Questyle M18i – A Perfect Design Still Casts A Shadow.

Disclaimer

• The review item is a personal unit. All opinions remain original ideas of my own, there was zero influence from any 3rd party or external opinions throughout the review.
• No EQ or filter presets were used during the entire sound evaluation.
• Sound evaluation are kept neutral and does not include 3rd party accessories (ie; filters, eartips, cable, irreversible/reversible mods)

Overall Rating: 3 out of 5

Introduction

Shenzhen Questyle Audio Co., Ltd or better known as Questyle is one of the biggest names in high-performance audio when it comes to high-end DACs (Digital Audio Converter) and amplifiers within the audiophile community. Some of their best masterpiece such as the CMA Fifteen and CMA Eighteen Master are considered as one of the best desktop solutions money can buy. In the portable audio segment, Questyle is highly-regarded for the release of the M15i which quickly gained a legendary status among end-users and reviewers alike for its price to performance. In recent weeks, Questyle has announced the release of their latest addition into their portable audio catalogue.

With me here is the brand new Questyle M18i which retails for $349 on Questyle’s official website. Apparently, the M18i has loads of features that are carried over from the CMA18 except for the obvious compact design and smaller battery capacity. But apart from that, the M18i is redesigned with a dedicated button to access the available modes and a high-low gain button. Now, with all of those details said, let us dive into the review for the Questyle M18i.

Packaging and Accessories

Continuing the minimalist design philosophy, the presentation and unboxing experience for Questyle M18i is no different with the rest of their products. We’ll just briefly go over what’s on the outer box first before dwelling in much deeper. On the front, there’s a technical drawing of the M18i followed by some Questyle branding and the name of the model. On each side of the box, there’s a Snapdragon Sound logo which devices that support this feature will definitely benefit from it and also a tag that reads the M18i is made compatible for iOS devices such as your iPhones, Macs, etc. Meanwhile, at the back users will find the basic specifications about the M18i, details about Questyle and including other miscellaneous details such as the LDAC logo, etc.

The packaging features a slide mechanism which you can pull via the ribbon, which then unveils the content of the box. Straight out of the box, you’ll be greeted with a manual card which reads out the instructions on how to use the dongle, alongside its features and a warranty card. Next, you’ll find the M18i itself resting snug in-between a foam cutout. At the bottom of the box, you’ll find a USB-C to USB-C cable with a Questyle branding and a USB-C to USB-A adapter. Unfortunately, one downside particularly for those with iPhones that still use Lightning cable will require an adapter or a 3rd party cable if you plan to connect it wired to the dongle.

Design and Ergonomics

In terms of design, Questyle has kept the similar design and styling for the M18i with the rest of the dongles inside their catalogue. Such as the M15 series and M12 series, which came in this solid rectangular metal enclosure with an anodized black finish to further highlight the soft and hard edges of the design. There is no flashy, gimmicky design on this dongle as users will only find this dongle has a large glass panel on the front, with all control buttons are on the left and a Questyle branding, model name laser engraved at the back similarly to what you’ll find on their other dongles. Measured at 75mm x 35mm x 14.5mm (L×W×H). The M18i is slightly larger than the M15 series, in fact it’s almost the same size as the iBasso Nunchaku or DC Elite.

Typically with Questyle dongles we’ll be able to see all of the components inside of the dongle via the glass panel in the front but this is not the case with the M18i. Instead, what you’ll be getting is a large glass panel which as you all well know, you’ll constantly have to clean it from dust and fingerprints. There’s also a tiny OLED screen with non-adjustable brightness that shows all of the details you need to know such as the modes you are in, high and low gain notification, bit-rate display and much more. Moving to the control buttons on the left, you have your operational switch that slides solidly with a satisfying click. This switch allows you to change to Bluetooth, PC, and Smartphone which we’ll discuss more in the features. There’s also an MFB (Multi-Function Button) which works as your gain switch as well as a play/pause button and skip/rewind during Bluetooth mode. Last but not least, a plus and minus button for your volume control which can be adjusted from 0 to 60 and finally an On/Off button which turns the device within a single click and when the power button is pressed again it will dim the display. Pressing the power button for 3-4 seconds will turn off the device and apparently users could factory reset it by pressing the power button for 10 seconds.

All of the buttons feel solid with a deep tacky sound when pressed, it reminds me of those metal buttons usually on high-end AV receivers. For the outputs, Questyle included a 3.5mm single-ended jack and a 4.4mm balanced jack at the bottom of the dongle. Additionally, there are two USB-C ports on the chassis of the M18i, one on the top is for the main connection from the dongle to a host device on Mobile Mode. Meanwhile, the second side-mounted USB-C port is meant to be used while on PC Mode whereby it’ll boot the device while slowly charging it at the same time. The included USB-C to USB-C is excellent in terms of build quality, feels robust due to the fabric shielding, plus the cable could be bent and according to your liking or use case and stays in that shape till it needs to be readjusted. FYI, Questyle does sell a protective case made with genuine leather for M18i which retails for $29.99 on their official store though I think it might’ve been better if it is included as stock.

Features

Being a dongle that is marketed towards the higher-end market should come with plenty of features, or is it? Under the hood of this M18i is equipped with two of the latest ESS SABRE ES9219Q DAC chip built on a TTA (Three-Tier Architecture) circuitry which is the current flagship DAC chip from ESS SABRE that is capable of decoding up to 32 bit 384kHz for PCMs and DSD256 for DSD formats. Other than that, a Questyle dongle wouldn’t be complete without their patented CMA (Current Mode Amplifier) SiP modules and TOREX semiconductors that are featured in all of their DAC/AMPs even for the most affordable models, the M12i. This allows all Questyle DAC/AMPs to deliver unparalleled audio quality, ultra-low distortion values which Questyle claims to be down to 0.0002% without jeopardizing power efficiency, size and battery performance especially in a battery powered device such as the M18i.

Regarding the power output for the M18i, Questyle does not provide any information about the amount of power or the output impedance through the 3.5mm single-ended at 32 Ohms and 4.4mm balanced at 32 Ohms. However, Questyle does state that the M18i is capable of providing 28mW at 300 Ohms through the 4.4 balanced output and was able to drive in-ear monitors and moderately efficient full-sized headphones optimally without any background noises even when plugged through USB Type-C from my laptop which usually would introduce subtle hissing on other DACs. 

The M18i operates on a 500mAh lithium ion battery which is fairly standard for a small device. There was no information provided about approximately how long the battery lasts and looking in terms of serviceability Nevertheless, users will experience an average 2 hours of music listening while on-the-go which to me is quite an atrocious performance. The M18i runs on several modes which can be toggled by a designated MFB (Multi Function Button) switch that allows you to choose between Mobile Mode, PC Mode and Bluetooth (BT) Mode. On Mobile Mode, the battery could easily last between 2-3 hours which varies across different file formats. Meanwhile, on BT connection the M18i consumes a lot more power resulting in a lower battery performance up to 2 hours and above depending on the Bluetooth codec connected. In this case based on my own finding, enjoying music on LDAC (which up to 96kHz) severely consumes the battery due to the higher bit-rate and processing power needed. On PC Mode, the M18i relies on side-mounted USB connection from the host device which bypasses and charges the battery at the same time implemented via a smart power management feature thus theoretically should slow the wear and tear effect.

Moreover, the M18i is equipped with a 5.4 Bluetooth connection that provides very good coverage up to 35-40 meters (40-45 yards) in indoor areas before experiencing signal drop on Bluetooth LE mode. Meanwhile, on LDAC the BT connection range is slightly lower by a few meters, however it will allow you to enjoy music at the highest bit-rate possible up to 96kHz. Additionally, the M18i could also be used to receive phone calls as it is equipped with Infeneon microphones which are located on the side of the dongle, next to the power button and everything can be accessed via the MFB button. To answer or end a call, press the MFB button once while clicking it twice rejects the call. The microphone quality during calls were quite good and picked up voices quite easily, there was slight compression that could be heard from the receiving end, however I could still hear everything very well without any difficulties.

As far as operating temperature is concerned, the M18i does get slightly warm after a period of use regardless of which modes are selected, however I did notice that the dongle feels slightly warmer when operating on BT Mode with LDAC which is no surprise considering the additional operational power required. Therefore, the M18i can be seen as a compact backup device rather than your main reliance on high quality audio especially if one does not plan to go on a long trip. At some point I do wish that Questyle could have added one or two more features considering the price given at $329 for a dongle because in my opinion the M18i is more of a traditional straightforward PnP (Plug and Play) device. While having the ability to seamlessly receive/answer calls through the dongle controls was handy, I do feel that the M18i are lacking features that audiophiles would tend to use more often such as EQ tools and digital filters.

Specifications

Visual Appearance

Material: CNC Anodized Aluminum Alloy

Color: Black

Size: 75mm x 35mm x 14.5mm

Bluetooth

Version: Ver. 5.4

Supports: AAC, SBC, aptX, aptXHD, aptX adaptive, LDAC, LE Audio

Compatible Operating Systems

Android phones and tablets: Android 5.0 and above

PC: Win10, ver. 1803 and above

Apple: iOS (Requires OTG cable for Lightning to USB-C)

Apple Desktop/Laptops: Mac OS

DAC Capability

PCM: PCM: 44.1kHz-384kHz (16/24/32bit)

DSD: DSD64, DSD128, DSD256

Output Power

4.4mm: 28mW @ 300 ohms

Frequency Response & THD

Frequency Response: ±0.1dB (20Hz-20kHz); ±2dB (20Hz-80kHz)

THD+N: 0.0002%

DAC: (2x) ESS SABRE ES9219Q

Sound Evaluation

Sound evaluation was done by pairing the Questyle M18i with my reference in-ear, Audio Technica ATH-IM02. Alongside other IEMs to see whether there are possible sonic changes or effects caused by the source to my IEMs. Hence, resulting in a shorter narrative compared to my usual sound evaluation to other equipment. This is a purely subjective opinion, based on what I hear and experience as well as my bias. 

Based on my extensive listening with the M18i, the dongle exudes a lively and fairly engaging sound with a minimal warm colouration in the bass and midrange that is unique to Questyle products. The overall presentation was sort of a balanced emphasis on bass and treble but still remained smooth and velvety. Other than that, I hear the M18i to be competent in rendering details, clarity/resolution average at best but there is a grandiose sense of airiness on the upper treble regardless of any pair of in-ear monitors I paired with the M18i.

There is minimal elevation in the bass frequencies that gradually blends into the lower midrange which provides the aforementioned slight warmth sound. I could hear bass slams sounded slightly much softer and polite, with the impact dispersed much more balanced and airy. Each slam felt there’s slightly more depth with slower transients between each bass slam due to the expanded dynamic range from this dongle. Especially with all BA (Balanced Armatures) setup in-ear monitors, such as final B3 and Kiwi Ears Orchestra Lite. However, bass rumbles still remain clean and very much detailed, without coming across as muddy or bloated particularly in the lower midrange.

While I prefer my midrange to be flat and uncoloured. I was not really bothered with the warmer tonality and added richness induced by the M18i, as it adds weight and intimacy in the midrange such as in vocals. Particularly the most obvious one was the sound of acoustic guitars, there’s a bit more heft on lower notes and it lingers due to the wide dynamic range but nevertheless the timbre of the guitar remains unaffected, still sounds very natural and pleasing to my ears. I personally have a high sensitivity towards upper midrange frequencies and I could confirm that M18i does have a slightly emphasized upper midrange which sharpens the forwardness of vocals. That said, this dongle still maintains a refined, smooth upper midrange tuning that provides comfort even for long hours of listening even for my sensitive ears.

Treble is where the M18i feels quite special, although the tuning aims towards vividness. It never feels harsh or peaky like in most dongles, especially in more affordable dongles. It does not feel cramped or claustrophobic, instead you’re immersed in this smooth, wide and airy space. Though I personally appreciate that the M18i has clean, crisp treble, I do think that it is slightly subdued and lacking in brilliance especially for those who prefer a more sparkly, exciting and engaging treble. Therefore, the M18i does fall quite short in terms of its capability to render maximum resolution from high and low level details, despite being excellent at providing detail retrieval. Soundstaging felt vast and spacious especially when paired with an IEM that has an amazing level of dynamic range, this combination is where the M18i truly shines. Spatial imaging appeared to be noticeably sharper, which allows element renderings such as the sound of rolling marbles and balls in Bubbles – Yosi Horikawa sounded much clearer and accurate. 

Synergy Pairing

Shanling TINO

The sound signature of TINO remains unchanged from the original U-shaped tuning with smooth, laid-back treble. I could run the TINO on low gain with barely any effort to achieve the volume level, comfortable for both my casual and critical listening at only 6-8/60. That said, bass slams sounded slightly softer but at the same time gained a noticeable amount of depth with bass rumbles sounds more defined. However, the largest difference was within the upper midrange region whereby I hear vocals appeared to be much softer and less aggressive “in your face” type of intimacy with darker background, compared when plugging with other sources while still maintaining that smoothness and amazing midrange clarity from the small 8mm dynamic driver. The TINO has an airy upper treble and when paired with M18i, I could hear the soundstage has become much wider and much more spherical than oval-ish compared to other dongles. Detail retrieval is improved by a slight amount meanwhile the resolution is average at best, however as a combo that focuses more on musicality and enjoyment rather than precision I truly enjoy the sonic performance from this combination.

Alpha Omega Iota

I was fortunate enough to be able to try pairing the M18i with one of my favourite IEMs back when I first started my audiophile journey almost 6 years ago, the Alpha Omega Iota. Made by the same company that made the Alpha Omega Fulgrim and Alpha Omega – Omega. The Iota is a neutral, reference IEM equipped with 6 BA units that is tuned based on Diffused Field meant for monitoring and professional usage. Right away, I notice there is an obvious amount of warmth being added into the bass frequencies and lower midrange, each bass punch felt meatier, bold yet still rapid, clean and precise. I could feel the rumble has slightly more texture and reach deeper into the lower frequencies. FYI, midrange is the Iota’s main strength. This IEM possesses a neutral, flat lower mid with amazing clarity due to its dark background and strong forward upper midrange unique to DF tuning. The addition of M18i is like adding cherry on the top, elevating it by introducing warmth, intimacy and richness into vocals, instruments and percussion. Moreover, I could also hear the Iota sound much smoother, slightly more laid-back without losing its treble qualities such as treble brilliance/sparkle and airiness that always kept me coming back for more, at the same time soundstaging has slightly become larger and dynamic range was significantly expanded. .

Comparison(s)

Kiwi Ears Allegro Mini

One must be thinking what does a $24 dongle have anything to do with a $349 dongle? In terms of power, the M18i could provide twice or maybe even quadruple the amount of power compared to the Allegro Mini. If we disregard the price difference for a moment, the Allegro Mini has an almost similar kind of warmth and smoothness to the M18i. Except the Allegro Mini was indeed slightly much warmer compared to the M18i, bass slams are more on the boomier side with less depth and even slower transient. Treble is on the peaky side but even less extended to the M18i, the Allegro Mini provides a less airy presentation, much more intimacy and a muted upper treble.  Nevertheless, midrange is where this dongle shines the most, as it is warm, sounds heavier and velvety rich similar to the M18i though I would say the M18i has far greater quality due to the greater clarity especially in rendering vocals, darker background and greater airiness benefit from the treble extension hence creating an intimate sound yet still even less claustrophobic.

Purchasing Links and Where to Get?

• Questyle Official Website (non-affiliated)

Questyle M18i

Conclusion

The Questyle M18i is kind of an odd ball in the dongle segment where it has excellent sonic performance especially from the 4.4mm balanced output, equipped with a decent amount of features which some of it are very useful such as the microphone and voice call controls and but not least an amazing construction quality. Though the dongle is severely disappointed with short battery life unless you’re planning on using it on PC Mode, perhaps Questyle could have made Mobile Mode operate the same as PC Mode where it utilizes battery from the host device to power/charge the dongle like a typical dongle. Other than that, it would be difficult to recommend the M18i for those who would love to enjoy their music with maximum portability especially on BT Mode, especially on LDAC.

Nevertheless, the Questyle M18i is a superb sounding dongle especially for those wanting a lively yet smooth and airy sound signature but at the same time it doesn’t sacrifice detail retrieval from your music. Honestly, at this price point I actually would love to see the emphasis on features that focus on what audiophiles tend to use the most. Such as a bass gain switch for instance the iFi XBass, a software support that allows for EQ (though developing software does mean slightly higher cost) or maybe even digital filters that could be triggered with an additional switch. Because some people would be less likely to consider if the features offered are only occasionally used or never even used, especially when there are other devices to consider at lower prices. However, if pure sound performance is all that ticks the boxes then the Questyle M18i would definitely be worth checking out.