Disclaimer: I would like to formally thank Jack from Apos Audio for providing us with two units in exchange for an impartial and honest review, despite the lengthy delay. On behalf of the team at the Headphone List, we thank Campfire Audio for their generosity and trust in THL.
Summary:
The Apos Audio Gremlin and Merlin thrive on the fundamentals — 1.25 W of clean power into a 32 ohm transducer load and a reputation-preceding AKM DAC. Don’t let their modest price tags fool you: this combo delivers a gentle, neutral signature with subtle colourations on uncomfortable peaks.
Pros:
+ Gremlin delivers exceptional ‘tube’ power with a touch of warmth
+ Merlin provides clean modulation of sound
+ Affordability and customisability.
Cons:
+ Lack of input/output versatility on the Gremlin
+ DIY aesthetic and exposed circuitboard
Introduction
The Apos Audio X, like the now-defunct Massdrop, is a community-driven hub run by Apos Audio, testing ‘ideas’ and ‘projects’ with their audience to ascertain their level of desire. By assessing user interest on a per-concept basis, Apos Audio can accurately assess what users are truly looking for.
Projects attracting enough excitement then migrate from the drawing board to the manufacturer’s warehouse. Historically, Apos Audio has collaborated (Audio -Technica), audio personalities (Z-Reviews) to release co-branded products specifically for their customer base. However, all of their previous releases share two common denominators: affordability and performance.
Today, we’re paying closer attention to the Gremlin and Merlin, the former being a full Class A balanced tube amplifier and the latter being a fully balanced AKM DAC co-designed by Geshilli Labs. A throwback to widely-lauded technologies of yesteryear, what was once seen as wallet-exhaustive acquisitions now only costs $120 and $160, respectively. The Apos Audio Gremlin and Druid can be purchased via the links below:
Apos Audio’s official website:
Apos Audio Gremlin headphone amplifier
Amazon:
APOS X Geshilli Merlin DAC (Amazon)
Unboxing

The Gremlin and Druid each come shipped in a cube-shaped box, replete with mystical theming and rustic serif fonts (reminiscent of the now-defunct Metal Magic Research or MMR).
Inside the box, you’ll find that its innards are tucked away securely in layers of laser-cut styrofoam and padded inserts. You’ll be happy to note that there were no visible scuffs on the Gremlin or Druid’s acrylic panels.
Apart from that, you’ll find the following in their respective boxes:
- The Gremlin/Merlin
- Apos Audio-branded vinyl stickers
- Instructions
- Powerbricks per unit
- USB-C to USB-C cable (for Merlin only).
My only main grievance here is the lack of XLR-balanced interconnects for both units. Given that both units were designed with stacking and synergy in mind, the provision of these necessities in either of their packages would’ve been welcomed.
Design and durability

Notes: Given that both the Gremlin and Merlin share a near-identical design, we’ll review both units concurrently in this section. Also note that the stacker can be purchased as an add-on for $15.
Both the Gremlin and Merlin, being the products born out of community interest, celebrate their birth with a ‘DIY aesthetic’, their assembly comprising a series of acrylic panels held together by a series of metal poles and screws. A clear visual point of interest is the hollowed-out, exposed innards of circuitry and op-amps.
For the audio nerds out there, being able to visibly see the op-amps and DAC chips unperturbed could be a plus point. Minus the potential build-up of surface dust, this is a matter of personal preference.
Overall, given their individual price points, the Gremlin and Merlin feel substantial, with an even plinth/base with no rattle on my computer desk.
Turn to the next page for ‘Features’