In an interview the Apple developer responsible for AirPods, Gary Geaves, has revealed some interesting background information about the problems with, and the status of, Bluetooth.
The new AirPods 3 have now replaced the AirPods 2, but in our opinion they are still in the shadow of the very successful AirPods Pro, which are often discounted if you want to get a bargain (see: Best AirPods deals).
A few weeks ago What HiFi published an interesting interview with Gary Geaves, Apple’s VP of Acoustics, which answered some questions and could give some insight into the future of the AirPods Pro. (You may also like to read our round up of rumours about the AirPods Pro 2).
Of particular interest in the interview is the discussion of the limitations of Bluetooth – which has a bad reputation among HiFi fans as the data rate is limited for uncompressed audio data. This even applies to the AirPods Max.
Another problem with Bluetooth is the reaction speed – the amount of latency. For example, a fast reaction to head movements is required by Apple’s Spatial Audio (3D sound), which Apple achieves through a few tricks and special hardware.
Also Apple’s new hi-res resolution music – Hi-Res Lossless – is not supported via Bluetooth.
Discussing Apple’s new technologies Gevase says: “There’s a catch, as far as I can see it – a bottle-neck that’s been preventing real qualitative leaps in the sound of wireless headphones essentially since wireless headphones came into being. I’m talking about Bluetooth, of course, which almost all wireless headphones, including AirPods, rely upon and which doesn’t have the data rate for hi-res or even lossless audio
Greaves suggests there could soon be innovations here saying: “It’s fair to say that we would like more bandwidth and… I’ll stop right there. We would like more bandwidth”.
How can Apple get this extra bandwidth? Well, Apple still relies on Bluetooth 5.0 for the AirPods 3. Apple is probably planning to introduce 6GHz Bluetooth.
As explained by c;t Magazin (in German), Bluetooth’s current restrictions are caused by its use of the 2.4GHz band. This means only low data rates are possible – about a maximum of 2Mbit as a transfer rate. Hi-Res requires up to 10MB/s so high-resolution audio material, and better sound, are thus excluded.
At least in the EU the sale of 6GHz Bluetooth devices would be permitted, so it’s certainly possible that Apple will make this move. It would only have to prove conformity with the CE standard and Apple would be free to introduce 6GHz Bluetooth.
But there is another possibility: Maybe only an update to Bluetooth 5.2 is required? This new standard brings many improvements, such as a new audio codec called LC3. In addition, Qualcomm has an audio standard with aptX that enables high audio quality via Bluetooth. However, we can’t see Apple using this alternative.
We suspect that there will be some updates on Bluetooth at the WWDC developer conference in June.
With the second generation of AirPods Pro due, it looks likely that Apple is prepping some innovations, such as better audio bandwidths. Theoretically this could then reach the AirPods 3 via an update.
Also interesting in the WhatHiFi interview is Geaves’ explanation of why Apple has chosen an open design for the AirPods 3, rather than the completely closed design of the AirPods Pro (thanks to the included silicone tips). The AirPods 3 sit as loose as the AirPods 2 did.
The open design means that noise cancelling isn’t possible. However, the choice was intentional because many AirPods 2 users wanted a loose seat. Some prefer to be able to hear more of what’s going on around them and others find this design more comfortable.
This causes problems for sound design because no ear is shaped like another. However, this is compensated for by an inward-facing microphone that automatically adjusts the bass and mids. This Adaptive EQ feature was first introduced to the AirPods Pro and is one of the innovations of the AirPods 3.
One point of contention with headphones is always going to be whether the user hears the music as desired by the musician. According to Geaves, Apple puts a lot of effort into this: in addition to a very analytical approach, a team of experts from critical (human) listeners and tuners is also used – many whom come from the professional audio industry. As a result AirPods should sound very accurate.
In fact, several departments work on the subject of spatial sound, in addition to the Acoustics team, such as the departments for Apple Music, GarageBand and Logic.
Above all the different head shape is a problem – described as HRTF (head related transfer function). Thousands of measurements have been carried out to find a solution suitable for as many people as possible. When used for music, Apple primarily aims at a natural sound, less at effects. For example, Apple uses different settings depending on the output device: on an Apple TV the virtual speakers are set further away than on an iPhone.
The AirPods 3 are still somewhat in the shadow of the AirPods Pro, which means that many of the new innovations seem inconspicuous in comparison. However, this should not be a surprise as the AirPods Pro have a higher price and the Pro name. The new Bluetooth standards may well be destined for the new AirPods Pro, along with raised prices for the Pro models.
This article originally appeared on Macwelt. Translation by Karen Haslam.