Questyle M15 USB DAC Review

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Questyle M15 USB DAC Review

The new Questyle M15 is the second dongle DAC from the company after the M12 which was launched about a year ago. Doubled the DAC chips (ES9281AC PRO) inside, doubled the audio outputs by adding the balanced 4.4mm port, doubled the power output (M15’s balanced compared to M12’s unbalanced), and almost doubled the price (from $139 to $249). What about the sound performance, is it doubled too? Let’s find out.

The M15 contains two of Questyle’s patented CMA (Current Mode Amplification) SiP modules, for a total of four CMA amp engines. This quadruple drive amplification circuitry gives an outstandingly strong output that can drive almost any headphone. Questyle’s Current Mode Amplifiers are characterized by their small footprint, low voltage operation, and minimal power consumption. Current amplification has a naturally low impedance, affording the M15 a bandwidth up to1MHz, and distortion as low as 0.0003%.

Questyle M15 DAC Review

The CMA SiP modules inside M15 are a miniaturized application of their desktop engineering principles which made Questyle win over 20 international awards since 2015, such as the CES Innovation Award, iF Industrial Design Award, VGP Lifestyle Award, etc.

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2x Current Mode Amplification (CMA) SiPs

The Questyle M15 supports for 32-Bit/384kHz PCM and native DSD256 decoding. It also supports MQA decoding.

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Questyle M15 has got two headphone output ports, one single-ended 3.5mm and another fully balanced 4.4mm port. It has two level gain modes, low and high gain. High gain modes will enable the users to use high-impedance headphones with the M15.

Questyle has designed the M15 with a CNC-machined aluminum chassis and a transparent front window. Through the transparent window, we can see the entire circuitry inside the M15 and two LED indicators. One light tells us about the active file bitrate while the other indicates the active gain level.


  • Questyle’s patented CMA modules.
  • Four total amplification engines.
  • Dual ES9281AC PRO Sabre DAC chips.
  • Dual Headphone Output Ports (3.5mm Single-Ended+4.4mm balanced).
  • High-res PCM, DSD, and MQA signal support.
  • Clean output performance with ultra-low noise floor.
  • Class-leading ultra-low Distortion.
  • Two-level gain switch.
  • LED indicators for gain and active bitrate.
  • Low power consumption TOREX power chip.
  • Minimalistic design with metal housing and transparent cover.
  • Supports multiple devices including Smartphones, Tablets, Windows, and Mac systems.
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  • Decoding Parameters: PCM 32-Bit/384kHz, DSD256.
  • Output Interface: 3.5mm single-ended, 4.4mm balanced.
  • Output Power (3.5mm): 11.97mW @ 300Ω, Vout (max): 1.895Vrms. THD+N=0.00045%
  • Output Power (4.4mm): 22.60mW @ 300Ω, Vout (Max): 2.624Vrms. THD+N=0.00057%
  • Frequency Response: 20Hz-20kHz±0.1dB.
  • Dimensions: 61.8×27.2x12mm.

What’s In The Box

I would like to thank Questyle for providing me with the review sample of the M15 DAC


Before I begin I want to say that the M15 is a perfect example that we can’t evaluate the sound of a DAC by looking at its DAC chips and making a general statement. There are many variables when it comes to real-world performance. The implementation, combining good hardware with well-done firmware, proper amplification, filtering, etc. differentiates the final sound. 

My first observation was actually not in tonality but in the staging which seems to open up considerably compared to other dongles. Placement is excellent and there is lots of depth along with width and height but most of all a very good micro staging ability.

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Natural, realistic, organic signature with plenty of details. That is how I describe the M15. It is not only organic but also technically advanced as well. It is one of the best DACs I have ever heard, to be honest.

First of all, it sounds quite coherent. There are no dips, no humps. It is flat and it is accurate. Technically, the separation and the imaging feel absolutely marvelous. The bite, the attack & decay is not fierce, it’s rather fast and agile but more effortlessly. There is plenty of air between the instruments and combining that with a precise, holographic staging results in very accurate imaging.  With the M15, every instrument on the stage has a dedicated, clear position. The M15’s resolution is quite impressive as well. The clarity is top-notch. 

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Thanks to low power consumption TOREX power chips Questyle M15 never gets hot during use, even a little bit


Punchy, authoritative, defined. Sub-bass presence is ample. Overall bass response is very good, just like the rest of the range. The note weight is the key here. It does not feel tinny or dry at all. Necessary harmonics are presented effortlessly by the M15. The bass is quick, agile, and snappy as well. This makes transients a joy to follow. The dynamics are excellent, as well as the control. The bass never bleeds into mids and never lags behind. Well done.

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Articulate and coherent. The midrange is just right. Stringed instruments sound breathy and organic to my ears. The effortless presentation of M15 does not surprise me here, as well. Mids are thick when they need to be so there are no problems with the tonality here. Vocals do not feel saturated, artificial, or thin, in fact, they feel life-like. Questyle tuned this range delightfully. Macro-detail retrieval is especially impressive here. Female vocals are delicate, detailed, and transparent. You get to hear and follow every breath, every nuance with ease. The upper midrange has ample energy and it is vivid. Don’t get me wrong here, it is not overly bright or sharp. Just the contrary, in my opinion, it offers a perfectly balanced upper midrange. If you are in this market for a long time, you know it is a crucial area, and tuning it, is hard.

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Very detailed, precise, and clear. Highs offer excellent clarity and detail while being articulate and coherent. You keep hearing the word coherent from me, and yes it is true, every frequency range is in complete sync with each other. The M15 has brilliant tonal balance. No overlapping, no bleeding. You will never hear the treble overpowering the midrange with this DAC. Furthermore, the treble extension is impressive and blends in perfectly with the rest of the spectrum.

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I love red on black, perfect combo right?


The Questyle M15 is an excellent DAC. It looks gorgeous. It sounds organic, detailed, and effortless. It has a great tonal balance and it offers precise imaging. Not many USB DACs can do that. Getting the dynamics, tonality, and technicalities right is hard. Questyle surely did a lot of R&D for this device to maximize the performance of dual ES9281AC PRO DAC chips. It is one of the best DACs I have ever heard, to be honest.