative to speaker/room interaction
  • Each channel can be adjusted individually to control specific drivers/ranges in bi-amplification modes

Light Touch Protection

  • No output relay in signal path; full short circuit protection
  • Non-invasive output stage voltage, current and temperature monitoring protects your amplifier – and your speakers