AIAIAI TMA-2 Studio Wireless

AIAIAI’s latest wireless cans make cable‑free headphone monitoring a reality.

Most of us would agree that cables are a necessary evil. Indeed, much of the tech world has spent considerable time and energy eliminating them. I’m typing this on a wireless keyboard, for example, next to which is a wireless mouse, a wireless phone charger, a wireless Xbox controller and a wireless gaming headset. The live‑sound industry has also gone wireless in a number of areas, with WiFi control of mixers now common, and audio often being beamed around venues wirelessly in the case of microphones, guitar signals and in‑ear monitors. So why is the studio world still so wedded to copper cables?

The answer boils down to two factors: latency and quality. Latency is especially important when recording; any noticeable delay in a foldback mix can be extremely distracting during a take, and Bluetooth, the most common consumer wireless standard, can incur up to 250ms. Even modern ‘low latency’ codecs have a latency of around 40ms, which is more than enough to put you off your take. There are analogue wireless systems that don’t incur latency at all — UHF radio systems, for example — but they often require licences to operate, and so tend to be used only by large‑scale live shows and touring companies.

When mixing, latency isn’t such an issue, but quality certainly is — and although some wireless digital systems are able to achieve fairly low latencies, they tend to do so by either restricting bandwidth or using lossy compression, neither of which processes you want to be mixing through.

Great Danes

One company that have tried to square this circle are Denmark’s AIAIAI, whose Unit‑4 compact monitors we reviewed in SOS July 2024. As well as being very good monitors in their own right, the Unit‑4s shipped with a dongle, called the X02, that could transmit audio wirelessly to the Unit‑4 speakers — at 44.1kHz/16‑bit quality, and with latency down to 16ms — using their own proprietary W+ Link protocol. The X02 dongle can accept audio either via a mini‑jack, or over USB, in which case it also acts as an audio interface.

Impressive as the Unit‑4 system was, there is perhaps limited demand for wireless studio monitors. Unless you plan on making new friends on the train, sitting in front of studio monitors is usually done at the studio, with other gear plugged into the mains, where there’s limited advantage to speakers being portable.

An arguably more useful application for high‑quality, low‑latency wireless audio in the studio would be headphones, and clearly AIAIAI agree, because they’ve since released a number of wireless headphones aimed at DJs and producers. I was sent their new TMA‑2 Studio Wireless to review, although there’s a related model that pre‑dates it by a couple of years, the Studio Wireless+ (normally the ‘plus’ version of something is the later model, but not this time!). A third model, aimed at DJs, is called the TMA‑2 DJ Wireless, and offers increased output and a “loud sound”, by which I guess they mean a more hyped frequency response.

There are also a number of wired headphones among AIAIAI’s products, and the entire range (wired and wireless) is completely modular. So you can upgrade a pair of (non‑wireless) TMA‑2s to the Wireless version by buying the necessary driver/receiver modules and a transmitter (they come as a set). Or, you can swap out the E04 on‑ear earpads on the Wireless for the over‑ear E08 pads that come with the Wireless+. Each model comes with its own unique combination of driver units, transmitters (for wireless models), earpads, headband and cable (straight or curly, black or neon green), and you can even order your own custom headphones by cherry‑picking the components you prefer. As well as offering the customer greater choice, this also means that AIAIAI headphones can easily be repaired and recycled. The company use recycled plastic wherever possible, and their packaging is also commendably eco‑conscious.

TMA‑2 Studio Wireless

The X03 transmitter uses AIAIAI’s proprietary W+ Link protocol to send audio wirelessly with latency down to 9.5ms.The new TMA‑2 Studio Wireless differs from the older Wireless+ in a few ways (it features a slightly different headband and earpads), but the most significant difference in terms of wireless performance is the transmitter. The X03 is the newest iteration of AIAIAI’s W+ Link technology, and although it transmits at a slightly reduced quality (compressed, at the equivalent bit rate of a 320kbps MP3), its latency is significantly lower, at 9.5ms. It also trumps the X02 in that it has its own built‑in battery, and so doesn’t need a separate power supply when being used through its analogue mini‑jack input. Like the X02, though, the X03 can work as a two‑out audio interface. No Windows drivers exist for it, sadly, which means that in order to use it as a DAW interface on Windows, you need to install the generic ASIO4All driver. That said, with a 32‑sample buffer size I was able to achieve a latency of under 2.5ms. A more CPU‑friendly 128‑sample buffer size resulted in 3.9ms, which, added to the X03’s 9.5ms, gives a still very decent latency of 13ms — which many people will find low enough to track guitars and synths, if perhaps a little sluggish for monitoring vocals through your DAW. For mobile use, and where latency isn’t an issue, the TMA‑2 Studio Wireless headphones can also play audio over Bluetooth.

The unboxing experience was a surprise, because despite the box being of ample size to hold a pair of headphones, what you actually get is a sort of headphone kit: five sealed bags (made out of recycled plastic) containing the S11 drivers and X03 transmitter, the H03 headband, a pair of E04 ear pads, a C05 straight mini‑jack cable, and an A01 protective pouch. You also get a card offering a free Ableton Live Lite licence when you register the headphones, and a Get Started leaflet which explains how to put the headphones together. Assembly was the work of just a couple of minutes.

AIAIAI’s headphones are modular, so you can swap out and replace parts, or custom‑build headphones to your own requirements.

The left and right sides of the headphones are marked with an indented L and R on the insides of the headband. The right‑hand driver unit houses a USB‑C port for charging (AIAIAI claim 20 hours of battery life for the headphones when connected via W+ Link, or 40 when using Bluetooth), and a four‑way joystick. This joystick offers volume control (up and down on the stick) for the integral headphone amp, plus generic media transport controls (next/previous track, play/pause and so on) when using Bluetooth. The left‑side driver unit houses a mini‑jack input for traditional analogue wired use, which of course bypasses the headphone amp and DSP (see box). The drivers themselves are moving‑coil designs, powered by a neodymium magnet and featuring AIAIAI’s ‘signature’ 40mm bio‑cellulose diaphragms.

The X03 transmitter, meanwhile, is a smooth plastic box around the size of a Zippo, though much more lightweight, at 60g. Being a little insubstantial actually works in its favour: since it’s so light, I didn’t feel nervous simply dangling the X03 off the back of a synth or interface using the supplied mini‑jack patch lead. Said lead is also right‑angled at one end, further reducing cable strain.

Battery life for the transmitter is given as 40 hours, and I never ran out of juice on either the X03 or the headphones, provided I popped them on charge at the end of a full day’s listening. Charging time for both is specified at two hours, but since I never ran the battery down I never needed to charge that long!

Down To The Wire

Plug the supplied mini‑jack cable into the left driver unit and you don’t need to worry about battery life or latency; the TMA‑2 Studio Wireless become a simple pair of passive moving‑coil headphones. Specs‑wise, they’re pretty typical of moving‑coil headphones, with an impedance of 32Ω, a sensitivity of 97dB/mW, and a frequency response that’s fairly typical of closed‑back headphones, in that there’s a low‑end boost below around 200Hz, and a rather narrower peak at the other end, centred around 8kHz.

At 227g, the TMA‑2 Studio Wireless are light, but without feeling cheap, and the earcups can be clicked up and down to one of nine positions on the headband on either side, so there’s a wide range of fit. They don’t pinch too hard, and with pleather‑covered memory foam in both the earpads and the underside of the headband, they are comfortable to wear for long periods. The earpads are relatively small for over‑ear types, and not particularly deep, so while they do fit over the whole ear, they feel almost like on‑ear headphones, and place the drivers quite close to your ears.

Sound‑wise, they feel a little less extended at the extremes than my usual closed‑back AKG K872s, although those are considerably more expensive. Lows and lower mids seem perhaps a little bloated in comparison, but not to the extent that I couldn’t acclimatise to it. At the other end of the spectrum, highs were presented very cleanly indeed, with cymbals, tambourines and guitar string squeaks presented clearly but without being overbearing.

Isolation was very impressive, perhaps even better than my AKGs (which themselves are excellent at shutting out the outside world), so I’d be more than happy to use these for foldback in close proximity to microphones. I was also able to drive them far louder than I’d consider safe using my MOTU interface, so I’d say they’re very much drummer‑friendly headphones too.

One minor quibble is that cable‑borne noise was very noticeable; any mechanical sound from the cable being bumped or brushed against things was transferred very efficiently to the left earcup. Happily, though, that’s not an issue when you go wireless...

The connection was remarkably robust; I was able to listen to my DAW while standing on my driveway...

Linked In

Pairing the headphones to the X03 transmitter proved to be entirely automatic; the W+ Link connection seemed to have been pre‑configured out of the box and wasn’t something I had to do manually at all (though I did occasionally forget that I was in Bluetooth mode; a simple double‑click of the joystick switches between Bluetooth and W+ Link). The connection was remarkably robust; I was able to listen to my DAW while standing on my driveway (a surprisingly surreal experience!), and if I did test things by walking too far, the audio simply went a bit robotic and Aphex Twin‑y before cutting out. Importantly, the glitching was never louder than the wanted audio, so you won’t fry your ears if you feel the sudden need to run away from your DAW as fast as possible. When the connection dies completely, the headphones give you a friendly beep to let you know. Move back within range and you get another set of beeps and the connection starts again; there’s no need to re‑pair or anything.

In terms of the W+ Link’s quality, I could just about convince myself I could hear a difference in the very high frequencies caused by the lossy compression, but I could just as easily talk myself out of hearing anything... Which tends to be my experience when comparing high‑bit‑rate compression to PCM audio! Which is to say that the quality is very good, and certainly good enough for composing and making rough mixes, if perhaps not for mastering (for which you can always just plug the mini‑jack in, of course).

One potential issue I encountered early on was that of noise. Out of the box, the TMA‑2 Studio Wireless had its built‑in headphone amp turned up almost to max, which roughly matched the level I was getting when using them wired, but with some very noticeable added noise. Turning the volume down on the headphones solves this to the point where the noise is inaudible, but requires you to turn the signal going into the X03 transmitter up (by around 12dB, I estimate). My MOTU interface’s headphone amp was more than up to it, but this is worth bearing in mind if you routinely use your own headphone amp near its maximum level.

Conclusion

In upgrading their W+ Link system from the X02 to the X03, it seems AIAIAI decided that ‘almost lossless’ rather than ‘fully lossless’ was worth it for the sake of a significantly reduced latency, and I’m inclined to agree. If you’re doing mission‑critical mixing and mastering, you’re likely to be very focused on what’s happening in your DAW, and so unlikely to be moving around a great deal. But where wireless headphone monitoring really comes into its own, I think, is at those times when you’re likely to be more animated: pacing up and down your studio while listening to an eight‑bar loop and wondering what should come next, for example. In fact, for those times when it’s beneficial to look away from your screen — while composing, tweaking an arrangement, or evaluating a collaborator’s handiwork, say — the TMA‑2 Studio Wireless could be a genuinely useful studio tool. If your studio setup is largely comprised of different synth racks, then again these headphones could be ideal, allowing you to wheel about on your studio chair from synth to synth without garotting yourself on a curly cable. I can also imagine modular synthesists, who have enough cables to contend with, benefitting from AIAIAI’s wireless technology.

One final consideration is that, with their ability to work as standard wired headphones, in low‑latency W+ Link mode, and also with consumer devices over Bluetooth, these could easily end up being the only headphones you’ll need, whether for studio work, gaming or just general listening.