Fiio BTR15 review: This Bluetooth DAC is the ultimate value

Fiio sells products in about a dozen categories, but it's the brand's budget DACs and IEMs that contribute to its bottom line in a meaningful way. There has been a lot of excitement in this area in recent months, with Fiio launching a lot of new models in its dongle DAC range, and the brand is now focusing on its Bluetooth offerings.

While the KA11 and KA13 do a great job delivering a clean sound in a tiny chassis, they need to be plugged in — you don't get Bluetooth connectivity. Thankfully, the brand has the BTR5 and BTR7 if you want Bluetooth DACs, and both are highly regarded; I use the BTR7 extensively. And now, there's a new entrant in this segment: the BTR15.

Although the naming convention suggests the BTR15 should be the flagship offering, it is an updated model of the BTR5 that has a ton of enticing features. It shares the same design as the BTR5, but you get a larger OLED panel, updated Bluetooth modem with Bluetooth 5.1, and the ability to deliver up to 340mW of power, which is more than the BTR7.

The best part? The BTR15 retails for just $109, which is lower than the launch price of the BTR5.

Fiio BTR15: Pricing and availability

Fiio launched the BTR15 back in October 2023, and the DAC is now available globally. Over in the U.S., the DAC is available for $109 on Amazon, and you can pick it up from a variety of audio retailers. The DAC costs £114 in the U.K., and in India, it is available for ₹9,999 ($120).

Fiio BTR15: What I like

Fiio really doesn't like changing the design of its products between generations, and as a result, the BTR15 shares a lot of design similarities to the BTR5. Both have the same aesthetic with dual curved sides — similar to what you get on the best Android phones — and there's glass coating the front and back panels.

The rest of the chassis is constructed out of aluminum, and the build quality is exquisite. The design itself is rather elegant, and it gives the BTR15 a sense of refinement that belies its price tag. I used the DAC for the better part of three months, and I didn't see any issues with the build quality.

Coming in at 37.3g, the BTR15 is small enough that you can just carry it in your pocket, and the diminutive size makes it a great choice. It is a smidgen narrower and thicker than the BTR5, but other than that, the design is fundamentally unchanged.

You get all the buttons on the right, and there is a lot to cover. There's the power button, multifunction button, volume rocker, and a toggle that lets you switch between Bluetooth, PC, and phone modes. The buttons are tiny, but they have good tactile feedback.

All the connectivity you need

The key difference over the BTR5 is that the BTR15 has a 4.4mm port alongside the standard 3.5mm port. The BTR5 had a 2.5mm port for the balanced connection, but with the inclusion of a 4.4mm port, you can use the BTR15 with a significantly wider range of products, including headsets.

You can connect the BTR15 with your phone via Bluetooth or USB-C, and the DAC uses Qualcomm's QCC5125 modem, offering Bluetooth 5.1 connectivity. This is the same modem that's used in costlier DACs like the Q15 and K9, so it's great to see Fiio bringing it to a budget product.

In addition to greater range, the QCC5125 unlocks high-res audio codecs; you get LDAC along with the full suite of AptX codecs, including AptX, AptX LL, AptX Adaptive, and AptX HD. The BTR15 has a 550mAh battery, and it lasts just over six hours in LDAC mode.

Another major difference is the screen; the BTR15 has a larger 0.96-inch OLED panel, and it has higher contrast text, making it easy to read outdoors. You can use the screen to navigate the settings, including adjusting the gain, tweaking the EQ, switching to the built-in car mode, and a whole lot more. You can also use the Fiio Control app to change all the setting.

The default screen shows the mode currently in use, volume level, gain, and battery indicator. The screen gives the BTR15 a distinct edge over the KA series of dongle DACs.

Outstanding sound

The BTR15 features dual ESS ES9219MQ DACs, and the USB side of things is handled by an XMOS XU316. It goes up to 384kHz/32-bit over PCM and has DSD256, but it's the power on offer that makes it stand out against the BTR5 and even the BTR7.

The BTR15 manages to deliver 165mW of power at 16Ω and 125mW at 32Ω over the 3.5mm port, and it goes up to 270mW at 16Ω and 340mW at 32Ω when using the balanced 4.4mm port. It is more powerful than the BTR7 in this regard, and it is able to drive just about any IEM in the market, as well as planar headsets like the FT5.

Coming to the sound, the BTR15 has the same clean sound that's a characteristic of the brand's budget DACs, and you get a slight hint of warmth that makes using it enjoyable. I tested the DAC with the Fiio FX15 and FT5, and both proved to be good pairings; the BTR15 was able to deliver a vibrant bass with good texture, unlocking the potential of the FX15. The mid-range is natural and has plenty of clarity, with vocals coming through with good articulation.

The treble is detailed and airy, and the biggest difference between the BTR5 is that the BTR15 has better resolution overall.

Fiio BTR15: What I didn't like

There really isn't much to criticize with the BTR15. The only quibble I have with the design is that the glass panels tend to smudge easily, and the back is prone to scratches if you carry it around in your pocket. This can be mitigated by using the bundled clear case.

The BTR5 had a nifty option to use NFC to connect to phones easily, and that's missing on the BTR15. It isn't a huge omission by itself, but it was a cool feature. Also, you don't get a USB-C to Lightning cable in the box any longer; with the iPhone 15 models switching over to USB-C, Fiio has decided to bundle just a USB-C cable and a USB-A dongle in the package, so if you're using an older iPhone, you will need to source a small USB-C to Lightning cable.

There's no fast charging, so even though the BTR15 has a small 550mAh battery, it takes nearly two hours to charge the DAC. My Magic 6 Pro has a battery that's nearly ten times larger, and it takes just under an hour to charge. Obviously, the BTR15 is designed to be used for much longer than a phone, and it makes sense that Fiio wants to prolong battery life, but fast charging of up to 10W would have made a difference — right now, it only goes up to 5W. 

Fiio BTR15: Should you buy it?

You should buy this if:

• You need a Bluetooth DAC with plenty of power
• You need a balanced 4.4mm port
• You want good battery life
• You need a DAC that's easily pocketable

You shouldn't buy this if:

• You want fast charging

Having switched to the BTR15 from the BTR5 and BTR7, it's easy to tell that Fiio is onto a winner. The DAC delivers a clean sound and retains a lot of the same tonal characteristics as the BTR7, and the increased power on offer makes it a better choice if you're interested in a Bluetooth DAC to use with a headset.

Then there's the value to consider. At $109, the BTR15 is the best value in the brand's DAC portfolio as of writing. It manages to outmatch the BTR5 considerably, and has notable wins against the costlier BTR7, and that's no small feat.