Why is Bluetooth Audio Quality So Bad? (Explained)

We like the idea of wireless audio. However, the convenience of Bluetooth audio comes at a cost while compromising the sound quality.

bluetooth audio quality

Due to the peace of mind that comes with maintaining a quality listening experience, many audiophiles refrain from removing all those long and tangled wires. 

So, why is Bluetooth audio quality so bad?

Due to Bluetooth’s limited bandwidth, it’s impossible to send audio without some lossy data compression techniques. Some audiophiles believe that lossy compression degrades audio quality inherently, and Bluetooth audio is therefore unacceptable to these listeners.

Using Bluetooth can be a bit of a headache.

Audio describes Bluetooth audio’s dirty secret as follows: Almost all high-end Bluetooth headsets today support AptX, an audio codec compression scheme that offers better sound quality than other compression schemes. 

You can connect your stereo system or soundbar to your smartphone and its many streaming services using Bluetooth. Despite its widespread use, Bluetooth remains the most misunderstood audio technology. 

Numerous Bluetooth codecs are available from audio companies. Some people claim that a particular codec will improve Bluetooth sound quality.

These differences, however, are difficult to quantify and even more difficult to hear.

The following information will help you determine whether or not different Bluetooth codecs should be considered when selecting headphones or speakers.

The sound quality on Bluetooth headphones and speakers is so bad, why is that? 

Reason #1

Undoubtedly, many Bluetooth headphones and speakers are priced at the low end. If you try to squeeze in a Bluetooth receiver, a DAC (digital to analog conversion), an audio amplifier, and the audio transducer itself for under £50, especially in stereo, you’re not going to get high-quality audio. 

When it comes to audio devices, Bluetooth has to compete with its wired counterparts. However, because wired devices often contain nothing but audio transducers, the quality is invariably much better than with Bluetooth for a similar price.

Although Bluetooth audio reproduction can be expensive, there are a few technical factors that limit the quality of the sound. 

Bluetooth headphones and speakers, on the other hand, tend to be battery-operated.

Large current transients are difficult for batteries to produce, and this can have a significant impact on musical dynamics and low-end response.

Not because you want to play the music louder with them, but because they can deal with audio transients more effectively, reproducing them accurately instead of distorting them.

Audio transmission over Bluetooth uses lossy audio compression to reduce the amount of available bandwidth. It’s true that most people would never be able to tell the difference between a good lossy compression at a reasonable bit rate and the original audio file. 

The problem with using lossy compression to deliver sound is that it’s very likely that the music you’re listening to has also been compressed.

Unfortunately, the second round of lossy audio compression introduces what is known as Digital Generation Loss (DGL), an audio quality issue. Compression artifacts become much more obvious after multiple rounds of lossy compression.

Reason #2

Why does the sound leak out of the portable speaker when it’s turned on? There are several reasons for this.

An ineffective ass amp is another. A lot of Bluetooth devices, especially those that use the aptX codec (hint: stereos, soundbars, and cars all use aptX) can sound really good when connected.

Improve the quality of your speakers and amplifier, or invest in high-quality headphones or a Bluetooth adapter for your stereo system. 

  • As a digital transfer scheme, Bluetooth is slower than WiFi at transferring data.
  • In addition, it uses the same 2.4GHz band as other WiFi devices. Wireless technology operates at 2.45GHZ, according to reports (which is still close enough to be disrupted by other devices) 

How is Bluetooth audio? 

A large number of consumer wireless audio devices include Bluetooth audio capabilities. Due to Bluetooth’s limited bandwidth, it’s impossible to send audio without some lossy data compression techniques.

Because some audiophiles believe that lossy compression inevitably degrades audio quality, they reject Bluetooth audio.

But just how bad is it? In this post, we’ll try to answer that question.

Low Complexity Sub-band Coding was the de facto standard codec for Bluetooth audio for many years (SBC). Since then, another codec has become more and more popular. AptX is the name of the program. 

CSR’s marketing materials are confusing. Although they have claimed that aptX delivers lossless CD audio quality sound, we’ve seen them claim otherwise. We don’t know exactly how the audio signal is compressed using aptX because it’s a proprietary format. 

Due to our lack of familiarity with aptX, we were skeptical of the claims made. In order to gain an objective understanding of this codec, we devised a few simple experiments.

Description of the experiment

It was decided to compare aptX with SBC and the 320Kbps MP3 codec. Unencrypted CD-quality test signals were used: 64-bit depth at 44100Hz sampling frequency. The following were the test signals:

  • A 1kHz tone that never stops.
  • A 10kHz tone that never stops.
  • White noise on a wide band of frequencies
  • A periodic jolt of electricity
  • Three musical compositions

Each of these test signals was compressed and decompressed using the target codecs, resulting in a 16bit 44100Hz wave file. If you’d like to compress your audio using aptX or SBC codecs, you’ll need a Macbook Pro with Bluetooth and a Bose Bluetooth receiver. 

Since digital-to-analog and analog-to-digital conversions introduce noise, the Bose receiver’s SPDIF output is directly connected to the sound card’s SPDIF input. So the signal is always in the digital realm. To compress MP3 files to 320kbps, we used Audacity’s MP3 compression tool. 

Thereafter, the recorded signals’ temporal- and spectral behaviors were compared to the original uncompressed signals. Data were processed in Matlab after they had been captured and analyzed.

This is just a heads-up that many of the figures will be represented as spectrograms. Inspecting the frequency content of a signal over time is possible with the spectrum analyzer. A typical spectrogram shows time and frequency on the x and y axes. 

Depending on the time and frequency of the signal, different colors are used to denote its magnitude, with red being the biggest and dark blue being the smallest. 

Does Bluetooth degrade the sound quality of your music?

There has always been a digital compression issue with Bluetooth audio: in order to send your audio to the headphones, you had to sacrifice quality. Since older devices and older Bluetooth versions suffered from this, the result was a robotic, buzzy, noisy, and all-around awful sound. 

When it came to music, they weren’t much better than listening to podcasts and spoken word. No richness or warmth in the sound that a wired pair of headphones can provide. 

The output of sound is affected by every step in the audio chain. When using codecs and wireless standards, they must work with hardware that may or may not be designed to produce high-quality output. When it comes to audio, Bluetooth has little impact on the sound quality of a device.

The quality of audio via Bluetooth is also a concern. We like the idea of wireless audio. Lossy data compression is required to transmit audio over Bluetooth due to its limited bandwidth.

Some audiophiles believe that lossy compression degrades audio quality inherently, and Bluetooth audio is therefore unacceptable to these listeners. 

Compression isn’t the only factor that affects audio quality. Wireless mice and keyboards, Wi-Fi signals, and even microwaves all use the same 2.4GHz frequency as Bluetooth. 

It’s unlikely that any of these factors will have a significant impact on sound quality, but they can cause audio drops and other issues. That’s why Bluetooth audio has never been a match for traditional wired audio, and it never will be. However, that doesn’t mean it’s devoid of value. 

How to improve the quality of Bluetooth audio?

Make use of the music stored on your device.

  • When you run multiple Bluetooth-enabled apps simultaneously on your device, the reliability can be affected.
  • Reboot the speaker or the device you’re using to pair with it if it’s not responding.
  • Disable Wi-Fi on your device and see if that helps.
  • It’s possible that the first app has a problem, so try using another one to get better sound.

Is Bluetooth a better option than an aux input for music?

Aux cords tend to wear out over time because they are a physical connection. Therefore, an Aux connection will always provide better audio quality than Bluetooth, and a digital connection (such as USB) will provide even better sound quality than Aux connections.

When Choosing a Bluetooth Audio Device Be Careful What You Look For 

Bluetooth’s audio compression has significantly improved over the past five years. Compared to Bluetooth 1.1 and 2.0, Bluetooth 3.0 and 4.0 devices are designed with stereo audio in mind.

Consider headphones and speakers that support aptX, an audio codec designed to transfer CD-quality audio over Bluetooth. 

Try to find a Bluetooth device that supports A2DP or Advanced Audio Distribution Profile. In either case, you may be able to find adapters to help bridge the gap, even if you don’t have supported devices.

Despite this, it’s still not as good as wired audio, and some people say it’s still unacceptably bad in general. But there are times when it’s good enough: 

  • Whenever you have a low level of expectation because we aren’t all audiophiles or audiophiles at heart, we don’t need the highest audio quality all the time. Maybe the luxury of not having to deal with wires is just too nice to argue against. 

When it comes to Bluetooth audio, as long as you’re aware of its limitations and accept that you’re not going to get high-quality sound, you’ll probably be just fine. If you listen expecting the worst and are pleasantly surprised, that’s an added bonus.

  • When portability is the most important factor to consider No matter if you’re talking about headphones or speakers, this is probably the most common use case for Bluetooth audio. 

Bluetooth headphones are a good option if you need to listen to your music far from the audio source, or if you’re exercising and don’t want to be tied down by a cable. For convenience, you’ll have to pay more for Bluetooth audio, because it’s more expensive.

  • In noisy environments where the quality of the audio isn’t really noticeable. When working in a noisy environment, a pair of Bluetooth headphones may be ideal for you. 

You won’t have to take them off your head to walk around. It’s the same thing if you’d rather be alone at your desk listening to your own music than chatting with coworkers, or if you work in an open-plan office where everyone can listen to every phone call or word typed by everybody else flexibility is essential. 

Even in our guide to noise-canceling headphones, we mentioned a few Bluetooth models that would be ideal for those office circumstances. 

  • Especially if you’re listening to mediocre-quality streams or lossy audio. However, if you’re looking for portability, and you already know you’re not listening to high-quality audio files or streams, it may all be for nothing. Even if you can’t differentiate and you want the comfort that Bluetooth provides, there is no reason for avoiding it. 

Even now, even if you don’t give a damn about fidelity, this reaffirms the significance of obtaining the maximum streams and rips you can, therefore the effects of audio compaction are as low as possible in the long run.

Feel free to explore the world of Bluetooth audio devices if any of them resonates with you.

It’s possible to be disappointed with a wireless listening experience if you’re the type who really enjoys listening to music on high-quality headphones, and you use terms like “soundstage” and “frequency response” to judge a pair of headphones against another.

Lastly, keep in mind how much you’ll end up spending just to get rid of those pesky cables. 

Conclusion

Bluetooth headphones are no different than any other kind of headphones when it comes to shopping.

Consider trying them out first (or buying from someone who has a generous return policy, so you can get your money back if you’re not happy with it).

It’s important to listen to music that you’ve grown to love. 

In addition to warranty information, check the battery life and recharge time reported by the company.

Read as many reviews as you can before making a purchase.

For as long as you understand the benefits and drawbacks of switching to Bluetooth and choosing the right headsets, you can make the decision to go wireless or adhere to wired earphones with trust.