Margules U-280 SC 30th Anniversary – Celebrating the Anniversary

Mexican company Margules has released a special edition of its U-280 SC tube power amplifier to celebrate the model’s 30th anniversary. The amplifier retains the key technical solutions of the original design, which the manufacturer has continued to refine over the past three decades, including pure Class A operation, selectable output-stage modes, and a proprietary automatic tube bias adjustment system.

The Margules U-280 SC 30th Anniversary is equipped with the Active Servo Bias system, which monitors the operating parameters of the output stage in real time and automatically adjusts tube bias. As a result, owners do not need to perform manual bias adjustment, while the amplifier can accommodate several different types of output tubes. It comes standard with four KT88 tubes but also supports 6550, KT90, KT120, and KT150 tubes. The input stage uses four 12AU7 tubes.

The amplifier can operate in either triode or ultralinear mode. In stereo configuration, it delivers 25 watts per channel in triode mode and 50 watts per channel in ultralinear mode. When configured as a monoblock, output power increases to 55 and 100 watts respectively. Other design features include the absence of global negative feedback, an independent regulated power supply, and the proprietary BEFS system, designed to manage the amplifier’s interaction with the loudspeakers’ back electromotive force. Input attenuators also make it possible to connect a source directly to the power amplifier when required.

The Margules U-280 SC has a specified frequency response of 20 Hz to 40 kHz at –3 dB, while total harmonic distortion does not exceed 0.08%. According to the manufacturer, these circuit solutions represent the company’s ANA, or Aligned Neuro-Acoustics, concept, which focuses not only on measurable performance but also on the spatial and harmonic perception of musical material.

The Margules U-280 SC 30th Anniversary tube power amplifier is handcrafted in Mexico and is already available for purchase. The recommended retail price of the anniversary edition is $12,000.