Questyle M15i Portable Hi-Res USB DAC & Headphone Amplifier

The Questyle M15i is a high-performance portable USB DAC and headphone amplifier designed for audiophiles who demand uncompromising sound quality from mobile devices. Featuring Questyle’s patented Current Mode Amplification, a flagship ESS DAC, and both single-ended and balanced outputs, the M15i delivers exceptional clarity, speed, and realism in a compact, travel-friendly form factor.

Whether you are listening from a smartphone, tablet, or laptop, the Questyle M15i transforms everyday digital audio into a true high-resolution listening experience, driving everything from sensitive in-ear monitors to high-impedance headphones with authority and finesse.

Key Features

• ESS ES9281AC High-Resolution DAC
  Supports ultra-high-resolution audio playback up to 32-bit / 768kHz PCM and native DSD512, preserving every detail of your music.
• Questyle Current Mode Amplification Technology
  Quad-core current-mode amplification architecture delivers extremely low distortion, fast transient response, and a pitch-black noise floor for reference-grade sound.
• Balanced and Single-Ended Outputs
  Equipped with both 4.4mm balanced and 3.5mm single-ended headphone outputs for maximum compatibility and improved channel separation.
• Manual Gain Control
  High and Low gain settings allow optimal matching with both ultra-sensitive IEMs and power-hungry full-size headphones.
• High-Power Portable Performance
  Clean, stable output power with excellent control across a wide range of headphone impedances.
• Dynamic Sampling Rate Indicator
  Built-in visual indicator displays real-time sampling rate and DSD playback status.
• Wide Device Compatibility
  Plug-and-play support for Android, iOS (with adapter), Windows, and macOS devices with no drivers required.
• Premium CNC Aluminum Construction
  Precision-machined aluminum alloy chassis provides durability, heat dissipation, and a refined minimalist aesthetic.

Technical Specifications

DAC Chipset
ESS ES9281AC

Audio Format Support
PCM: 44.1kHz – 768kHz (16 / 24 / 32-bit)
DSD: DSD64 / DSD128 / DSD256 / DSD512 (Native)

Headphone Outputs
3.5mm single-ended
4.4mm balanced

Output Power
3.5mm: 11.97 mW @ 300Ω
4.4mm: 22.60 mW @ 300Ω

Frequency Response
20Hz – 20kHz (±0.1dB)
20Hz – 80kHz (±2dB)

Total Harmonic Distortion + Noise
0.0003%

Gain Settings
High / Low manual gain switch

Compatibility
Android, iOS (with adapter), Windows, macOS

Chassis Material
CNC-machined anodized aluminum alloy

Dimensions
61.9 × 27.9 × 12 mm

Included Accessories
USB-C to USB-C cable
USB-C to USB-A cable
User manual and warranty card

Why Choose the Questyle M15i?

The Questyle M15i portable DAC and headphone amplifier stands out by combining desktop-class audio performance with true mobile convenience. Its current-mode amplification technology, balanced output design, and high-resolution decoding capabilities make it an ideal upgrade for audiophiles seeking transparent, powerful, and musical sound on the go.

Perfect for high-end headphones, premium IEMs, and lossless streaming services, the Questyle M15i delivers reference-quality sound from your pocket.