This is a review of the Fiio BTR3 Hi-Res audio Bluetooth amplifier and USB DAC
Why do we need high-resolution audio playback anyway?…
There are some who say that hi-res audio is a bit of a myth, in that if you can’t physically hear it, then you’re just adding data that is unnecessary. Then there are others who believe that you can never have a high-enough sample rate to get the ultimate transient response.
I would have to say my opinion lies somewhere in the middle.
Back around 2012, I purchased my first Focusrite Scarlett 2i4 audio interface, which allows recording up to 96KHz, which I then started using for event recordings. This showed me (or more specifically allowed me to hear) the difference between 48k & 96k when recording DJ’s playing both CDs and Vinyl (which is a whole different argument for another time!). In short, it does make a difference in the reproduction of the transients.
For anyone who doesn’t know what transient response is – a square wave is made up of a series of sine waves of increasing (harmonic) frequency, so a ‘perfect’ square wave would have an infinite number of harmonics to be perfectly reproduced. In this context, a higher sample rate allows your hypothetical square wave to be more ‘square’ by capturing more of those higher frequencies that act as part of the initial signal (the transient being the leading edge of the square). So even when these frequencies are beyond the range of human hearing, it’s generally accepted that they can affect the reproduction of those that are…
What’s wrong with audio over Bluetooth?…
Historically, Bluetooth audio has been pretty low bitrate, using the A2DP profile which only allows for compressed codecs like MP3, AAC & ATRAC. So for anyone wanting high-quality audio, you needed wired headphones.
How can we make this better?…
When I upgraded to a Sony Xperia 1 phone (it worked out that it only added £5 to my monthly contract), based on the videography credentials, I had to deal with it not having a physical headphone jack. Instead, there was the included USB-C to minijack adaptor, which for me seemed like a really bad idea, as you know at some point that’s likely to break or damage the socket leaving the device unable to charge.
I already had a Fiio E17K USB DAC for my work desktop (a Dell machine that surprisingly had an optical audio output) which sounded great. So I then discovered the Fiio BTR3 that would give me the sound quality I was after, without either trailing cables from an add-on device – the E17K also works with mobile devices over USB, but it’s a bit bulky for that – and also allow me to use my own earbuds that I’ve replaced about 3 times with the same (or newer equivalent) models. These being currently the Sony MDR-EX450 – the closest thing I’ve found to listening on my studio monitors. So how could I achieve high-resolution audio without wires I hear you ask?…
Presenting the Fiio Portable High-Fidelity Bluetooth Amplifier-BTR3!
I did search for other potential solutions, but this was the one I chose.
The Sony Xperia 1 is branded as having Hi-Res audio capabilities and circuitry based on their (somewhat overpriced) standalone audio players, plus it supports the APT-X and LDAC codecs for audio over Bluetooth. Which the BTR3 also supports perfectly.
It’s about the size of a finger, lasts for about 11 hours of playback, has playback and call buttons and charges over a USB-C connector, so in matching it with my phone, I only need one charging cable.
There’s an in-built mic, so it works as a standard wireless headset (although you can’t have hi-res audio and a two-way connection, so that switches back to standard Bluetooth audio).
It also features NFC pairing and with appropriate drivers, can work as a USB(-C) DAC in your computer. So if you commute into a busy office, you could theoretically go all day without having to directly hear another person! Although that might make your earbuds a bit icky after a while.
| Model | BTR3 | Color Available | Black/Red |
| Weight | About 26 g (incl. battery) | Dimensions | About 58×25×10.4mm (exclusive of back clip) |
| Audio Input | Bluetooth connection (Bluetooth 4.2 supported) | Supported Audio Format(s) | AAC/SBC/aptX/aptX LL/ aptX HD/LDAC/LHDC |
| NFC | Supported | Mic Function | Supported |
| Headphone Output | 3.5 mm stereo jack | USB Port | Type C USB |
| Volume Control | Side buttons | Status Indicator Light | RGB light indicates the input Bluetooth audio codec, charging and working status |
| Charging Time | ≤1.5 h (DC 5V 500mA) | Power Input | Recommend DC 5V, 500mA |
| Battery Capacity | 300 mAh | Drive Ability | 16~100 Ω (recommended) |
| Output Power | About 25mW (32Ω loaded)
About 33mW (16Ω loaded) |
Frequency Response | 20～20kHz（aptX connection)
20～40kHz（LDAC connection) |
| THD+N | ＜0.003%(LHDC 1kHz) | Output Impedance | ＜0.3 Ω（32Ω loaded） |
| SNR | 120dB (A-weighted) | Crosstalk | ≥ 75 dB（32Ω loaded） |
| Bluetooth Chip | CSR8675 | Accessories | Type C USB charging cable*1, Quick Start Guide*1, Warranty Card*1, Lanyard*1 |
What’s it actually like?…
In use, it’s great. It accurately reproduces the high-res audio files I have, allowing me to ‘hear into’ the detail of whatever I’m listening to. It allows me to use my own earbuds, which I can leave attached and just wrap up into my pocket. On the rare occasions that I actually have to answer a phone call when I’m out and about, I can do so without getting my phone out of my pocket.
Plus, it’s not a massive set of over-ear, expensive headphones that are likely to get lost, stolen or sat on and broken.
All in all, to paraphrase Wolverine from the X-men “it’s the best at what it does”.
Available from amazon.co.uk for £44.99