It is the summer and time for holidays, and a little more portable or travelling headphone capability is required. With the sad departure of the ‘Editor’s Pick’ GO Bar Kensai that has gone back to the reviewing place in the sky, it is time to trade up to the iFi Audio iDSD Diablo 2 headphone amplifier, which is undoubtedly less portable than the ‘donglely’ Kensai but no less vibrant on the move and in the ear.
Design
The iFi Audio iDSD Diablo 2 headphone amplifier (henceforth referred to as the Diablo 2) has so much in it. I will highlight some key areas; the full specification is linked below.
The Diablo 2 features an XMOS 16-core chip that processes the audio data received via the USB digital input. It has the latest Qualcomm QCC518x Bluetooth 5.4 chip, which supports aptX Lossless, aptX Adaptive, aptX, LDACTM, LHDC/HWA, AAC and SBC. It also has full MQA unfolding if you like that. The DAC chipsets are Dual Core Burr Brown, as used in the Pro iDSD (though this is Quad Core).
The Diablo 2 can be run with a mains USB-C adaptor or on a lithium-polymer 4800mAh Battery.
Its inputs are a 4.4mm balanced input, S/PDIF 3.5mm coaxial or optical, USB C, and Bluetooth. If you have it, the output is to a 4.4mm balanced/xMEMS output, or the iFi pseudo balanced 6.35mm output.
The frequency response claimed in Line mode (is this just analogue?) is an astonishing 1.5Hz-400kHz (-3dB), and the DAC response is similarly spectacular and certainly unhearable for most humans (1.5Hz-114kHz (-3dB)). The claimed signal-to-noise ratio is also an ‘off the scale’ 114 dB. The continuous power output is claimed to be well over 2000mW in balanced or single-ended modes, which is similarly spectacular. This all adds up to anticipated punch and power and offers a solution to a full range of power-hungry headphones.
Quality
This aluminium case’s industrial red/grey matt finish is top-end. It has a reassuringly heavy feel that hints at rucksacks on the move rather than trouser pockets. On the desktop, the included slide-on ‘wings’ angle the unit upwards, improving button access.
The on/off volume knob is bevelled and delicious, and there is a lovely volume lock for on-the-move listening. Similarly, the Nitro switch is recessed so that you don’t accidentally blow your ears off on the move.
The Diablo 2 is 166 x 85 x 28.5mm (L x W x H) and weighs 455g (1.0Ibs). It is currently priced in the UK at £1299.
The full specification is here.
Performance
Review Equipment
I’ve been listening to the Diablo 2 with a pair of Meze Audio ADVAR IEMs, the Meze 109 Pro over-ear headphones and the FiiO FA19 IEMs on a recent flight to Portugal (and back).
Physically
The machining of the Diablo 2 is quite sharp and angular. I have not physically had the original Diablo, but when I saw it at the Northwest Audio Show, it appeared to be smoother and softer to the touch. The Diablo 2 has a real feel of high quality with weight and balance.
Although I do not have any high-impedance headphones here, I have no need for the Turbo mode, let alone Nitro mode, both of which are offered for power-hungry headphones. My open-backed 50 Ohm Beyerdynamic 990 Pro Xs were beautiful but certainly did not need a Turbo or a power output boost in any way. The volume knob barely got over mid-way from the “7 o’clock” starting ‘ON’ point in my ears.
Speaking of volume, I find the first few 10-15 degrees of volume on the control to have no output. However, this is the only problem I have found with the Diablo 2. The IEM Match, in this context, does not seem to affect this as I thought it might. Maybe this is a safety thing?
The volume lock, I guess for rucksack use, is pristine, beautiful, and without fault.
The provided wings are good for creating an angle on the desktop, and the rubber feet also provide grip.
The battery does take a while to charge, but overnight is fine for me. The battery is big, I guess. It might be easier if the charge light on the back under the USB-C lead was at the front.
FiiO FA 19
…resolution and foot-tapping joy
These FiiO FA10 in-ear monitors are very easy to drive (just 10 Ohms claimed impedance with 10 (yes TEN) balanced armatures); using the 4.4mm Balanced Output fitting on these headphones, nothing is being left behind by either the FiiO IEMs or the Diablo 2. Beck’s heavenly Morning (Qobuz 24-bit, 96kHz) has a beautiful bass line, and Oasis’ Live Forever (Qobuz 24-bit, 44.1kHz) has similar bass control from the Diablo 2. Searching for soundstage, Bowie’s Song for Bob Dylan (Qobuz 24-bit, 96kHz) does it for me (and I can crank it up a bit). Here, the stage is forward and centred, and it rolls through perfectly. The balance of vocal and piano is clear and crisp. The left-right image (mix) in Bowie’s Soul Love (Qobuz 24-bit, 96kHz) is similarly engaging. For guitars and detail, look no further than Stick Season (Qobuz 24-bit, 96kHz) for a bit of resolution and foot-tapping joy.
Meze Audio 109 Pro, Beyerdynamic DT900 Pro X
… a premium desktop listen
Around halfway through the process, I realised the LED at the front indicates the quality of the streaming source, indicating sample rate or DSD, etc. MQA works nicely with that vivid Blue for MQA Studio.
The 109 Pros are always a delight to listen to, and with this high-quality headphone amplifier, they are a premium desktop listen.
Bluetooth
The Bluetooth works well, and I have no reason to doubt the quality on offer. If I am honest, I fail to see the need for Bluetooth at this price point, though I do understand why it is there for completeness. aptX Lossless is hard to find in these kinds of devices and, if I may say so, harder to source. If you have an iPhone, forget it (atm).
Musical Interlude
Here’s the Musical Interlude Playlist on Qobuz. Here’s the sweltering 30-degree Portugal Playlist on Tidal.
Thoughts
This is a quite flawless package
This is a quite flawless package. Even if you ponder the price, this is a real long-term investment. Thoughts inevitably turn to the Chord Mojo 2 (£395), which is similar but different in inputs and outputs, as is the peerless Hugo 2 (£2100), which needs a USB C upgrade in 2024. If budget is the issue, the Mojo 2 is the winner, and if you’re after the ultimate audio desktop experience, then the Hugo 2 takes the prize, but this Diablo 2 is a decent middle option.
It is hard for me to think you would want to buy this for the Bluetooth capability when you could just as easily buy a GO Blu and still have £1150 in your pocket. In the same way, you could buy the iFi Audio hip-dac 3 for similar, though reduced, performance, without the Bluetooth, and pocket yourself £1100.
Overall
As I often say, if this is your budget and you’re on the move, then why not? It is an investment. The package as a whole is quite compelling in this very competitive space. It feels quite hard not to recommend it if this is your price point.
Quality build
Styling
Sonic signature
Like
Multiple inputs
The ‘wings‘
Wish
The low volume sensitivity was more accurate
Battery light was on the front instead of the back
Specification
Full details are on the company’s site.
Where to Buy
iFi Audio iDSD Diablo 2 Portable DAC / Headphone Amplifier at Future Shop* here
*This is a sponsored link