John Darko
iFi’s Neo iDSD 2 is a DAC and headphone amplifier that boasts the following: a dual-mono balanced analogue circuit (that iFi calls PureWave); balanced and single-ended socketry for head-fi and hi-fi rigs; 5 Watts of output power into 32 Ohm headphones (and 650mW into 600 Ohm loads); a 2″ ‘Retina-grade’ TFT display; a 32-bit 16-core XMOS Cortex microcontroller that reportedly ‘unlocks’ the sound of the Burr-Brown DAC chip; separate pathways for PCM (up to 32-bit/768kHz) and DSD audio data streams (up to DSD 512); Femto-clocking of those streams; a BNC socket for external clocks; and a suite of wired digital inputs – USB, coaxial and TOSLINK – to get those audio streams into the Neo iDSD 2.
But wait, there’s more.
iFi is reserving its promotional megaphone for the Neo iDSD 2’s Bluetooth input, which supports Qualcomm’s aptX Lossless codec. As we’ve covered numerous times within these pages, all other audio codecs found in the Bluetooth spec are lossy. LDAC is lossy. aptX HD is lossy. AAC is lossy. SBC is lossy. The Neo iDSD 2 is the world’s first DAC to support lossless Bluetooth audio reception.
From iFi’s press release:
“The headline addition for this next-generation iFi module is aptX Lossless – the first ‘lossless’ Bluetooth audio format. While other Bluetooth formats described as ‘hi-res’ already exist – for example, aptX Adaptive can stream audio up to 24-bit/96kHz and LDAC’s specification stretches up to 32-bit/96kHz – these are ‘lossy’ formats. That means they compress the file by removing audio data that is considered less important to the end result. These ‘hi-res’ Bluetooth formats apply compression that is more efficient and less audibly detrimental than older codecs, but sound quality is still compromised.”
“aptX Lossless is the first Bluetooth audio format capable of streaming CD-quality (16-bit/44.1kHz) audio ‘losslessly’ (although technically it still applies some compression). It achieves bitrates of up to 1.2Mbps at CD-quality – that’s more than twice the maximum bitrate of aptX Adaptive and aptX HD, and roughly 20 percent higher than LDAC’s maximum figure. The format’s potential to further elevate the sound quality that can be achieved over Bluetooth is very significant indeed.”
But there’s a catch: as with any other audio codec used for Bluetooth audio carriage, both the transmitting device (the source) and the receiving device (the sink) must feature support it. We therefore need a smartphone (or tablet) that does aptX Lossless for it to ‘carry’ the audio signal wirelessly and losslessly to the Neo iDSD 2.
Back to the press release: “aptX Lossless is part of Qualcomm’s Snapdragon Sound platform. To benefit from the format, both the source device (perhaps an Android smartphone) and the receiving device (Bluetooth headphones or earphones, a DAC or an audio system) must incorporate a suitably equipped Snapdragon chipset. The NEO iDSD 2 is the world’s first DAC – indeed, the first audio component of any kind – to include aptX Lossless decoding and iFi has worked closely with Qualcomm to ensure its benefits are maximised.”
Tackling the elephant in the room, no Apple product, current or foreseen, supports Snapdragon Sound. Heck, no iPhone or iPad supports any Bluetooth codec beyond AAC (and the mandatory SBC). Apple users might end up waiting a very long time before aptX Lossless transmission arrives in an iPhone, not least because Apple and Qualcomm have been involved in litigious spats since 2017.
That leaves Android users in the aptX lossless Bluetooth game. But not all of them. We can immediately strike off Samsung and Google as none of their current models supports Snapdragon Sound. That leaves Sharp, Sony, Vivo, Motorola, Asus and Nubia to carry the aptX Lossless torch. You can find a full list of compatible smartphone models here.
The upshot: if we want to stream audio losslessly via Bluetooth to iFi’s Neo iDSD 2, you’ll need a phone from that list. Take note: we are not just looking for devices that support Snapdragon Sound but those that specify Snapdragon Sound with aptX Lossless.
Enough about the iFi unit, what other sink devices support aptX Lossless?
Qualcomm made early noises about aptX Lossless two years ago. A year later, it appeared in Nura’s NuraTrue Pro IEMs. That was November 2022. But then, in April 2023, Nura was acquired by Denon to leave the NuraTrue Pro as ‘unavailable’.
Major player takeup of aptX Lossless has been thin on the ground. Last month, Bose announced that its new line of QuietComfort Ultra headphones and IEMs would support aptX Lossless; at time of writing, they are the only aptX Lossless-capable headphones listed on the Qualcomm website.
Before we click over to the iFi or Bose store on Amazon, let’s remind ourselves of three important factors:
- In environments congested with Bluetooth signals, the aptX Lossless codec is designed (like Sony’s LDAC) to drop its transmission data rate down to a lossy level in order to avoid dropouts and playback glitches. This is unlikely to happen with an iFi Neo DSD 2 used at home but take a pair of Bose Quiet Comfort Ultra to the airport and see what happens.
- Or rather, don’t. Android’s Bluetooth settings pane tells us which codec is being used but nothing about the bitrate. It’s almost impossible to observe a Bluetooth audio connection’s bitrate in real-time
- Our chosen headphone’s drivers, the DSP used to tune them (and execute any ANC), the microphones, the amplifiers and their collective implementation by the manufacturer will have a far greater impact on what we hear than the audio codec in play.
Returning to the iFi DAC, our final thought lands as a question spun off from the first of those three points: why lean on a lossless Bluetooth connection at home when a wi-fi network sidesteps 1) a Bluetooth connection’s bitrate anxiety and 2) our ongoing dependence on the smartphone to supply the stream? Google Chromecast, Plex, Roon, Squeezebox, Spotify Connect and Tidal Connect all hand the stream off to a suitably specified network endpoint to remove any dependence on the smartphone remaining in range or being powered on.
The iFi Neo iDSD 2 is available now for £899.
Further information: iFi Audio
