Best headphone amplifiers of 2024, tested for pristine sound

Best for: An audiophile experience

Going straight in at the top with a no-nonsense, utter powerhouse of a home amp at an equally no-nonsense price, the Niimbus US 5 Pro from Violectric is one of the most powerful headphone amps available, capable of driving even the most demanding dynamic and planar headphones with ease. This is thanks to a cutting-edge pre-gain setting featuring a wide control range from -18 to +24 dB, 4x powerful amps offering an output of 7000mW Pmax into 50-Ohm and 32V RMS into 600-Ohm, plus a high damping factor.

What does that mean? In a nutshell, flawless signal amplification, complete crystal-clear clarity, and an utterly immersive experience.

A large number of inputs and outputs imbues the US 5 Pro with all the flexibility of a contortionist, including 2x unbalanced 6.3-millimeter-jacks, plus 4-pin-XLR- and 4.4-mm-Pentaconn-connections for balanced headphones, so all audio ear-defenders are catered for.

Undeniably elegant on the eye, too, the Violectric Niimbus US 5 Pro is the pinnacle of headphone amplifiers, constructed from only the finest cutting-edge components and capable of purity and detail perfection.

Does it come at a hefty price? Why, yes it does, but for the audiophile who wants it all, it pays to go Pro.

Best for: Portable play

Heading to the other extreme now in terms of price and size, the pocket-sized portable KA17 DAC/amplifier from FiiO is your affordable entry to enhanced audio on the move. Featuring dual flagship ESS ES9069Q DACs, THX AAA 78+ amplification, and a 16-core XMOS XU316 USB SoC (System on Chip), the diminutive device delivers up to 650mW of output power (Desktop mode) and offers full support for 32-bit/768kHz, MQA, and native DSD512 Hi-Res audio files.

Playing nice with the likes of Android, iOS and your PC, despite its diminutive dimensions, the KA17 still manages to feature both Single-ended 3.5mm and Balanced 4.4mm headphone outputs, the former supporting SPDIF output. And, to that end, all you have to do is plug in your cans and you’re good to go.

Controllable via the natty 0.9-inch dot-matrix display screen, there’s also a FiiO Control app for Android and iPhones which lets you alter Gain to High or Low, play around with 8x Filter modes, and fiddle with the 10-level Parametric EQ, and adjust volume and screen brightness.

Beautifully built, too, and finished in anodised aluminium, the KA17’s performance is flawless, raising audio to whole new levels, whether you’re listening from your special ‘listening chairs’ at home or trundling along on the Tube.

Best for: Audio boosting on a budget

Fancy pocketing a Balanced & Single-ended mini DAC and amp for under a ton? Of course you do, which is why I want to show you this, the S9 PRO from HIDIZS is another portable option that offers up an ESS9038Q2M DAC and PCM support up to 32bit/768kHz for high res audio playback from your phone that elevates quality to whole new heights of clarity, with stunningly tight bass and lovingly balanced mids and treble.

Capable of driving all manner of headphones, the S9 PRO delivers 100mW into 32-Ohm (3.5mm SE) and 200mW into 32-Ohm (2.5mm Balanced) and supports iOS, Windows, Android, Mac OS and iPad OS for a true all-devices enhanced audio experience.

Made from aluminium alloy and small enough to stick in that weird jeans pocket that normally serves no purpose, the HIDIZS S9 PRO is a seriously powerful DAC dongle that brings the desktop headphone amp experience to the streets.

Best for: Audiophile-level enhancement at a lower cost

My second pick from the vast array of headphone amps that FiiO offers is the flagship R9, and it’s as mighty in ear action as it is easy on the eye. Launched at CES 2024, this is a desktop headphone amp that’s got the lot, including dual high-performance 8-Channel ESS Sabre ES9038PRO DACs and high-power 8-Channel THX AAA 788+ desktop-grade amplification, allowing it to deliver up to 7300mW of power output.

Boasting an absolute embarrassment of inputs and outputs, including HDMI ARC, the FiiO R9 is the perfect partner for all manner of devices, including headphones both wired and wireless, smartphones, PCs, and even active speakers.

With support for high-res PCM up to 768kHz/32-bit, native DSD512 audio, and MQA decoding, the R9 even comes with 4GB of RAM and 64GB of storage (expandable to 2TB with SD card), so you can store your tunes onboard, or stream from all the usual streamy suspects, such as TIDAL, Amazon Music, Spotify, Deezer, Soundcloud, Apple Music, Qobuz, and others, all of which can be installed directly.

Sound quality is, as you might expect, second-to-none in the soundscapes created, powerful, beautifully transparent and utterly uncoloured, from any source – enough to make you fall in love with audio all over again.

Finally, a full-HD, full-colour 6-inch display makes the R9 easy to control and, yes, also stunning to behold and deserving of pride of place on your desktop.

Best for: Devilishly good sound

Now, if you want headphone amp power both at your desk and on the move, but don’t have the spare spondoolicks to splash out on two different amp options, then prepare to part with a grand and two ton for a remarkable hybrid headphone enhancer that is happy to work at home or in the wild.

Yes, this is the DSD Diablo 2 from the award-winning audio tech company iFi, DAC/Amp that offers the best both home and away thanks to its power-packing 5180mW maximum output and balanced dual-mono circuitry, two facts that the little devil the most powerful headphone amp of its size.

Coming complete with Bluetooth 5.4, the Diablo supports aptX Lossless for CD-quality audio over Bluetooth, while the Dual Core Burr Brown chipset provides Full MQA decoding, DSD512, and Bit-Perfect DSD and PCM support at rates up to 768kHz.

Naturally, the Diablo can be run by mains on the desk and by battery on the move, the included iPower 2 power supply features a step-up voltage converter to assist and enhance less efficient cans, and also Active Noise Cancellation II to ensure no incoming EMI and RFI noise interferes with your listening pleasure.

Hooking up with headphones of all manner, you’ll find a 6.3mm Single-ended socket and a 4.4mm Balanced output. Additionally, a 3.5mm to 6.35mm adapter is included for complete connection versatility. Round the back, meanwhile, you’ll find USB-C S-PDIF (3.5mm coaxial/optical) inputs too.

Damn fine looking, to boot, with an aluminium enclosure finished in Devilish Red, the Diablo 2 weighs in at around 0.5kg and measures 6.5 x 3.3 x 1.1-inches, making it easy to carry around with you, which is very much the point and another box ticked.

An extremely powerful DAC/Amp that’s good to go on the desk or on the move, the iFi iDSD Diablo 2 is one Beast of headphone booster.

Best for: Kicking tunes from a keyboard

Something a bit different now, behold the KB3 from FiiO, a doubly useful device that is a customisable wireless mechanical keyboard, compatible with Windows, MacOS, Android and iOS, that also happens to have 2x high-performance and efficient CS43131 DACs, as well as two low-noise SGM8262 op-amps built in.

What this means is that you can now enjoy enhanced audio while you work or play, with 550mW of output power literally at your fingertips. Supporting audio files up to 32bit/384kHz and DSD256, and equipped with 3.5mm Single-ended and 4.4mm Balanced headphone outputs, the KB3 is open to use with the majority of headphones, driving them to better things like the devil were on its tail.

Also featuring semi-transparent swappable keys with multiple RGB light presets available, the KB3 looks as good as it makes your music sound. So, if you’re not taken with any of the other headphone amp options I’ve presented here, perhaps this one is more your – ahem – type.

Best for: top end

Another epic top-end amp but for a considerable chunk less cash than the Violectric, the iCAN Phantom has a classic aesthetic, almost looking like two separate units, the top being a slick means to control, complete with OLED display, and the bottom section offering ample inputs and outputs both front and back.

Featuring two input stages, one valve/tube-based, and the other solid state, you can switch between the two in real-time, which means you can enjoy the pace of solid state, the free-breathing fluidity delivered in Tube mode, and the absolute warmth added when you switch to Tube+.

Incorporating iFi’s standalone iESL energiser technology with regular amplifier technology, the iCAN Phantom welcomes every type of headphone with 1x 3-pin balanced XLR (L/R), 1x 4-pin balanced XLR, 1x 4.4mm balanced, 1x 6.3mm (positive phase), 1x 6.3mm (inverted phase) and 1x 3.5mm (includes S-Balanced technology to cut distortion by 50 per cent) outputs, delivering more than a ruddy ridiculous 15,000mW from its Balanced outputs and more than 5760mW from its Single-ended outputs in a 16-Ohm load.

Incredibly powerful, incredible looking, and incredible to ear-inhale, sound quality breathes transparency, clarity, purity and balance throughout, leaving you in no doubt that the entry price into its world was money well spent. Indeed, when it comes to performance perfection in luxury headphone amplifiers, the iFi iCAN Phantom is the Rolls Royce Phantom.