Topping A50s

Soundnews calls the A50s extremely clean, highly transparent and revealing of small nuances, while DMS hears clinical transparency and surgical precision. Joshua Valour likewise found the balanced output exceptionally clear, neutral and comparable in sound quality to the A90.

The A50s is generally heard as neutral, accurate and uncolored, but not sterile: Soundnews notes a touch of sweetness and warmth through the mids. SoundStage Solo found it natural and slightly mellow, with subtly softer treble and fuller bass than the compared Magnius; DMS noted a small lift in the extreme treble.

Reviewers repeatedly praise the amplifier's speed, punch and authority, especially from its 4.4mm output. It drove LCD-X headphones without audible distortion and took HE6se headphones to satisfying loud levels without strain, although SoundStage Solo found its thermal protection could shut the amplifier down when pushed close to its limit for extended periods.

DMS reports an extremely low noise floor, and SoundStage Solo heard no noise at all with Campfire Audio Rai Penta IEMs. Joshua Valour also describes very clean performance with highly efficient IEMs, supporting its suitability for sensitive headphones as well as larger designs.

The A50s has earned strong reports with sensitive Rai Penta IEMs, LCD-X planars and difficult HE6se headphones, with reviewers particularly favoring the balanced output for its added ease and control. Its two gain settings and 4.4mm balanced output broaden its usefulness, but the aggressive thermal protection circuit makes prolonged near-maximum use with exceptionally demanding headphones less reassuring.

Reviewers describe the compact chassis as dense, very well made and carved from a single aluminum block. SoundStage Solo's measurements and listening also suggest careful engineering, though the external wall-wart and thermal protection behavior are less luxurious aspects of the execution.

The compact desktop layout includes RCA inputs and pre-outs, a 6.3mm single-ended output, a 4.4mm balanced output, and selectable 0dB or +6dB gain. It is straightforward and space-efficient, but it is purposefully a pure analog amplifier without onboard DAC functions, digital inputs, remote control or balanced line inputs.

At roughly $200, several reviewers consider the A50s an exceptional buy: Z Reviews questions how it can offer this combination of power and cleanliness at the price, while Joshua Valour calls it an absolute bargain for its feature set. Soundnews goes further, finding its high-end sonic performance competitive with far more expensive amplifiers.