SOUNDPEATS Air4 TWS Earbuds Review: A worthy upgrade to the Air3?

The SOUNDPEATS Air4 are part of the fourth generation of semi-open earbuds series and, alongside the Air4 Lite, they try to showcase the progress that the engineers at SOUNDPEATS have managed to accomplish over the past year.

And design wise, the SOUNDPEATS Air4 are clearly improved over the last generation, but are these changes only skin-deep? Not really because the developers have been bold enough to add ANC to a pair of semi-open earbuds and, as we already have come to understand, ANC without a good seal just asks for trouble.

SOUNDPEATS says that this is no ordinary active noise canceling and that it’s programmed ‘to listen’ to its environment and adjust the level of low-frequency sound suppression accordingly. We will see how well this works during our tests. Besides ANC, the SOUNDPEATS Air4 also prides itself with the support for aptX lossless codec which should offer a far better sound quality than SBC or AAC, and, it seems that this feature is also adaptive, managing to adjust the bitrate according to the played content.

Lastly, these earbuds have also added the latest Bluetooth version (at the moment of writing), the v5.3, which is a welcomed addition. That being said, I am curious about the sound quality of the SOUNDPEATS Air4 and how well ANC actually works with these types of earbuds, so let’s put them to the test.

Build Quality and Design

Ever since Apple assumed the semi-open ear TWS earbuds for its AirPods line, everyone has been calling everything that remotely resembles the traditional earbuds, a clone of Apple’s TWS earbuds. It’s obviously not fair, but at the same time, the charging case that comes with the SOUNDPEATS Air4 does betray some design inspiration from the AirPods.

The earbuds themselves are small and lightweight enough to forget you’re actually wearing them. There is an elongated neck which houses the Bluetooth antenna, while at the top, there’s the part that actually goes in the ear, containing the speaker and the microphones. There seems to be three of them – one larger on the side, one at the top and one near the bottom, very close to the two charging pins. The color palette that the manufacturer went with is matte black for the most part, with some glossy portions and some copper-like accents.

The most obvious portion being on the outer side and, as you may have expected, this is where SOUNDPEATS has added the multi function touch sensitive button. A single tap on the left/right earbud will decrease/increase the volume, while a double tap will pause/play a track. Additionally, if you receive a call, you can answer it with a double tap (or hang up) and, to return to a previous track or move to the next, you need to tap and hold for a second and a half on the left or right earbud. I also need to mention that there is a Game mode for a better latency which can be enabled by triple-tapping the left earbud (it’s not going to be better than a cabled connection).

I mentioned that it’s possible to forget that you’re wearing these earbuds which means that they’re very comfortable over longer periods of time, but are they suitable for outdoor activities? It’s up to you. I usually say that it’s better to go with some sport headphones (those with a wire around your neck or some sort of hooks on the earbuds to keep them in the ear), otherwise you risk losing them. And good luck finding them in a busy road or in the subway.

At the same time, the SOUNDPEATS Air4 are IPX4-rated which means that it has some basic protection from water, but nothing more. And it’s actually a step backwards from the Air3 which was IPX5-rated, a better water protection. You can’t swim while wearing them, you can’t shower with them and I think the reason may be the large microphones, but I may be wrong. In any case, sweat should not be a problem, but yeah, keep the SOUNDPEATS Air4 away from water.

SOUNDPEATS Air4 Charging Case

I did mention some similarities with the Apple charging cases and yes, the SOUNDPEATS Air4 does have a compact oval case covered by a black matte finish. But it does have some elements of style to enhance its overall look. The finish is soft to the touch, there’s a small copper-like plate with the logo on it and there is a middle band that cuts across the charging case.

The border around the USB-C port also seems to be made of copper, so, overall, it’s a nice-looking case. I did see that there is a button on the front which, once pressed, it will light up an LED to show the status of the battery life. Green means that the battery is between 50 and 100%, yellow that it’s more than 10 percent and red means that it’s below 10% and you do need to charge it. It’s obviously not a very accurate system and I suppose nothing beats the actual percentages shown by the charging case of the TOZO Golden X1 (which costs about double the price of the Air4 at the moment of writing).

I should mention that the earbuds are easy to remove with your fingertips from the case and that the lid is magnetic. Also, the case measures 2.3 x 2.1 x 0.9 inches (5.8 x 5.4 x 2.4cm), so it’s very compact and you can easily slip it into your pocket, just be careful not to lose it – I wouldn’t be against some lanyard ring.

Internal Hardware and Connectivity

The SOUNDPEATS Air4 earbuds use 13mm dynamic drivers, a step down from the 14.2mm drivers of the Air3, but then again, the Tozo Golden X1 are able to give a very good sound quality using 12mm drivers, so there are other important aspects besides the driver size, such as the tuning. As for the SoC, the SOUNDPEATS Air4 relies on the Qualcomm QCC3071, an entry-level chip, but quite power efficient. In terms of Bluetooth version, we’re dealing with the v5.3, so range-wise, expect the usual 30 feet with some interference and a high ceiling for bitrate.

And yes, we do get aptX Lossless (24-bit/96kHz) support which will require a higher bitrate, but it won’t put a strain on the maximum allowed by Bluetooth 5.3, far from it. There is also support for multi-point, which is now getting more common even in the sub $100 price range.

Bluetooth Multipoint

The SOUNDPEATS Air4 can be connected to a couple of devices at the same time and, while I do look forward to seeing even more simultaneous connections, it’s a still a very nice feature to have. The pairing process is less convoluted than with the Haylou PURFREE Lite, so it requires the connection with a first device, then to turn off the Bluetooth on said audio source. Then, pair the SOUNDPEATS Air4 to the secondary device, enable the Bluetooth on the first and that’s about it.

The earbuds should be connected to a couple of audio sources at the same time. Know that calls will take priority, so if you’re listening to a song on device B, but device A receives a call, it will automatically switch to the latter. Also, the switch between the device is fairly quick, taking about a second for the action to succeed.

The Sound Quality

Since the SOUNDPEATS Air4 uses aptX, the iPhone 12 was out of the question, so I paired the earbuds to an AGM Glory Pro Android smartphone. And, after confirming that the connection uses aptX, I relied on Amazon Music for higher quality format files.

But, before talking about actual songs, I had to check some slightly more technical aspects of the SOUNDPEATS Air4, the first being the driver quality test. While the volume was set at volume 70%, the sweeping sound moved between frequencies without producing any buzzing. Next, I checked the quality of the drivers and this can be a bit tricky when dealing with TWS earbuds since an uneven seal can have an impact on the sound quality. The good news is that the sound felt like it was straight in the middle of my head, with no deviation, despite dealing with semi-open earbuds.

Afterwards, I had to play a few binaural recordings for that initial idea about what the SOUNDPEATS Air4 are capable of. The volume remained at 70% and the tracks were very detailed, and there was some fair amount of depth to the sound. The imaging was well done and I could tell where each instrument was, as well as the location of the singers. As for the sound stage, it is not very wide, but I couldn’t call it narrow either. These observations have been made while ANC was on, a feature that’s enabled by default. What about the Normal mode? While I usually preferred the sound without ANC on most of the earbuds I have tested so far, I think this is the first time when ANC does make a difference for the better.

The sound simply gets flat, the bass suffering the most, getting devoid of any substance, so I just turned ANC on again for the list of the usual songs. The first is the low-bass focused song called Faded by Zhu and it’s better than expected. The low bass, at least for this particular song goes fairly deep and despite not having the ears fully sealed, it has more substance than expected. I won’t deny though that the male voice felt a tiny bit forward, but we will get a better picture with other songs. For now, let’s move to the mid-bass song Morph the cat by Donald Fagen.

The song is definitely more colorful than I was used to and there is a very nice depth to the song; the voices and the instruments felt very close together, but without an impact on the clarity, so not bad, SOUNDPEATS, not bad at all. But now it’s time to see if these earbuds can handle lots of instruments and voices crammed together in the song called Mr. Jack my System of a Down (a track that likes to get muddy). The voices were very nicely differentiated from the instruments and, for the most part, everything is nice and clear, but when everything is played at the same time, the sound does get a bit muddy at times.

Before I get to the mids and treble, you may ask why I didn’t turn off ANC, is the bass representation that bad? It’s really night and day – I don’t really know why SOUNDPEATS even bothered adding the Normal mode, even though I assume it’s for battery reasons. In any case, I played the next track which was She Burns by Vance. And it’s a very detailed reproduction, as I could hear each instrument with excellent clarity, but if you remembered, I was curious whether the male voice was forward. It doesn’t seem like that’s the case at all, so now I wondered about the position of the female voice.

That’s why I played Breathin by Ariana Grande and it does seem that the female voice is a bit forward, slightly dominating the song, overshadowing the somewhat anemic bass. Lastly, I wanted to hear a treble-focused song, so I chose Sweet Child o Mine by Guns n Roses once again. The song is clear and detailed, AXL’s voice is perhaps a bit forward, but overall, the treble is fairly well reproduced, so it will not cause fatigue listening to multiple such tracks in a row.

Since the SOUNDPEATS Air4 are semi-open earbuds, there has to be some sound bleed, right? Well, yes, despite the sound being fairly directional, if you’re listening at a higher volume (70%+), anyone near you will be able to hear what song you’re listening to.

How good is the ANC?

ANC is really good for improving the sound quality of the SOUNDPEATS Air4, but can semi-open ear design actually subdue external noise? It could not cut the sound of me typing on the keyboard at all, but it did manage to limit the dB of a UPS that’s always ramping up its fans for no reason. So, it’s there, but in a fairly limited fashion. Would it do just as good on a plane, with those loud engine noises?

I don’t think so, but for some subtle fan noise and even some car passing outdoors, it can definitely limit their impact almost completely. I think that the ANC was actually added for enhancing the sound and not really for proper environmental sound cancellation.

The App

The SOUNDPEATS Air4 do have an app and it’s the same one that I used when I tested the SOUNDPEATS RunFree air conduction headphones. The app will automatically detect the earbuds and, after a few seconds, it will also show the amount of battery that’s left and, towards the bottom of the page, there are a few important sections. We are the most interested in the first one called Customized.

Here, you can enable the Adaptive EQ which will use the microphones to get an idea about how much the external noise needs to be suppressed in order to get a decent call quality. Then, you can choose between the fairly varied amount of Presets or you can just adjust the EQ yourself – this is most likely the most important feature and the raison d’etre of this app to begin with. After a firmware update, I can see that the developers have also added a way to choose between the two Noise reduction options, to enable the Game Mode or to ‘Disable all functions of the multifunctional buttons’. I do admit they’re a bit too reactive, but I am not sure I would prefer to use the app for every action – the options is there if this is what you like.

The Call Quality

After calibrating the earbuds to my fairly quiet office, the three mics per earbud did a good job at keeping environmental noise down. I wouldn’t say that my voice sounded perfectly natural, as it did with a far more expensive pair of headphones, the Sony WH-1000XM3, but it was acceptable considering the price tag of the device. Now, what about in a busy coffee shop? It’s also not bad at all, better than a lot of other earbuds – my voice would always be pushed towards the front. As for loud streets, they’re OK, but you may have to talk a bit louder to be properly heard.

The Battery Life

Each of the two SOUNDPEATS Air4 earbuds are equipped with a 35mAh battery and the manufacturer claims that they could reach up to 26 hours when taking the charging case into account. No idea about the single charge. Anyway, I tested them myself using aptX, continuous songs from Amazon Music (far from advertising since it’s a terrible service, but great quality songs) and the volume was pretty much always at 60%. I left ANC on since I didn’t like how the music sounded when this feature was off and, on a single charge, I got very close to 4 hours which is an OK result, I suppose.

The Conclusion

Besides the far improved build quality, it seems that the SOUNDPEATS Air4 are not significantly better than the Air3, but there is some progress in the sound quality nevertheless. The bass sounds better and deeper, and the ANC system does help a lot with the audio performance across the entire spectrum of frequencies.

The Normal mode is not really usable, so I think SOUNDPEATS should just scrap it and perhaps add a slightly larger battery. I am not saying that 4 hours is not enough, but on a long commute, you do have to recharge it at least one time, so bigger is better in this case. That being said, I think that the SOUNDPEATS Air4 are among the better options in their price range, so give them a chance if they fit your needs.