Douk Audio G4 100W Mono Digital Amplifier Review

The Douk Audio G4 is a mono digital amplifier priced at $44.99, built for two jobs: driving a subwoofer, or acting as a full-frequency channel amplifier for a single speaker. It is a class-D design in a small aluminium chassis, and the listing is upfront that it is a mono amplifier, so stereo output requires two (or three) units.

A B/M switch selects the operating mode, moving between full-frequency use (20Hz-20kHz) and subwoofer use (20-200Hz), and the speaker matching follows suit: 3-10 inch full-range or crossover speakers rated 10-200W, or 4-12 inch subwoofers rated 40-200W, all at 4-8Ω impedance. Rated power is 100W with a peak of 300W, and THD is quoted at 0.001% with SNR at 103dB. Two NE5532 op amps and a Texas Instruments TPA3116 chip handle the signal, and the maker says there is no audible noise even at high output.

The inputs are a 3.5mm AUX socket and an RCA connection, covering devices with different output types. When fed a stereo signal, the G4 combines the left and right channels, analyses and processes the signal and frequency response, and then amplifies it, which the listing says results in purer low-frequency filtering and more efficient power consumption. Two units can drive left and right channels separately to keep them isolated from each other, making the G4 equally useful as a stereo pair or as a bass amp added to an existing 2.0 system. It runs on DC 12-24V through a 5.5/2.5mm jack, measures 105 x 85 x 30mm, weighs 240g, and the 19V power supply is an option at checkout.

Douk Audio ships worldwide with free and expedited options and country-based pricing. Orders under 2kg travel by airmail (10-25 days) and anything over 2kg by DHL, UPS or FedEx (5-8 days); at 240g the G4 ships by airmail. Import duties and customs charges are the buyer's responsibility. All items come with a 30-day free return or full refund and a 1-year warranty, excluding orders placed by mistake, man-made damage or misuse, a subjective change of mind, and anything else outside the warranty terms.