I was fortunate to stumble upon a batch of brand-new power amplifier modules, all of which are classic mass-produced models from different periods, crafted with mature thick-film technology. After professional tuning, their sound quality performance, relying on the rigorous quality control of high-precision semiconductor manufacturing processes, has reached a level that is difficult for amateur DIY to match. I have made a simple comparison between this thick-film module and a classic power amplifier chip of the same power level, even though the latter is a highly respected version among players. This thick-film module still has significant advantages in all aspects - not only does it have a broader soundstage and finer resolution, but its low-frequency power is also significantly different, like the gap between professional players and amateurs.
These thick-film circuits were mostly customized products for professional audio brands back in the day. In the early days, many well-known manufacturers used them to build power amplifiers. Their unique sound quality not only influenced an era but also became a highly recognizable sound imprint in the youthful memories of our generation, leaving a lingering aftertaste every time we listen to them. The original manufacturer producing these modules was later acquired by an international semiconductor giant. The new manufacturer, while continuing the original mature technology, incorporated its own unique design philosophy, resulting in increasingly superior performance of subsequent products. These products are still adopted by many well-known audio companies worldwide, covering various fields such as professional and civilian use.
Product Specifications
This device is developed and produced according to standard products, with all components being original and genuine. It is equipped with the Bluetooth 5.0 chip paired with AC6905 to enable wireless music playback with various portable products. This device is powered directly by a 220V power supply, making it convenient to use. The all-aluminum chassis is crafted with precision and ensures good heat dissipation
(1) Adopting the brand-new original authentic STK4140MK2 chip.
(2) Equipped with a built-in custom pure copper power transformer for power supply, it can be directly plugged into a 220V outlet.
(3) The radiator is directly connected to the upper and lower cover plates of the chassis, increasing the heat transfer area and improving the cooling effect.
(4) It adopts high-brand filter capacitors and ALPS16 type volume potentiometers.
Basic performance parameters:
Operating mode: Class A/B
Static current: 60mA
Output power: 25W/8Ω, distortion 0.1%. Currently using STK4140MK2. Frequency response: 20Hz to 50KHz
Dynamic range: >100 dB
Dimensions: 130*55*228MM (excluding protruding parts)
weight: 2.3KG (including packaging, 3KG)
