For over six months there have been strong rumours that Apple will drop the 3.5mm headphone jack in the next iPhone, something that may have a large impact on the market of portable headphones. Either they will have to adopt the proprietary Lightning connector, or use the more standard Bluetooth wireless protocol.
This isn't too surprising. I've noticed that with the latest Apple TV, the entirety of the Apple product line supports Bluetooth headphones, as if to prepare the market for a more "wireless" headphone future.
Still, if that were to happen, it would suck. And I'm not the only one to preemptively complain. I've avoided wireless headphones since they used to greatly reduce the sound quality, on top of the inconveniences of limited range and batteries that need recharge.
Unrelated to this Apple rumour, I did try out wireless headphones (of many kinds). So, are wireless headphones in 2016 good enough?
My first pair of wireless headphones is the Sennheiser RS 175. It is made for home use, as it requires a wireless base that also acts as a charging station for the headphones. It is using some kind of digital connection (up to 96 kHz PCM at source, and using 8-FSK digital lossless), so you either get the full quality or none at all, unlike analogue signals that would degrade the source quality depending on the interference. For me, the primary use for those headphones was to use them at home with some freedom of movement that wired headphones wouldn't permit, and also to not have wires on the middle of the living room anymore. I was pleasantly surprised at the sound quality and how long the battery charge lasts.
Yet, those avoided my main concerns about Bluetooth headphones: Is the sound quality allowed by the Bluetooth protocol good enough? Some background about Bluetooth audio protocols first.
The first kind of audio supported by Bluetooth was for phone calls, so the audio quality targets what is typically needed for phone lines and not much more. This was done through the Headset Profile (HSP) for headsets, and the Hands-Free Profile (HFP) for cars. Both support 64 kbit/s signals, be it uncompressed, µ-law or a-law, commonly used in telephony, or CVSDM. For music, this is pretty bad, and I suspect my early experiences with music over Bluetooth was through those profiles.
Later, Bluetooth supported "proper" music streaming though the Advanced Audio Distribution Profile (A2DP). While it can support modern MPEG audio codecs (MP3, AAC, etc.), the only required codec is SBC, the only one that was available for free for use in Bluetooth applications. There's also the newer and better aptX, but most devices don't support it, notably all iPhones, maybe due to licensing costs and patent protections. And since MPEG codecs are even more expensive to license, it means the only codec commonly supported is SBC. And how good is SBC? Well, good enough compared to other codecs at that bit rate. In plain English, you can hear some quality loss if you listen hard enough. The quality loss is comparable to 256 kbit/s MP3s, which is fine but not great.
So, before jumping into Bluetooth headphones, I tested out Bluetooth audio with two different portable Bluetooth receivers. The first is the OT-ADAPT, made for outdoor sporting, where you would place your phone in your backpack and use a standard set of headphones connected to the receiver outside. The second is the MPOW, this time made for car stereos, but portable enough to be used outdoors. What I noticed with both is that the audio quality is far more impacted by the quality of the DAC than the SBC codec in the first place. The MPOW is generally louder than the OT-ADAPT (since it typically targets "audio line in" at full volume), but even at comparable volume it has far fewer background noise in the output signal. Still, with either receivers, the sound quality loss cannot be noticed with any sub-$100 headphones at average volume.
And then I finally made the jump to Bluetooth-enabled headphones, with the Sennheiser Momentum M2 AEBT. Testing with the provided cables with wired "airplane mode" use, I noticed no quality difference between wired and Bluetooth wireless audio, even while using SBC with my iPhone (the M2 does support aptX). The price difference for the premium of having Bluetooth is difficult to justify compared to sub-$30 Bluetooth receivers, but then those headphones have amazing sound quality and reasonable active noise cancellation.
So, what's my recommendation? If you simply want some freedom of movement or Bluetooth-enable your car's audio system, the MPOW Bluetooth receiver should be good enough. Otherwise, you may want to wait for a few months, as the release of the next headphone jack-free iPhone may spur a new wave of Bluetooth headphones, driving down the price of older models. And don't worry too much about sound quality: It's good enough.
Published on July 7, 2016 at 18:44 EDT
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