FiiO M15S Portable High-Resolution Lossless Audio Player with Six Operating Modes and Qualcomm 660

The ‘desktop and portable dual power supply modes’ as featured on the portable desktop-grade player FiiO M17 and the portable desktop-grade amp Q7 have been well-received by the audiophile community, which is why FiiO sought to put this technology on other products. Now, with the implementation of the dual power supply modes onto the M15 with its more ergonomic design, the M15S is the ideal combination of portability and high performance.
Flagship-Level Tech - A New Chapter in the High-End
The new M15S starts a new chapter in the FiO high-end, sharing the same technologies as the portable desktop-grade M17 player and the portable desktop-grade amp Q7 that give you desktop-level performance in a portable package - including desktop mode, dual power supply modes, and five gain levels.
Dedicated Desktop Mode
When in the dedicated desktop mode and under USB fast charging, the M15S will transform essentially into a desktop device and work completely without the battery. That is, under this mode the battery will neither be charged nor discharged, preventing premature battery degradation.
Robust Performance Everywhere
The M15S not only features the ‘desktop and portable dual power supplies’ as seen in other FiiO products but is also equipped with an automatic ‘auxiliary DC power supply’. The M15S is able to automatically recognize when fast charging through USB is being used, and automatically switches to use the highest-voltage power supply, leading to an increase of 26.67 percent in power supply for even more power output. Even when not using the fast-charging adapter, the M15S can still automatically switch to a higher-voltage power supply that is enough to drive most headphones.
Near-Desktop Power
The M15S can be adjusted with five levels of gain. Under battery power, low, medium, high, and over-ear headphone gain levels can be selected. When under USB power, the enhanced over-ear headphone gain level is also available, enabling undistorted power output up to 1200 mW per channel, easily enough to drive a wide variety of IEMs and headphones.
Six Operating Modes Including Roon Ready
Firstly, there is Pure Music mode, a FiiO-exclusive mode, for immersive music. Second is Android mode which freely uses third-party apps, including those of streaming services. Next is AirPlay mode wirelessly connect to iOS devices like iPhone or iPad, with a sound quality boost. Fourth is Roon Ready mode which is Roon Ready certified, for serious music lovers. Fifth is USB DAC mode which acts as a DAC when connected to a computer or phone, for greatly improved sound. Finally, there is the Bluetooth Receiver mode that supports SBC, AAC, aptX, aptx HD, aptx LL, LDAC, and apt Adaptive, for convenient quality wireless sound.
Overbuilt Power Supply for Ample Clean Power Anytime
Fully separated digital power supply, effectively reducing crosstalk, and interference. Multi-stage analog power supply, high-precision, and low noise for early signal processing. Multi-voltage servo power supply for headphone amp, capably driving low and high-impedance loads.
High-Performance ES9038PRO DAC Desktop-Grade Part
The full, uncut desktop ES9038PRO DAC chip with eight independent D and A converters is employed in the M15S. Each channel uses four D and A converters in parallel to form a fully differential output, for a truly rich and highly resolving sound.
4th-Gen FPGA with NDK Femtosecond Crystal DAPS Digital Audio Purification System
Audio data is passed through a FiiO-developed 4th-gen FPGA with phase-locked loop technology, which works together with two custom Japanese NDK femtosecond crystal oscillators to provide a high-precision and low-jitter unified clock source for the entire audio architecture. This is all done in the pursuit of purer sound.
Multi-Stage Audio Circuit for Faithful Sound Reproduction
The M15S features a multi-stage audio circuit complete with IV, LPF, gain adjustment, and amplifier sections. High-precision and low-noise film resistor used ensures more accurate signal reproduction and channel balance. Within the LPF part of the circuit are Panasonic low-loss metalized film capacitors that guarantee extremely low harmonic and phase distortion.
Graphene Heat Dissipation Technology Cooling for Consistent High-Power Output
Advanced and highly efficient heat dissipation design allows the M15S to maintain stable temperatures and continuously deliver high power output with a stainless steel battery compartment, to quickly dissipate battery heat. Next is a low temperature-drift and high-precision thin-film resistors and capacitors, that can stably cope with temperature swings. Finally, there is a dedicated metal shield, graphene, and high thermal conductivity silica gel over hotspots for maximum heat dissipation.
Comprehensive Shielding for Truly ‘Clean’ Sound
In order to shield from interference as much as possible, the M15S employs a nickel-copper shield that shields the analog portion of the audio circuit as well as the main SoC to ensure the purity of the analog signals traveling through the circuit. In addition, stacked onto the main shield are other heat dissipation and shielding materials as well as wave-absorbing paper. The high-quality parts and carefully considered shielding design all aim to ensure truly clean and highly-resolved sound.