Douk Audio A5 Review: Great Sound, One Omission

TL;DR

The Douk Audio A5 delivers dynamic, full-bodied sound for $99 and offers unusual features, including an adjustable high-pass filter and easily accessible, swappable op-amps. Its biggest weakness is the auxiliary output, which cannot control subwoofer level, so replacing it with a preamp or dedicated subwoofer output would make the amplifier far more practical.

Transcript

in a sea of Class D cheap amplification from China how does one company set themselves apart from the rest of the competition well they do this but I don't want to ruin it this my friends is the Duke audio A5 and it's got a couple of Secrets up its sleeve so sit down grab a cup of coffee and let's talk about the Duke audio A5 it's secrets and why i... Read More

Key Insights

• The Douk Audio A5 is a $99 Class D amplifier using the Texas Instruments 3255 chipset, which the reviewer describes as dynamic, natural, and analog sounding. Its compact, all-metal case also serves as part of the heat-dissipation design when the amplifier is pushed hard.
• The adjustable high-pass filter is the A5's most distinctive functional feature. It can reduce low-frequency content sent to small speakers, which may help prevent excessive bass demands and improve performance when speakers should not reproduce frequencies below roughly 50 Hz.
• The high-pass filter operates through the left front knob and can be switched completely off for full-range playback. Its range extends to 200 Hz, but the control has no detailed frequency markings, so users must adjust it by listening rather than selecting an exact crossover point.
• The auxiliary output is not a proper replacement for a preamp or subwoofer output because its voltage cannot be controlled with the amplifier's volume setting. This omission makes the high-pass filter less useful for integrating a subwoofer directly with the A5.
• The A5 supports power supplies from 24 volts through 48 volts and was supplied to the reviewer with a 32-volt unit. Using a 48-volt supply allowed the amplifier to be pushed harder, although purchasing one separately for about $50 to $70 reduces the overall value proposition.
• The amplifier reached the mid-90 dB range and peaked at 98 dB while driving Q Acoustics 5020 bookshelf speakers from approximately five feet away. The reviewer cautions that listeners seated about 12 feet away in a larger room should not expect the same output level.
• The Douk Audio A5 sounded fuller in the bass and more dynamic than the Fosi Audio V3 in the reviewer's comparison. The V3 placed greater emphasis on the midrange and upper frequencies, while real-time analyzer readings showed smaller bass peaks on material such as the Beastie Boys' “Intergalactic.”
• The removable glass top provides unusually easy access to the amplifier's swappable op-amps and exposes the illuminated internal components. The reviewer considers the transparent design a fun feature, but wishes the LEDs were switchable and the enclosure matched Douk Audio's similarly styled DAC.

Questions & Answers

Q: How does the Douk Audio A5 sound compared with the Fosi Audio V3?

The Douk Audio A5 sounded more dynamic, fuller, and stronger in the bass than the Fosi Audio V3 during the reviewer's comparison. The V3 emphasized the midrange and upper frequencies more strongly and produced less fullness at the bottom. Real-time analyzer readings also showed smaller bass peaks from the V3 while playing bass-heavy material such as the Beastie Boys' “Intergalactic.”

Q: What does the Douk Audio A5 high-pass filter do?

The Douk Audio A5 high-pass filter reduces low-frequency content sent to connected speakers. This can be useful with small or inexpensive speakers that should not be asked to reproduce deep bass, especially models that should not operate below roughly 50 Hz. The filter can therefore reduce excessive demands on those speakers and help users get better performance when pushing them harder.

Q: How do you adjust the high-pass filter on the Douk Audio A5?

The high-pass filter is controlled with the left front knob and extends up to 200 Hz. Because the knob does not provide detailed frequency markings, users must listen to their speakers and turn the control until the balance sounds appropriate. Rotating the control fully left until it clicks switches the filter off and restores full-range output to the speakers.

Q: Why is the Douk Audio A5 auxiliary output a limitation?

The auxiliary output does not provide volume-controlled voltage for a connected subwoofer, so it cannot function like a proper preamp or dedicated subwoofer output. That weakens the usefulness of the built-in high-pass filter because filtering bass from the main speakers normally makes the most sense when a subwoofer reproduces the removed frequencies at a level coordinated with the amplifier's volume.

Q: What power supply can the Douk Audio A5 use?

The Douk Audio A5 accepts power supplies ranging from 24 volts through 48 volts because it uses the Texas Instruments 3255 amplifier chipset. The reviewed unit arrived with a 32-volt supply, which the reviewer considers sufficient for most situations. A 48-volt supply was used to push the amplifier harder, but buying one separately can cost approximately $50 to $70.

Q: How loud can the Douk Audio A5 play?

The Douk Audio A5 reached levels in the mid-90 dB range and peaked at 98 dB while driving Q Acoustics 5020 bookshelf speakers. The measurement was taken in an office with the listening position only about five feet from the speakers. The reviewer notes that a listener approximately 12 feet away in a larger room should not expect the same output level.

Q: Can you replace the op-amps inside the Douk Audio A5?

The Douk Audio A5 allows users to replace its internal op-amps. Its removable glass top lifts away to provide easier internal access than the Fosi Audio V3, which also has swappable op-amps but requires more work to open. The amplifier should be unplugged and allowed to discharge before anyone reaches inside or attempts to change internal components.

Q: Is the Douk Audio A5 worth buying for $99?

The Douk Audio A5 represents good value at $99 for listeners who prioritize dynamic, full-bodied sound, compact construction, an adjustable high-pass filter, and easy access to swappable op-amps. Its principal compromise is the lack of a proper preamp or subwoofer output. The reviewer would also prefer an included 48-volt supply, even if that increased the price to about $130 or $140.

Summary & Key Takeaways

• The Douk Audio A5 is a compact $99 Class D amplifier built around the Texas Instruments 3255 chipset. Its all-metal construction, side ventilation, RCA input, speaker binding posts, auxiliary output, and support for 24-volt through 48-volt power supplies create a simple but flexible package for a small audio system.

• An adjustable high-pass filter distinguishes the A5 from many inexpensive competitors. It can reduce bass sent to small speakers, potentially protecting them and helping them perform more effectively. However, the control lacks frequency markings, and the amplifier has no volume-controlled subwoofer output, limiting how conveniently the filter can support a complete speaker-and-subwoofer system.

• The A5 sounded fuller, more dynamic, and stronger in the bass than the similarly priced Fosi Audio V3 during the review. It also offers a removable glass top, internal lighting, and easy access to swappable op-amps. Despite thoughtful design and good value, a 48-volt supply and proper subwoofer output would improve it substantially.