—— Review by "The 3rd Ear Studio," a Chinese audio media
Ten years ago, when Questyle was just establishing its brand, The Third Ear Studio began exploring its products. In recent years, Questyle's brand identity has changed from 'Questyle Audio' to 'Questyle,' marking its transition from primarily focusing on desktop audio products to covering a wide range of portable audio categories. Questyle products have always left a strong impression with their style and quality. Over the past few years, the M15 and M15i in the dongle series have gained a great reputation among users and are among the few products in this category with a long sales cycle.
The newly launched M15C continues many key configurations and features of the M15 series. It still utilizes a current mode amplifier architecture built with two self-developed patented CMA SiP modules, along with Questyle's TOREX precision power management technology. The D/A conversion core has switched from the previously used ESS solution to Cirrus Logic's flagship model CS43198, supporting Hi-Res specifications up to PCM 384 and DSD 256, while maintaining Questyle's consistently impressive low distortion metrics.
The M15C has also received Apple's MFi (Made For iDevices) certification. This certification ensures it can seamlessly connect with Apple devices like iPhones and iPads while meeting strict requirements for power consumption and compatibility. For those who have used early iDevices (such as older iPods with 30-pin Dock or Lightning connectors), the value of MFi certification is very high. As modern iPads and iPhones have standardized on USB-C interface, many users believe that any USB-C device will work with iPads/iPhones. However, in practice, we still encounter issues such as devices not being recognized or system errors caused by power consumption and overheating. Therefore, even though USB-C has become the mainstream interface, Apple's MFi certification requires thorough testing through structural compliance checks, ATS testing, packaging compliance reviews, and other steps to verify the product. This not only ensures basic electrical performance but also maintains strict oversight of brands and companies. Even when users pair MFi-certified products with Android devices, they can still enjoy reliable stability.
As a brand targeting the global market, the M15C is equipped with a multilingual physical user manual, even for its most entry-level product.
In terms of appearance, the M15C features a family-style Bauhaus design, with a body made from CNC-machined aerospace aluminum and a transparent PCB window. The color has shifted from the previous dark tones to silver, and the sandblasted texture is slightly rougher, providing better slip resistance and sweat resistance.
Questyle has always been confident in its PCB layout and craftsmanship, whether in past desktop models or current dongles. Through the transparent window, we can see that the M15C uses the QFN package version of the CS43198 chip from Cirrus Logic, a larger package version of Cirrus Logic's flagship Codec. Compared to non-flagship models, this chip offers better performance, and when compared to the smaller package version of the same model, it typically provides improved heat dissipation and stability in passive cooling scenarios within compact spaces.
For outputs, the M15C offers both 3.5mm single-ended and 4.4mm balanced outputs, plus two adjustable gain settings. Zooming in on the image above, we can see the original Pentaconn 4.4mm output interface, and notice how perfectly the two output interfaces fit into the metal surface, showcasing Questyle's exceptional craftsmanship in hardware.
During our sound experience testing, we primarily paired the M15C with Apple Music on the iPhone 15 Pro Max and iPad as our source. The sound design of the M15C reflects the characteristics of the CS43198 chip while continuing Questyle's tuning philosophy familiar to long-time users.
The CS43198 chip differs from the older flagship CS4398 chip, aligning more closely with the high standards and clean sound quality sought in the new era. Combined with Questyle's TOREX precision power management technology and current mode amplification, the M15C features an ultra-low signal-to-noise ratio, allowing users to confidently pair it with various popular low-impedance, high-sensitivity IEMs. Interestingly, the M15C's voltage output capability even surpasses that of the M15i, providing impressive headroom and dynamic range when used with less demanding over-ear headphones. Additionally, in emergency situations, the M15C can function as a decoder/preamp, allowing direct connection to power amplifiers or active speakers.
During testing, we paired the M15C with new Hi-Res monitoring headphones like the Sony M1. The M15C handled sudden drum hits and strong passages effortlessly. While it may not achieve the exceptional sense of spaciousness and scale of the high-end M15i model, it still delivers a clear and well-separated soundstage overall.
In terms of timbre, Questyle has always excelled at creating a smooth and noble sound impression, and the M15C continues this tradition. Unlike fuller and more passionate tuning styles, the M15C demonstrates superior sound density and detail compared to other products in its price range. While the M15i pursues an extreme focus on detail, the M15C offers a more elegant and bright musical quality, making it versatile and enjoyable across a wide variety of music genres and equipment combinations.
The current market for dongles is showing a polarized trend. Entry-level models typically use standard designs that focus on functionality, offering good basic performance. In contrast, higher-end models in the premium price range are determined to compete with standalone players. In this context, the M15C's positioning is both clever and resolute. With a price set as low as possible, this product achieves solid craftsmanship and objective performance, while its sound tuning reflects the brand's consistent pursuit of quality.
Ten years ago, when Questyle was just establishing its brand, The Third Ear Studio began exploring its products. In recent years, Questyle's brand identity has changed from 'Questyle Audio' to 'Questyle,' marking its transition from primarily focusing on desktop audio products to covering a wide range of portable audio categories. Questyle products have always left a strong impression with their style and quality. Over the past few years, the M15 and M15i in the dongle series have gained a great reputation among users and are among the few products in this category with a long sales cycle.
The newly launched M15C continues many key configurations and features of the M15 series. It still utilizes a current mode amplifier architecture built with two self-developed patented CMA SiP modules, along with Questyle's TOREX precision power management technology. The D/A conversion core has switched from the previously used ESS solution to Cirrus Logic's flagship model CS43198, supporting Hi-Res specifications up to PCM 384 and DSD 256, while maintaining Questyle's consistently impressive low distortion metrics.
The M15C has also received Apple's MFi (Made For iDevices) certification. This certification ensures it can seamlessly connect with Apple devices like iPhones and iPads while meeting strict requirements for power consumption and compatibility. For those who have used early iDevices (such as older iPods with 30-pin Dock or Lightning connectors), the value of MFi certification is very high. As modern iPads and iPhones have standardized on USB-C interface, many users believe that any USB-C device will work with iPads/iPhones. However, in practice, we still encounter issues such as devices not being recognized or system errors caused by power consumption and overheating. Therefore, even though USB-C has become the mainstream interface, Apple's MFi certification requires thorough testing through structural compliance checks, ATS testing, packaging compliance reviews, and other steps to verify the product. This not only ensures basic electrical performance but also maintains strict oversight of brands and companies. Even when users pair MFi-certified products with Android devices, they can still enjoy reliable stability.
As a brand targeting the global market, the M15C is equipped with a multilingual physical user manual, even for its most entry-level product.
In terms of appearance, the M15C features a family-style Bauhaus design, with a body made from CNC-machined aerospace aluminum and a transparent PCB window. The color has shifted from the previous dark tones to silver, and the sandblasted texture is slightly rougher, providing better slip resistance and sweat resistance.
Questyle has always been confident in its PCB layout and craftsmanship, whether in past desktop models or current dongles. Through the transparent window, we can see that the M15C uses the QFN package version of the CS43198 chip from Cirrus Logic, a larger package version of Cirrus Logic's flagship Codec. Compared to non-flagship models, this chip offers better performance, and when compared to the smaller package version of the same model, it typically provides improved heat dissipation and stability in passive cooling scenarios within compact spaces.
For outputs, the M15C offers both 3.5mm single-ended and 4.4mm balanced outputs, plus two adjustable gain settings. Zooming in on the image above, we can see the original Pentaconn 4.4mm output interface, and notice how perfectly the two output interfaces fit into the metal surface, showcasing Questyle's exceptional craftsmanship in hardware.
During our sound experience testing, we primarily paired the M15C with Apple Music on the iPhone 15 Pro Max and iPad as our source. The sound design of the M15C reflects the characteristics of the CS43198 chip while continuing Questyle's tuning philosophy familiar to long-time users.
The CS43198 chip differs from the older flagship CS4398 chip, aligning more closely with the high standards and clean sound quality sought in the new era. Combined with Questyle's TOREX precision power management technology and current mode amplification, the M15C features an ultra-low signal-to-noise ratio, allowing users to confidently pair it with various popular low-impedance, high-sensitivity IEMs. Interestingly, the M15C's voltage output capability even surpasses that of the M15i, providing impressive headroom and dynamic range when used with less demanding over-ear headphones. Additionally, in emergency situations, the M15C can function as a decoder/preamp, allowing direct connection to power amplifiers or active speakers.
During testing, we paired the M15C with new Hi-Res monitoring headphones like the Sony M1. The M15C handled sudden drum hits and strong passages effortlessly. While it may not achieve the exceptional sense of spaciousness and scale of the high-end M15i model, it still delivers a clear and well-separated soundstage overall.
In terms of timbre, Questyle has always excelled at creating a smooth and noble sound impression, and the M15C continues this tradition. Unlike fuller and more passionate tuning styles, the M15C demonstrates superior sound density and detail compared to other products in its price range. While the M15i pursues an extreme focus on detail, the M15C offers a more elegant and bright musical quality, making it versatile and enjoyable across a wide variety of music genres and equipment combinations.
The current market for dongles is showing a polarized trend. Entry-level models typically use standard designs that focus on functionality, offering good basic performance. In contrast, higher-end models in the premium price range are determined to compete with standalone players. In this context, the M15C's positioning is both clever and resolute. With a price set as low as possible, this product achieves solid craftsmanship and objective performance, while its sound tuning reflects the brand's consistent pursuit of quality.
