FiiO BTR15 Review

FiiO BTR15 Review

FiiO BTR15 Review – Swiss Army Knife of Portable Audio

The FiiO BTR5 series has dominated the market for Bluetooth DAC-AMPs in its price range since it was launched in 2019. Now, the enhanced BTR15 model offers a lighter and more powerful design, promising an improved user and listening experience.

FiiO BTR15 Review

FiiO’s BTR15 features hot-bent curved glass on both the front and rear, a first for the brand. This unique design not only enhances grip but also reduces weight by 6.4g compared to the BTR5. Combined with the aluminum alloy middle frame, the BTR15 offers a comfortable handling experience.

FiiO BTR15 Review

From the users’ point of view, FiiO’s engineers have designed the BTR15 with a one-toggle switch between PC/BT/PHONE, which allows a quick switch to the corresponding working mode. In the PC mode, the device is completely powered by the computer, while in the BT/PHONE mode, the device is powered by the internal battery.

  • PC mode: The BTR15 will enter the USB decoding mode for desktop devices and can be powered through USB.
  • BT mode: The BTR15 will enter the Bluetooth receiving mode and can be powered through USB.
  • PHONE mode: The BTR15 will enter the decoding mode for mobile -phones and will be disabled from USB charging (The device will be forced to charge if it is powered off for low battery).

The multifunction button is for reconnecting Bluetooth, play, pause, answer/hang up/cancel a call, force a pairing, activate voice assistant, and confirming the menu.

FiiO BTR15 Review
When connecting through Bluetooth or USB DAC, the BTR15 supports 60 levels of volume adjustment.

The BTR15 has a big screen, a 0.96-inch OLED display. This screen not only shows more information at once, but it also has bigger fonts, making it easier for you to see the device status and adjust different settings. Additionally, it is a unique device that supports both Chinese and English languages, which is not commonly found in similar products.

FiiO BTR15 Review

In addition to the standard 3.5mm single-ended headphone output, the BTR15 also comes with the widely-used 4.4mm balanced headphone output. Thanks to the new internal design, the output power has been completely improved.

FiiO BTR15 Review

With this in mind, FiiO engineers have designed an independent power supply for the headphone amplifier section of the ES9219MQ. This results in purer and more robust power for the headphone amp. Compared to the BTR5, the BTR15 has a 40% increase in output power to 340mW in balanced output and a 56% increase of output power to 125mW in single-ended output.

FiiO BTR15 Review

The BTR15 employs the high-performance combination of the Qualcomm QCC5125 Bluetooth chip + XMOS 16-core XU316 that supports stable high-res audio playback in any mode. The BT mode supports all Hi-Res Bluetooth codecs with sampling rates up to 96kHz, and PC/PHONE modes support decoding up to 384kHz/32bit PCM and DSD256 and MQA Full Decoder.

FiiO BTR15 Review

The BTR15 features a global parametric equalizer (PEQ). Through FiiO’s self-developed PEQ algorithm and user interface, in any mode, you can choose the exact frequencies to be adjusted along with their gain levels and bandwidth, allowing you to fine-tune the sound to exactly the way you want it.

BTR15 Settings Menu

Car Mode: When the vehicle engine starts, the BTR15 will power on automatically, and power off when the engine stops.

FiiO Control App

What’s included

  • BTR15
  • Type-C to Type-C cable
  • USB adapter
  • Removable back clip
  • Quick start guide
  • Warranty card


  • Bluetooth chip: QCC5125 (CPU+DSP dual-core architecture)
  • Bluetooth version: 5.1
  • USB chip: XMOS XU316
  • DAC: ES9219MQ x 2
  • Bluetooth codecs: AAC/SBC/aptX/aptX LL/aptX Adaptive/aptX HD/LDAC
  • USB DAC: Asynchronous 384kHz-32bit, DSD256
  • USB DAC driver-free mode: Supported
  • Display: 0.96-inch 96×96 resolution OLED
  • Headphone outs: Single-ended 3.5mm + Balanced 4.4mm
  • Dimensions: About 32.0mm x 72.2mm × 12.5mm
  • Weight: About 37.3g
  • Charging time: < 2h
  • Battery: 550mAh high-temperature resistant lithium-ion
  • Battery life: About 8 hours
  • Output power 1: L+ R ≥ 125 mW+125mW (32Ω single-ended /THD+N < 1 %)
  • Output power 2: L+ R > 15 mW+ 15 mW (300Ω single-ended /THD+N < 1%)
  • Output power 3: L+R≥ 340mW + 340mW (32Ω balanced/THD+N< 1%)
  • Output power 4: L+R≥ 50mW+ 50mW (300Ω balanced/THD+N < 1%)
  • Frequency response: 20Hz~50kHz (-0.8dB)
  • Signal-to-noise ratio: >122dB (A-weighted)
  • Noise floor: PO <2 uV (A-weighted); BAL < 2.7 uV (A-weighted)
  • Price: $109.99

I would like to thank FiiO for providing me with the review sample of the BTR15.


The FiiO BTR15 offers a balanced sound profile, with a neutral signature. It delivers a good amount of dynamics, layering, and texture across the entire frequency range.

The BTR15 has impressive lows that are both deep and quick. It is well-managed and offers excellent extension and texture. The midbass is well handled, providing a clear definition. It doesn’t overpower the other elements and remains clean. As a result, vocals and instruments sound exceptionally clean and neutral. The BTR15 also delivers good clarity with a natural tonality.

FiiO BTR15 Review

Midrange has strong attack and dynamics, along with excellent transparency. The tonality is accurate and neutral, without any added coloration. The BTR15 delivers a neutral and linear sound on mids, which I found very appealing.

The FiiO BTR15 offers a dynamic and immersive audio experience right from the start. The instruments sound realistic, creating a rich and full sound quality.

FiiO BTR15 Review

The high notes are crisp, yet not too harsh, and they extend well. It is not overly emphasized either with a clean but not aggressive overtone and very little in the way of distracting upper-mids sharpness. The highs are defined with a clear and airy attack and a good timbre. 

The FiiO BTR15 provides ample air and space between instruments and vocals, resulting in a satisfying level of separation and soundstage. Its tonality is natural and free from any artificial enhancements. The sound is neither warm nor bright, but rather accurate. If you’re looking for a device that strikes a balance between musicality and technicality, the FiiO BTR15 excels in delivering just that.

FiiO BTR15 Review 20 1
BTR15 can drive the planar headphone FT5 in high gain mode around %35-40 of volume.


The FiiO BTR15 is equipped with everything you need. It features the flagship USB controller XMOS XU316, which is a first for a dongle DAC (the new KA17 also has it). It also has a global PEQ that works with both Bluetooth and USB, and its sound performance is comparable to models like the FiiO KA5 dongle DAC in the same price range. Additionally, it offers full MQA decoding support. The BTR15 is like a Swiss Knife that every hardcore audiophile or newcomer to the hobby should have in their pockets.