Nank(Naenka) formally known as Naenka are a Chinese manufacturer specialising in bone conduction headphones.
The Runner Diver 2 are its latest product. As well as Bluetooth (v5.3) support, there's 32GB of memory allowing for music files to be stored on the device itself.
The come in a box (that is remarkably similar dimensions to a competitor) which is mainly cardboard with some plastic inserts to hold various items such as the ear plugs, sound quality enhancers and the headphones themselves. They're also a USB-A charging cable and instruction manual.
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| Headphone box |
If the USB cable is plugged into a PC (macOS or Windows), the headphones appear as a USB disk and music files which are MP3/M4A/WAV/APE/FLAC can be transferred. The headphones support multipoint paring (i.e. multiple devices).
Diver is probably not the best description for the headphones as they are only IP68 certified which is 1 metre depth in water for up to 30 minutes - so maybe Runner Swimmer would be more appropriate. While swimming it's necessary to use the MP3 mode as a Bluetooth connection may cut out when the headphones are submersed and will then try and reconnect as they come out of the water.
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| Looking under headphones |
Bone conduction works by transferring the audio vibrations through the cheekbones so how the headphones fit is quite important. They comes with some silicon inserts called sound enhancers that fit into the ear itself, sitting on the indented bit before the ear canal (so not in the ear canal like in-ear earphones). The sound enhancers come in small, medium and large. The headphones then are placed over the ears.
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| Sound enhancers |
The sound enhancers made a huge difference in sound quality and fit, however head shape has a lot to do with it and they may not make a huge difference for everyone. An obvious issue is that they sit in-front of the ear canal so do block some of the sounds from the environment which is why some people are using bone conduction headphones in the first place. There's good bass, midrange and treble supported by the 16 mm speaker. There's also built-in noise cancelling for the microphones.
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| looking form back |
Battery life is 10 hours (at 60% volume) and 150 hours standby and a full charge takes 1.5 hours and 15 hours talk time. The magnetic connector is polarised so it will only fit one way, but the pins do protrude and can easily short onto any flat metallic material especially if it's ferrous as the magnets will be attracted to it.
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| Side view |
The headphones are reasonably light weight at 32g and are covered in silicone that is skin friendly being soft, hypoallergenic and breathable. The design is meant to resemble a seahorse (well the bone conducting part).
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| Top view |
There are 3 buttons, Power, "+" and "-".
Power button
Long Press 3 secs - Power On / Power Off
Double click - Wake up Voice assistant / exit voice assistant
Click Once - Play/Pause / Answer/Hangup
Double Click - Ignore call
Triple Click - Bluetooth/MP3 mode
Quad (4) clicks - Sequential/Random play in MP3 mode
+ Button
Click once - Volume Up
Long Press 2 seconds - Next song
- Button
Click once - Volume Down
Long Press 2 seconds - Last song
They retail for around £140.00 but a 15% discount is available using the code "Steve" (no quotes required).
As stated without the sound enhancers, the sound quality and fit wasn't brilliant and they vibrated against the skin annoyingly, with the sound enhanced things improved dramatically but that relates to head shape so things might be completely different for other users. With the sound enhancers sound quality was pretty good (as least as good as the competition). Not a bad headphone.
