Call Quality And Audio Performance
Our experience with using the One as an actual phone was mixed. When it first launched, call quality was quite poor and there were volume issues. These were software related, so updates to the One have addressed most of the problems, making calls sound a lot better. The One also has three microphones for its noise-cancelling technology, and we were told that our voice did come through nice and clear when we used the phone.
However, while the actual in-call quality is now quite good, the One does still have some problems with cellular reception. For example, in our tester’s home in the middle of the large city of Toronto, the One often dropped to one or two bars in places that other phones had full reception. We also found that it sometimes dropped from LTE to HSPA data and wouldn’t go back to LTE unless you rebooted the phone. These issues are most likely software related, rather than unfixable hardware problems, but obviously shouldn’t be occurring. Also, these issues are based on our experience using the One on only one carrier network, Canada’s Telus, so users on other networks might not face the same issues.
In a recent software update (CM 11S 38R), OnePlus enhanced its audio playback capabilities by adding support for high-resolution music. The One can now play 24-bit, 96/192khz flac/alac/wav files without resampling. This upgrade lines up nicely with its announcement of the new OnePlus branded JBL in-ear headphones, shown above.
To test the One’s audio quality, we played some classical music in a 24-bit, 192kHz flac format. The One’s speakers played nice and loud, but were a little thin sounding and distorted at maximum volume. A YouTube music video also played back nice and loud, but again there wasn’t much bass and it distorted at high volumes. While you can use the included Audio FX EQ application to improve the sound quality when using the speakers, it doesn’t make a huge difference to the overall quality.
Even though there are two speakers, they are so close to each other that there is no stereo effect at all. Also, since they are bottom-facing, when the phone is held in landscape mode it is clear that the audio is only coming from one side of the phone. There is also the problem of your hand muffling the sound when holding the One in two hands, like when gaming. With the amount of bezel space above and below the screen, it would have been nice if OnePlus could have incorporated front-facing stereo speakers like the HTC One (M8) and Xperia Z3.
In contrast to the poor performance of the external speakers, when using a good set of headphones, like the SteelSeries 9H’s we tested the One with, there is a huge improvement in audio quality. In fact, we’d have to say the same audio tests using the flac audio file and YouTube videos sounded exceptionally good when using headphones. While we are not sure of the specific audio hardware in the One, it is clearly a step above what is found in many other smartphones. As when using the speakers, you can use the Audio FX EQ application to tweak the audio, and even add a simulated surround sound effect to whatever you are listening to.