The Bluedio T4 have a better design and sound quality than the previous models but a drastically worse latency performance. They're sturdy and durable headphones with an awkward fit that may be better for some listeners if worn backwards. However, the biggest issue is with the incredibly high latency that makes the headphones practically unusable for watching videos except when wired.
The T4 have a much better design than the T2S and the T3 Plus. They still look a little odd due to their protruding hinges but they feel a lot more premium than the previous models. They have a brushed metal finish for the ear cups and a wide well-padded headband that's reinforced with a metal frame. However, they're wont to be the most stable headphones to run with. They're also a bit difficult to carry around on your person without a bag and although good their control scheme can be a bit confusing.
The Bluedio T4 have a premium look and feel but an odd form factor that might not be for everyone. They feel high-end thanks to the ample use of metal in their design and the thick well-padded headband. That and the brushed metal ear cup enclosures will stand out in a crowd, especially, if you get the white or red color variants. However, the ear cup hinges protrude outwards, which won't look as good to all listeners.
The T4s are well-padded but have an uncomfortably awkward design. The ear cups rotate in only one direction and have a small opening that doesn't fit well on all ears. For some listeners, the T4s are actually more comfortable when worn backwards, due to the limited range of motion of the swivel hinges. This leaves a big gap behind the ears that feels a bit annoying and results in seal issues, which affects the noise cancellation and sound quality of the headphones.
These headphones have a better control scheme than past iterations but feel a bit confusing. They deliver all the essential functions; call/music, track skipping, and volume controls. They even have dedicated buttons for noise canceling and a talk-through mode. The buttons provide good tactile feedback but the volume toggle, the multi-purpose and the talk-through buttons feel like they should have been switched around to be more efficient and easier to use. Also the ANC switch feels quite stiff in actual use.
The Bluedio T4 are solid and durable headphones. They have a good build quality that's mostly metal and thick faux-leather padding for the ear cups that feel somewhat high-end. The ear cups are dense and the headband is reinforced with a decently flexible metal frame. The hinges are their most susceptible weak point but overall they feel like sturdy headphones that could fall a couple of times without getting damaged. Their build quality is even better than some headphones a lot more expensive like the Turtle Beach Elite 800.
The T4 are not particularly stable but have a wireless design that reduces the possibility of the audio cable getting tangled and yanking the headphones of your head. They won't fall during casual listening sessions but they're not stable enough for running or working out. They won't be the ideal headphones for sports.
The Bluedio T4 is an average-sounding pair of closed-back headphones and a big improvement over the previous T2S and T3 Plus models. The T4 has a deep and extended Bass, an average Mid and a decent Treble reproduction. They also perform consistently across multiple people, despite their poor ergonomics. They also have low harmonic distortion. However, their Bass could a bit too thumpy, their Mid Range is slightly recessed, and their Treble sounds a bit too forward on certain tracks. They also lack an open Soundstage, which is typical of closed-back headphones.
Good Bass Range performance. Low-bass is extended down to 10Hz which is great, but it's over our target by about 4dB. This will add a bit of excess thump and rumble to the sound, which some people may like. Bass is relatively flat, but slightly underemphasized. High-bass is also flat, but under our target by 4dB which makes the overall sound to lack a bit of warmth.
Average Mid Range performance. Low-mid is relatively flat, but underemphasized by about 3dB. This is the continuation of the high-bass underemphasis, making vocals/leads slightly thin. The bump from 800Hz-2KHz pushes lead instruments to the front of the mix and could also make the overall sound a bit honky.
Decent Treble Range performance. Low-treble is over our target by 4dB, which is the continuation of the high-mid overemphasis. This adds a bit of excess presence to the mix. Treble is pretty consistent and balanced, but high-treble shows a bit of underemphasis which means these headphones could lack a bit of airiness.
Excellent frequency response consistency. Despite the poor ergonomics, these headphones performed relatively consistently across our human subject. Even having glasses on didn't have a dramatic effect on Bass compared to some other closed-back headphones we have measured so far. The T4 also performed quite consistently in the Treble Range, most likely due to their small ear cups.
Good Harmonic Distortion performance. The overall level of the distortion is within good limits and doesn't change much under heavier loads, which is good. However, Low-bass, shows a bit of increase in distortion at 100dB SPL, but it's still within the normal performance.
The T4s have a decent noise isolation performance that's ruined by their awkward fit. They do not create a good seal around the ears so if you don't have any music playing, the ambient noise will be distracting. If you can better the fit then they should be decent enough for commuting in moderately loud environments but they won't be ideal, although they do much better than the Plantronics BackBeat Go 600. On the upside, they do not leak too much even at higher volumes, which makes them a decent option to use in quieter settings.
Mediocre Isolation performance. These active noise-cancelling headphones add some ANC artifacts below 40Hz which may be audible in certain situations. The T4s ANC kick-in at around 40Hz and achieve about 3dB of isolation in the Bass Range which is sub-par. In the Mid Range, they achieve a decent reduction of about 13dB and in the Treble Range, they isolate by more than 30dB, which is good.
Above-average Leakage performance. The significant portion of the leakage is spread between 600Hz and 3KHz, which is not too broad. The overall level of leakage is also with decent limit. However, the leakage performance of these headphones headphones may be negatively affected by their poor fit, since not everyone will be able to achieve a proper seal with them.
The Bluedio T4 have a decent wireless range and an above-average battery life. Unfortunately, they have the highest latency that we've measured so far so unless you're only listening to music with these headphones the latency will be a deal breaker. They're incredibly out-of-sync when watching videos and will be the worst wireless headset for gaming. You could always use them wired but that defeats the purpose of having a wireless headphones.
These headphones have a decent battery life that should last all day even with heavy usage. They also charge relatively fast for their battery life, but unfortunately, they don't have many power saving features. They have a good standby time but do not automatically switch off to save power.
No compatible app.
The range of the T4 is about average when the Bluetooth source was obstructed and slightly below-average in direct line-of-sight. They reached just above 30 ft indoors with a lot of walls so they should be somewhat decent headphones to use around your house. However, their pairing procedure is a little tedious. They don't support NFC and sometimes require the ANC to be switched off before you can enable pairing. That and the confusing placement of the Bluetooth button can get a bit frustrating.
The Bluedio T4 have the worst wireless latency that we have measured so far. They are unusable for watching movies or gaming and are only somewhat practical if you're just listening to music. We tested these headphones with 3 different Bluetooth dongles and a couple Bluetooth-enabled mobile devices and the results were the same. The latency will be a deal breaker for most listeners except if you used them wired or don't care about latency at all.