(Last Updated On: May 25, 2021)

A unique mix of raw, fire-breathing power and refined audio perfection in a no-frills portable package.

Thank you to iFi Audio for providing the iDSD Diablo for review purposes. If you’d like to purchase the Diablo, it is available from Amazon.

I have a riddle for you.

What do you get when you mix the incredible performance and namesake of a 90’s era Lamborghini with the sultry presence of Elizabeth Hurley in Bedazzled? A hawt new portable headphone DAC/amp from British company iFi, of course!

Yeah. That made about as much sense as the iFi iDSD Diablo did to me at first glance.

It is nothing new for iFi to release a great new portable DAC/amp. They are known for producing feature-rich and high-performing mobile devices, primarily in a subdued color palette. With price points on the lower-but-reasonable side of things, iFi devices are typically adorned with rich feature sets, including X-Bass and 3-D+ settings.

And then they released the Diablo.

The very red iFi iDSD Diablo.

iFi iDSD Diablo

"Much like a stripped-down racecar, it’s not for everyone. Still, for those who can appreciate its rare combination of phenomenal power and a lean performance-oriented feature set, the Diablo is uniquely positioned. The Diablo is unapologetically big, red, and powerful. It’s expensive, and it doesn’t have the feature set of iFi’s lesser models. But it sounds phenomenal. Take it or leave it."

Pros:

  • »Output power to put most desktop devices to shame
  • »Controlled, detailed, and dynamic sound
  • »Truly high-fidelity audio reproduction
  • »Silent background
  • »Awesome list of included accessories
  • »Decent battery life

Cons:

  • »It’s very red
  • »Too large to be pocketable
  • »Too powerful for efficient IEMs without the iEMatch+
  • »No single-ended line-level output nor analog input
  • »No Bluetooth, X-Bass, or 3D sound options

With a price tag almost 50% more than their previous top-of-the-line portable model (the micro iDSD Signature), the Diablo lacks X-Bass and 3-D+ features, sports a Ferrari red paint job, and boasts a shockingly high output power (~5W @32Ohms). Suffice to say, the Diablo is something very new for iFi.

iFi clearly sees the Diablo as their stripped-down race car model. Unbolt the passenger seats, tear out the interior carpet, and weld in a roll cage, the Diablo is all about undiluted performance and power. iFi’s marketing appears to revel in the car imagery.

“Just like a racing car designed for uncompromising speed, the iDSD Diablo sets aside sonic tailoring as well as Bluetooth connectivity to focus on pure sonic power. Prepare for a riveting ride as it will drive any headphone on the planet with aplomb…

With 3 settings, you can adjust power and gain to suit your daily driver or track day supercar!

Turbo… Normal… Eco… The iDSD Diablo’s focus on pure, unadulterated performance…

Formula 1, iFi style.” – iFi

When I first encountered the Diablo, I just couldn’t wrap my head around it. It’s got the power to drive the most inefficient headphones on the planet properly. And if there is something that those full-sized monster cans aren’t, it’s portable. So why would I want a battery-powered device to pair with them?

Also, quick to be pointed out in most discussions regarding the Diablo, is that it has fewer features than the previous flagship model and is far more expensive.

And why is it so, very, very red?

Did the Diablo win me over? Is it a ‘big bomb’ (which it physically resembles) or ‘da bomb’?

Let’s find out.

In a world full of silver, black, and brown, the Diablo stands out.
In a world full of silver, black, and brown, the Diablo stands out.

Company Overview

iFi audio is an award-winning audio tech company headquartered in Southport, UK. Since launching in 2012, iFi has focused on creating enthusiast-focused audio devices, including desktop and portable DACs, amplifiers, power conditioners, digital and USB noise filters, stereo music systems, and a variety of accessories.

iFi oversees the design, development, and manufacture of over 30 products from their UK headquarters and has a US-based distribution center and offices. Parts are sourced from across the globe, including Germany, the USA, and Japan.

Specifications

  • Form: Portable DAC/amp
  • Digital Inputs: USB 3.0 type ‘A’ (USB2.0 compatible), S-PDIF (3.5mm coaxial/optical)
  • Formats Supported: DSD512/256/128/64, Octa/Quad/Double/Single-Speed DSD, DXD (768/705.6/384/352.8kHz), Double/Single-Speed DXD, PCM (768/705.6/384/352.8/192/176.4/96/88.2/48/44.1 kHz), MQA (Full Decoder)
  • Frequency Response: 10Hz-80kHz(-3dB)
  • SNR Balanced / S-E: -120dB / -114dB
  • Dynamic Range Balanced / S-E: 120dB / 114dB
  • THD + N Balanced / S-E: 0.002% / 0.001%
  • Headphone Max Output Balanced / S-E: >19.2V/611 mW (@ 600 Ohm), >12.6V/4,980 mW (@ 32 Ohm) / >9.6V/153 mW (@ 600 Ohm), >8.8V/2,417 mW (@ 32 Ohm)
  • Fixed Audio Output Balanced: 4.4mm
  • Power consumption Turbo/Normal/Eco: 12W/5W/2W
  • Battery: Lithium-polymer 4800mAh
  • Dimensions: 166 x 72 x 25 mm, 6.5″ x 2.8″x 1.0″
  • Weight: 330g (0.73 lbs)
  • Warranty period: 12 months

Packaging

The standard iFi packaging is quite attractive.
The standard iFi packaging is quite attractive.

The Diablo is packaged in an attractive cardboard sleeve with product photos and specifications prominently displayed. Within the sleeve is a relatively large white box that contains the Diablo securely ensconced in foam. Beneath the Diablo are a couple of nested boxes containing all the accessories.

The Diablo is safely packed in black foam.
The Diablo is safely packed in black foam.

In the box

  • Diablo iDSD DAC/amp
  • iFi iPower supply 5V
  • Power Supply to USB-C adapter
  • iFi USB iPurifier3 (included with the first 1000 sold)
  • USB-A to C adapter
  • USB-A male/female cable (blue)
  • 4.4mm Pentaconn to dual 3-pin XLR cable
  • 6.35mm to 3.5mm adapter
  • Optical S/PDIF to 3.5mm adapter
  • iFi iTraveller travel case
Under the Diablo you will find the iTraveller case and generous assortment of accessories.
Under the Diablo you will find the iTraveller case and generous assortment of accessories.

Accessories

Simply wow. Now, this is an outstanding selection of bundled accessories!

Counting just the three products that iFi sells separately (USB iPurifier3, iPower supply, and iTraveller case) adds up to more than $200 worth of accessories. In a world where you struggle to find a smartphone with an included power adapter, the plethora of accessories feel genuinely luxurious.

Appropriate accessories for a TOTL product.
Appropriate accessories for a TOTL product.

I’m not going to delve into an argument regarding the functionality or promised audible improvements that using a product like the USB iPurifier3 or the iPower supply might provide. Just be satisfied that they were in the box with the Diablo. I’m happy to use them, and at worst, I feel they aren’t hindering performance in any noticeable way.

It appears that the iPurifier3 is only included with the first 1000 Diablos sold. It’s unfortunate as it is a generous add-on to find in the box.
iFi claims that the iPurifier3 uses state-of-the-art REclock, REgenarate and REbalance2 technology to eliminate jitter and distortion caused by DC offset.
iFi claims that the iPurifier3 uses state-of-the-art REclock, REgenarate and REbalance2 technology to eliminate jitter and distortion caused by DC offset.

The iTraveller case bears special mention, as it’s one of the nicest portable audio cases I’ve encountered. iFi describes it as “a multi-purpose travel case designed specifically for portable DACs,” and it’s (just) roomy enough to squeeze in the Diablo’s prodigious length. The dimensions are 135mm x 190mm x 50mm, and much like the Diablo itself, the case is portable but far from pocketable.

The iTraveller includes handy elasticated mesh pockets and removable partitions to keep your audio accessories securely in place. There are slots on the top and bottom to allow pass-through cable egress and a mesh pocket on the back to hold your smartphone or DAP. Made of grey water-resistant fabric and embroidered with the iFi logo, the iTraveller is discreet, classy, and attractive.

The 4.4mm Pentaconn to dual 3-pin XLR cable.
The 4.4mm Pentaconn to dual 3-pin XLR cable.

The Diablo also includes an unusual output cable, a 4.4mm Pentaconn to dual 3-pin XLR to support balanced analog audio output. It’s worth noting that the Diablo has no analog inputs nor single-ended output.

The Little Bear MC3 lets you use a balanced DAC output with single-ended amplifiers.
The Little Bear MC3 lets you use a balanced DAC output with single-ended amplifiers.

I recently purchased the Little Bear MC3 balanced input/output switch box, which provides three inputs and outputs (2 balanced plus a single SE). It is so useful because it passively converts a balanced signal to a pair of single-ended RCA sockets. It’s a great and inexpensive option for using a balanced-only DAC (like the Diablo) with amplifiers featuring only single-ended inputs.

I’m all about flexible solutions to resolve system incompatibilities.

A surprising omission from the generous list of included accessories is the iFi iEMatch+. This handy little gizmo is designed to “connect between your headphones/iEMs and the output… to simply and instantly improve playback…” by providing up to 24dB of noise reduction (with 0% frequency loss) to ensure a safe and comfortable listening level with sensitive IEMs and powerful amplifiers. It seems like an obvious slam dunk for the portable powerhouse Diablo.

Design

Let’s address the tomato in the room. The Diablo is RED. Did the name or the color come first? iFi is mum on the subject.

Unfortunately, the red paint job doesn’t seem as robust as the typical anodized finish found on iFi’s products. I’ve already put the inevitable first scratch in the paint with reasonably careful use.

The sturdy aluminum-cased Diablo has round sides (somewhat similar to the hip-dac silhouette), unlike the angular designs of most of their previous portable DAC/amps.

With the uniquely shaped Zen and NEO iDSD recently added to the lineup, iFi is apparently experimenting with product design. Their lineup is no longer immediately recognizable as belonging to the same manufacturer. There are some hits and misses in there, with the NEO decidedly a design standout and the Diablo falling somewhere mid-pack.

The simple controls on the Diablo's front face.
The simple controls on the Diablo’s front face.

The front face has two headphone outputs (6.35mm SE and 4.4mm balanced), a 3-position gain switch (Turbo, Normal, Eco), a large but subdued indicator LED, and a combined power/volume knob.

LED indicator

LED ColorPlayback Format
YellowPCM 48/44.1kHz
WhitePCM 768/705.6/384/352.8/192/176.4/96/88.2kHz
CyanDSD 128/64
RedDSD 512/256
GreenMQA
BlueMQA Studio
MagentaOriginal Sample Rate (MQA)
If you update the Diablo to the iDSD Diablo – Firmware 7.0c – GTO Filter / MQA / DSD256 (Sub-version) firmware version, all PCM LED colors will be the same due to the GTO filter.
The rear panel has an unusual assortment of connections.
The rear panel has an unusual assortment of connections.

The rear face has iFi’s standard recessed male USB-A data input socket (that allows for easy compatibility with the Apple Camera Kit), USB-C power/charging socket, tiny charging status LED, 4.4mm Pentaconn balanced analog output, and 3.5mm S/PDIF digital input.

The battery LED changes color to indicate full (white), partial (green), or low (red) charge status. A full charge takes about 6 hours, while runtime varies depending on the gain setting, Eco (8-10 hours), Normal (6-8 hours), or Turbo (3-5 hours).

It’s an unusual but straightforward layout of controls and inputs/outputs.

Display? Nope. Single-ended analog outputs? Uh-uh. Analog input? Yeah, no. Rubber feet on the bottom? Fine, you can have four.

Internals

Like any good, err… evil demon, the Diablo is purposely deceitful. The simple exterior obscures hidden depth and complexity. While this may sound like a summary of questionable dating decisions, the devilish Diablo turns out to be beautiful inside.

As the old adage goes, ‘it’s all about the music.’ The Diablo walks the talk. iFi goes to great lengths to assure potential purchasers that all decisions were purposely made in the Diablo’s design to maximize the highest quality of music reproduction. The Diablo is a purist’s device, and the race car driver doesn’t lament the lack of air conditioning to maximize performance.

The xDuoo 05BL Pro Bluetooth add-on plugged into the digital input on the Diablo.
The xDuoo 05BL Pro Bluetooth add-on plugged into the digital input on the Diablo.
While Bluetooth is not included with the Diablo, the inexpensive and oh-so-useful xDuoo 05BL Pro module works great connected to the S/PDIF input (just like it does with the Chord Mojo) to bring a high-quality Bluetooth connection to a device not designed for it.

The Diablo uses dual Burr-Brown DAC chips mated to a new 16-core XMOS chip to handle bit-perfect decoding up to PCM 768, DSD 512, and 2xDXD. iFi has jumped with both feet into MQA support and created the optional GTO digital filter (changeable via firmware updates) in conjunction with the MQA team. The GTO filter measures almost identically to the proprietary MQA one.

The MQA logo is featured prominently on the Diablo's box.
The MQA logo is featured prominently on the Diablo’s box.

After trying both available filters, I find I prefer the sound of the standard Firmware 7.0 – MQA / DSD256 (Cookies & Cream) filter. The following testing and listening impressions are all based on this firmware with the Diablo.

MQA is a super contentious topic right now and worth reading what the controversy is all about.

iFi calls their new, balanced, symmetrical dual-mono circuit design PureWave. It focuses on short, direct signal paths to achieve “exceptional linearity and infinitesimally low levels of noise and distortion.” OptimaLoop is their name for employing multiple optimized negative feedback loops in the amplifier circuit to more accurately control gain and further reduce distortion.

Additional topology enhancements include employing DirectDrive (no coupling capacitor design), MOSFET muting via micro-controller, jitter reduction via a GMT (Global Master Timing) femto-precision clock, TDK C0G (Class 1 ceramic) capacitors, Panasonic OS-CON capacitors, muRata capacitors, and Vishay MELF resistors.

Under the Diablo's hood. (From: ifi-audio.com)
Under the Diablo’s hood. (From: ifi-audio.com)

While there’s an unarguably impressive bunch of technology under the hood, what jumps off the specs page is the sheer, unadulterated power of this little devil.

With a maximum power rated at 32Ohms of 4.98W (balanced) and 2.5W (single-ended), the Diablo is in a class of its own as far as portable amplifiers. Heck, it puts most desktop devices to shame (I’m looking askance at you iFi NEO iDSD).

Do you have super-demanding, power-hungry, inefficient, and high-impedance full-sized cans that scoff at portable amplifiers? Do you wish you could listen to them in all their glory at the grocery store? The Diablo is the answer to your dark prayers. You can lay off the midnight chanting, pentagon drawing, and small creature sacrificing because iFi has delivered the goods.

iFi iDSD Diablo Sound

Since this is a portable device, I started my testing using highly efficient IEMs. As expected, pairing the Diablo with the Thieaudio Monarch IEMs, even on the lowest gain setting (Eco), there is almost no usable range on the volume control. From silent to way-too-loud in only a few degrees of turn. No great surprise.

I splurged and ordered the iFi iEMatch+ device to see if it delivers on its promise of significant volume reduction without a noticeable impact on sound reproduction. It turns out, my initial thought that this should be included with the Diablo was right on the nose, and I highly suggest anyone purchasing a Diablo to add one of these little adapters to their order as well.

The IEMatch works well to tame the power of the Diablo for use with sensitive IEMs.
The IEMatch works well to tame the power of the Diablo for use with sensitive IEMs.

With the iEMatch+ switch on the Ultra setting and the Diablo set to Normal gain, the Monarch have about a half-turn of usable volume range. Far more tailorable and with much less chance of catastrophic IEM or eardrum damage due to unwanted gain changes or accidental volume knob manipulation.

As far as how the Monarch sound with the Diablo? Superb.

The Diablo delivers a silent background, extraordinary dynamics, and a very impactful yet clean sound. It’s energetic and immaculate sounding without being sterile or dry. And all these admirable qualities apply to any pair of headphones I tried with the Diablo. From the humble Koss KPH30i, to the luxurious Ultrasone Edition 15 Veritas (and many in between), the Diablo drives them all to their potential best.

iFi incorporated some internal trickery to make the Diablo work properly with difficult to drive headphones such as planar magnetics. Folks often mistakenly believe that lower-powered amplifiers will properly drive planars due to their fairly low impedance and higher sensitivity ratings, but planars need power for proper playback and control.

“In order to make less efficient headphones, like planar magnetics, sing, the voltage needs to be stepped up from 3.7V to +/- 15V. We use a step-up converter running at 1.2MHz – a frequency far beyond audibility that is easier to filter than a typical switch-mode supply, enabling high linearity and ultra-low noise.” – iFi

In fact, the Diablo has taken over desktop solid-state amplification duties for me.

I’ve found myself auditioning several solid-state desktop amplifiers lately and being discouraged by one aspect or another. The output power, price, or design compromises always seem to keep me from finding the right one for my wants and needs.

When the Diablo arrived, I didn’t even consider it as a desktop amp contender. Obviously, it’s portable, that’s why it’s got a battery! But after auditioning the Diablo, I found my desktop powerhouse in a small (for a desktop device) red package.

I created a useful cable to connecter the USB-C connector on the Hidizs AP80 Pro to the Diablo's male USB-A socket with a Audioquest DragonTail and a USB-A to C converter.
I created a useful cable to connecter the USB-C connector on the Hidizs AP80 Pro to the Diablo’s male USB-A socket with a Audioquest DragonTail and a USB-A to C converter.
Perhaps ironically, the Diablo has not supplanted my favorite portable setup, the tethered combination of a Hidizs AP80 Pro DAP and Chord Mojo DAC/amp. I love the sound profile, and their far more portable and pocketable size keeps them in the winner’s circle. A device’s physical dimensions are a crucial part of mobile usage, and the Mojo is more than capable of driving any pair of headphones I would consider wearing in public.

Properly delivered power yields a muscularity to the Diablo’s sound and allows for control and outstanding definition when reproducing the entire sound spectrum. This is especially evident in bass layering and definition. Transients are delivered effortlessly, and the Diablo has a similarly energetic yet well-mannered sound that better desktop setups can provide.

Frankly, this is an exceptional high-fidelity headphone DAC/amp regardless of its classification – portable or desktop.

The DAC and amplifier synergy is clear, with neither side of the combo detracting from the other. Unlike with the NEO, iFi got the balance right with the Diablo. This is an excellent, smooth-sounding DAC mated to abundant, clean, and controlled power.

The Burr-Brown DAC is on the warmer and less clinical side of things than most ESS Sabre chipset-based implementations. Using the balanced analog outputs to feed an external amplifier, the DAC section of the Diablo proves to be no slouch, even without the impressive internal amp backing it up.

Beyond a massive power increase, I didn’t find any notable differences in sound quality between the single-ended and balanced outputs. Both sound excellent.

Where to Buy

Conclusion

Does power corrupt, or (as Spidey says) does it just bestow responsibility? While iFi saddled their latest creation with the Diablo moniker, it seems they accepted their sonic responsibilities with reverence. No, they didn’t make the audio equivalent of the King of Darkness. Instead, they released a refined and (dare I say) angelic sounding device.

Since it’s painted the color of Liz Hurley’s outfits in Bedazzled and packs the horsepower of a Dodge Demon muscle car, the Diablo is iFi’s most loud and proud product they’ve ever produced. It’s far too cumbersome for a pocket, entirely overpowered for sensitive IEMs, and is targeted to compete with the best portable audio products in the world. And, at first, I struggled to understand its intended market and purpose.

The diablo is a unique product in the portable personal audio market.
The diablo is a unique product in the portable personal audio market.

In the end, the Diablo didn’t care if I understood it. Much like a stripped-down racecar, it’s not for everyone. Still, for those who can appreciate its rare combination of phenomenal power and a lean performance-oriented feature set, the Diablo is uniquely positioned.

It took a while, but finally, I got it.

The Diablo is unapologetically big, red, and powerful (I’m getting Hellboy flashbacks). It’s expensive, and it doesn’t have the feature set of iFi’s lesser models. But it sounds phenomenal. Take it or leave it.

I’ll take it.