The AK-280 audio amplifier is often advertised on Aliexpress and Temu. I received one as a gift due to my frequent purchases on Temu, though I had to buy other items too. Due to limited information about its performance, I’ve decided to review it myself, ideally in English.
AK-280 audio amplifier
I chose not to conduct tests on YouTube for the AK-280 amplifier, as its low cost doesn’t warrant extensive testing; you get what you pay for. The unit from Temu lacks a PSU and isn’t close to 600W. The YD7377 power output IC is rated at 20W per channel into a 4 Ohm load in a bridge-tied configuration. Simple maths: Vcc^2/8RL or 144/32 equals 4.5W, multiplied by 4 gives 20W, but likely less due to output transistor saturation. When running from a car’s cigarette lighter or aux, the battery under charge is about 14V, yielding around 25W in BTL config.
Despite the 600W claim by manufacturers, this marketing strategy seriously remains questionable.
AK-280 audio amplifier pre and tone 4558 chips
AK-280 audio amplifier pre and tone 4558 chips
Considering the price of R280.00 or $19.00, the performance of this amplifier is reasonable. Testing it with a sound card as the source and a 3A 12V power supply, the output is approximately 15W. Using a computer ATX supply notably reduced distortion at 75% volume, though not verified with a signal generator and scope.
The YD7377 audio chip, equivalent to the TDA7377, claims to deliver 40W per channel into a 2 Ohm load, but adequate heatsinking is required for reliability. The chassis of the AK-280 acts as the heatsink, and its contact with the chip is uncertain.
The lighting around the volume control is somewhat distracting, a common feature in budget amplifiers, though some high-end models also have it. Personally, I prefer less flashy designs. The manufacturer should consider putting in BT.
Bottom line: The main advantage of this product is its price and the ability to operate directly from a 12V battery, making it portable when using Lithium Ion or LIFEPO4 batteries. It can be easily housed in a box with speakers to create a portable audio system for children or a barbecue area. Amazon users give the little amplifier quite good reviews except the false 200W per channel claimed peak output.
The main con here is the ludicrous focus on an impossible power-to-price ratio which may present challenges 🙂 , and the uncertain quality of contact between the heatsink and output chip. Additionally, distortion was audible at a 75% setting with a 3A 12V power supply. The supplier should recommend an appropriate power supply. An ATX supply improved performance, as would a car battery. Note that Amazon does sell this product with a 12V 5A supply.
Nowadays, a lot of even entry level units come with Bluetooth, something to consider.
For the price, something the home tinkerer may want to experiment with, without breaking the bank.