Sound Quality - Wired or Bluetooth?
(Picture credit: https://www.unsplash.com)
In recent years, it has been increasingly popular to use Bluetooth headphones, earbuds and In-Ear Monitors (IEMs) to listen to music. Therefore a common question asked by music enthusiasts is if there is a noticeable difference in sound quality between wired and Bluetooth gear.
In this article, let’s delve deeper into this topic and attempt to answer these questions - What do we offset in the name of convenience? Does wired really sound better than Bluetooth? We have to first understand the main differences as to how wired and Bluetooth headphones reach their intended sound signature.
Wired Headphones
ISK MDH9000 Headphones (Picture credit: https://www.oardio.com)
Wired headphones (including earbuds and IEMs) are engineered (in terms of drivers and acoustics) to sound great out of the box. They take an analog audio signal from your phone or laptop and present it directly to you. The quality of the audio signal that reaches the headphones can obviously affect how well they sound, but all of that happens outside of the headphones.
How does Bluetooth work?
Bluetooth headphones, on the other hand, require many more engineering decisions to be made. Bluetooth audio is packed as digital data, so all of the processing happens within the headphones. There are a few main obstacles that Bluetooth headphones need to tackle in order to potentially be on par with analog wired headphones:
1. Lossless Audio Files
This is something that not everyone will be able to relate to – Most audiophiles will pick this up easily, whilst the masses won’t be able to hear a noticeable aural difference. Bluetooth audio has a hard limit on the resolution and sample rate of the audio it can process. Bluetooth codecs (that encode and decode digital audio data) can handle MP3 (compressed at 320kbps) with relative ease and even manage to take advantage of higher quality lossless audio files but it is still not possible to successfully transfer every bit and sample of most lossless audio files.
2. Reliability
Compared to a properly shielded cable, Bluetooth stream is less reliable. The data your Bluetooth headphones receive will rarely be exactly as what your device sends out, hence samples getting missing or misplaced happens commonly. Whilst cables are also rarely perfect (that’s another whole new topic to talk about), the effect of any degradation caused by cables under normal circumstances is much less audible than the damage done by Bluetooth streams.
3. Digital to Analog Conversion (DAC)
When the audio stream reaches your Bluetooth headphones, it still exists as digital data. So for you to hear sound (analog), the DAC process has to occur within your headphones. Comparing that to wired headphones where your phone or laptop already does the conversion, it’s hard to expect the same performance and clarity when Bluetooth headphones have to house a DAC within them.
4. Cost
All the additional electronics and engineering we talked about in earlier points increase the cost of a Bluetooth headphone significantly. Manufacturers have decisions to make when it comes to delivering a good balance of cost and performance/quality. Cost is an important considering factor to the masses, so what Bluetooth headphone manufacturers often decide to do is to cut costs on components and properly tuning the headphones.
Bluetooth Isn’t for Everyone
Apple AirPods
Bluetooth headphones and earphones like the Apple AirPods may be good enough for most people, but it’s not good enough for everyone. For most average consumers, Bluetooth is perfectly fine, especially with improving Bluetooth technology in more recent times. But for the more critical listeners and music enthusiasts, those limitations will come to show.
In conclusion, you can see that Bluetooth isn't simply an alternative for a wire, it requires a lot of difficult tasks to be overcome inside the headphones. The trade-off you have to make for wanting a full audio setup in a tiny form factor without any wires is simply the fact that Bluetooth headphones have less potential to sound as good as wired headphones. In my personal opinion, it is possible engineer a great set of Bluetooth headphones that rivals professional wired headphones. The question is – at what cost? What’s the cost multiple you would be willing to pay for a set of Bluetooth headphones that have the same audio quality as the wired option?
Something to Consider
Good news! If you absolutely love your earbuds or IEMs but want that extra convenience occasionally when you are out and about, there are Bluetooth adapter cables out there to consider.
For example, the KZ APTX-HD Bluetooth Module 5.0 Upgrade cable works for the KZ AS10/AS06/BA10/ZST/ZS10/ZSR/ES4 CCA C16/C10 or any earphone of a similar model.
KZ APTX-HD Bluetooth Module 5.0 (Picture credit: https://www.oardio.com)