iFi audio GO bar Ultraportable DAC & Headphone Amplifier review

British hifi manufacturer iFi Audio has released yet another portable audio device that’s designed to give headphone listeners audiophile-quality sound, in an incredibly portable package. The new $479 iFi audio GO bar Ultraportable DAC & Headphone Amplifier is an all-in-one USB DAC and headphone amplifier and packs a stunning 475mW of power into its tiny thumb-sized chassis. And when I say “tiny”, I really do mean it: the GO bar weighs in at a mere 28.5 grams. 

Does this too good to be true? We’d better dig in and see if the diminutive iFi GO bar really is a giant killer. 

Why we need to talk about your phone 

Any device that turns the 1’s and 0’s of digital audio back into the analogue stuff that you and I call “music” has a digital-to-analogue converter or “DAC” inside it. Your smartphone has one. Your laptop has one. There’s one in your car, and there’s probably one in your watch too. The problem is, however, that these DAC chips are churned out by the million and probably cost less than a buck each to make en masse. It’s not all that surprising then, that the DAC in your smartphone doesn’t really sound all that crash hot. 

If you’re one of the few remaining people lucky enough to have a phone with a headphone jack, then you’ve technically got yourself a headphone amplifier too! But yep, you guessed it - it’s a pretty crook one, and is probably only capable of outputting a few milliwatts of power, and is also contaminated with all sorts of noise and distortion from all that other “phone stuff” your phone needs to do. 

So while we’ve established that your average smartphone isn’t exactly designed with the hifi enthusiast in mind, they are also incredibly useful devices when it comes to searching, streaming and enjoying all sorts of content, including music. And seeing as you can pretty much manage your whole life using the one device that you’re reading this article with, it’s no wonder that many people couldn’t really be bothered adding a completely separate device into their repertoire. 

Enter the “dongle” 

In the last five or so years we’ve seen the entry of the “dongle DAC” into the personal audio market. These devices can provide you with an immediate upgrade over the audio circuits inside your smartphone (or laptop/PC) by completely bypassing them - your smartphone hands off the digital signal via a USB cable to the “dongle” device, which has a far more capable DAC chip and amplifier circuit inside. And seeing as these USB-DAC devices are generally no bigger than your thumb, you’re really not adding much by way of weight or bulk at all - just significantly better sound. 

Meet the iFi GO bar

Coming hot on the heels of the recently-launched iFi Audio GO blu Mobile Bluetooth Headphone Amplifier, iFi has added another entrant to their ultraportable “GO” range with the launch of the brand-new iFi GO bar. Yes, it’s a “dongle”-DAC, but not as you know it. With a single-ended 3.5mm and a fully-balanced 4.4mm headphone jack, the GO bar can manage to push out an extremely potent 475mW of headphone-driving power (this drops down to a still respectable 300mW from the 3.5mm output). Having just under half a Watt of power in this style of USB device is previously unheard of, and in fact, iFi is calling the GO bar “the world’s most powerful headphone amp of its size”

The GO bar does seem way too small to be packing this much by way of output, with an exceptionally tiny 65mm x 22mm x 13.2 mm frame that weighs practically nothing - 28.5 grams is barely enough to use it as an effective paperweight! While the GO bar could easily be mistaken for a USB storage drive at a passing glance, it’s actually a terrifically well-made little device, being constructed from a matte dark-grey aluminium. The “bottom” plate of the GO bar contains a series of lights to inform you what sample rate of PCM music you’re playing (anywhere from standard 16-bit/44.1kHz right up to 32-bit/384kHz), native DSD 64/128/256, or even MQA, with which the GO bar is fully compatible. 

There are also two additional lights on the bottom of the GO bar, which indicate whether you’ve chosen to engage two familiar iFi features: “XSpace” and “XBass+”. These are both analogue systems that let you choose to add a speaker-like “holographic sound field” or an additional bump in bass presence respectively, depending on your headphones or listening preferences (you can also have them both engaged at once). These modes can be toggled by pressing a button on the “left” side of the GO bar, which is also used to switch between four built-in digital filter options (with a longer 2-second press) that allow you to slightly tinker with the sound of the GO bar’s “Bit-perfect DSD & DXD DAC by Cirrus Logic” chip. The four selectable filters are as follows:

  • Bit Perfect​ – no digital filtering, no pre or post ringing​
  • Standard – modest filtering, modest pre and posting ringing​
  • Minimum Phase​ – slow roll-off, minimum pre and post ringing​
  • Gibbs Transient Optimised  minimum filtering, no pre-ringing and minimum post ringing​

And speaking of buttons, the GO bar actually has volume buttons - something that “dongle” DACs often eschew in favour of you managing volume levels via your source device. It’s a far better and more tactile experience having proper volume buttons that give you better and quicker control - especially if your phone’s screen is locked or if you’re simply reaching into your pocket. Mashing down both volume buttons at once for two seconds allows you to enter “turbo” mode, which provides an additional +6dB boost in gain, which is helpful when it comes to dealing with harder-to-drive headphones. 

Another feature present on many portable-oriented iFi products is their proprietary “iEMatch” system, which can be switched on with either of the GO bar’s headphone outputs via a selector switch. iEMatch is designed for use with IEMs in particular and works by attenuating the volume level to reduce the noise and hiss that can be present in more sensitive earphones. With the overall sound pressure level reduced by a few decibels, this gives the listener more usable volume range and iFi explains that this results in more dynamic range as well as overall audio quality. 

iFi GO bar key device specifications:

Input: USB-C

Formats:

  • PCM 44.1/48/88.2/96/176.4/192/352.8/384kHz
  • DSD 2.8/3.1/5.6/6.1/11.3/12.3MHz
  • DXD 352.8/384kHz
  • MQA Full Decoder

DAC: Bit-Perfect DSD & DXD DAC by Cirrus Logic

Headphone Outputs:

  • Balanced: 4.4mm
  • UnBAL: 3.5mm

Power Output:

  • Balanced: 475mW@32Ω; 7.2V@600Ω
  • UnBAL: 300mW@32Ω; 3.8V@600Ω

Output Impedance:*

  • Balanced: <1Ω
  • UnBAL: <1Ω

SNR:

  • Balanced: 132dBA
  • UnBAL: 108dBA

DNR:

  • Balanced: 109dB(A)
  • UnBAL: 108dB(A)

THD + N:

  • Balanced: <0.002% (6.5mW/2.0V @ 600Ω)
  • UnBAL: <0.09% (100mW/1.27V @ 16Ω)

Frequency Response: 20Hz - 45kHz (-3dB)

Power: <4W max.

Dimensions: 65 x 22 x 13.2 mm (2.6" x 0.9" x 0.5”)

Net weight: 28.5g (1.0 oz)

Unboxing the iFi GO bar

The GO bar, as you’d expect, comes in a suitably small white box along with a generous amount of included accessories for a device this small. iFi makes some of the best-in-market “on-the-go” USB cable adapters, and two are provided with the GO bar. A short USB-c to Lightning cable is provided for iPhone users, and a USB-c to USB-c cable ought to cover pretty much all other modern smartphone users in 2022. A handy USB-c to full-size USB adapter is also provided to connect the GO bar to Macs and PCs with older-style USB connections as well. 

To keep your fancy new dongle protected, iFi has thoughtfully included a leather pouch to house the GO bar in when you’re not using it. It also has a loop on the back so you can attach it to your belt - no doubt handy when you need to be “quick on the draw” and get listening in a hurry!

As well as a warranty card, a helpful and comprehensive instruction card is provided to help you navigate the GO bar’s fairly substantial array of features. It is essential reading, as you couldn’t otherwise know that there was a “turbo” volume mode or switchable digital filters just by looking at the device. 

iFi GO bar user experience 

The GO bar is an extremely simple device to use both from the get-go and on a day-to-day basis. After getting myself acquainted with its features and interface, it really was a simple case of plugging it into either my Pixel 6 or Macbook via the provided USB-c > USB-c cable, and off I went. 

Using my Pixel and my usual listening app, Qobuz, all audio was immediately routed to the GO bar, and all I had to do by way of adjustment was turn the volume up or down via the +/- buttons. If I chose a 96kHz or 192kHz hi-res file, the lights on the bottom of the device lit up accordingly to confirm that the GO bar was indeed processing them at the correct sample rate. The GO bar gets ever so slightly warm after playing for a while - it’s never alarming, but it does give you a nice reminder that it’s a potent little device with plenty of juice under the hood. Battery drain on my phone felt pretty negligible, even when using the GO bar in “turbo” mode - I experienced about an 8-9% reduction in battery capacity after about an hour of playback, which isn’t much more than general screen-on usage.

With the GO bar connected to your phone, you might find it a little cumbersome having it wobble around underneath suspended by the OTG cable, and I suspect that many owners will no doubt use velcro or some kind of ingenious 3D-printed connector to keep the little dongle firmly attached to the back of their phones. If you find yourself comfortably sitting down to enjoy a bit of listening on a plane or cafe, for example, then having the GO bar lying down on a flat surface won’t cause any problems at all. 

The GO bar is surprisingly great to use as a “desktop” DAC/amp when hooked up to a laptop. Selecting it as my output device in Roon, it kept the GO bar within arm’s reach to use it as a much more tactile and precise volume control device than controlling it digitally via my Mac. Being as small as it is, you’ll probably find that it’ll slide around if you have it parked on a glossy surface as the GO bar doesn’t have any rubber feet. I overcame this by simply parking it on a book or a rubber coaster. 

And of course, you don’t need to just use the GO bar as a headphone amp - with a great hi-res PCM, DSD and MQA-compatible DAC on board you can easily use it as either a single-ended or balanced DAC (or preamp, for that matter) upstream of other devices such as a pre/power amplifier or a pair of powered speakers. 

Overall, I was thoroughly impressed with how easy and enjoyable the GO bar is to live with as a day-to-day device. If you’re travelling lightly, all you need to do is slip it into your pocket, your headphone case (or even your IEM case!) and you can take a superbly-capable hi-res device to enjoy first-rate sound, wherever you find yourself. It would be nice to have play/pause and track forward/back controls on the device, but beggars can’t be choosers when you have these many features and this much power in a device this small!

Listening to the iFi GO bar

The GO bar didn’t emit so much as a skerrick of hiss or noise with the 8-ohm impedance 64 Audio U18s Universal In-Ear Earphones, and with its comfortably low output impedance of less than 1-ohm (in both output jacks), I didn’t hear any unfamiliar changes to the silky-smooth voicing of the 18s and nor did I need to engage the iEMatch feature. Without any unwanted noise or wonky frequency response bumps to spoil the party, all that was left was glorious, detailed and transparent sound. Fleet Foxes’ White Winter Hymnal sounded positively vast and expansive, with the church-like reverb in the vocal parts ringing out with sensational air and resonance. 

I always use saxophone recordings to get a feel for how natural a device sounds, and Bob Reynold’s Quartet record is a brilliantly-recorded example of showing off the tenor sax in all its human-like texture and emotion. By the time I’d gotten into the groove of track #6, Sway, I’d gotten the impression that the GO bar has the same slightly rich presentation that I’ve come to expect from other iFi Audio digital devices - despite opting for a Cirrus Logic chip over their more commonly-used Burr-Brown DAC, the GO bar sounds lush and thoroughly enjoyable - it’s certainly not a stark, warts-and-all voicing that can otherwise leave you feeling a little emotionally-detached from the process. 

Satisfied with its IEM-driving prowess, I decided to see how the GO bar fared with a proper pair of full-sized headphones in the form of the Focal Clear Open Back Headphones. I came across the 2011 record Kaputt from Canadian solo artist Destroyer (the musical alter ego of Daniel Bejar) a few years ago, and it’s been a staple in my gear-testing playlist for a while now thanks to its great production, arrangement, and general song-craft. The GO bar has oodles of power for getting a properly tight performance out of the 55-ohm/104dB dynamic drivers in the Clear, and the bass line in Downtown slapped with all the dynamic drama that I’ve come to expect from the Clear. The Clear can teeter onto the slightly brittle side of things when it comes to amp pairing, but the tone of the upper mids and treble sounded landed squarely in the “Goldilocks” zone when paired with the GO bar. I could happily pop the GO bar into the Clear’s clamshell case, pop the case in my work bag, and spend Monday to Friday happily enjoying this pairing with 8 hours of music a day while parked in front of a computer - and I didn’t even feel the urge to once switch it into “turbo” mode. 

Wanting to stretch the legs of the GO bar a little more and make use of that 4.4mm balanced output, I turned on “turbo” mode by pressing both volume buttons and settled down for a listening session with the 300-ohm/102dB Sennheiser HD800s Audiophile Headphones. I’ll say without hesitation that the GO bar has the juice to power the HD800s to ear-bleeding levels, with headroom still on top of that. Dio’s Holy Diver is one of my favourite proto-metal albums of all time, and I honestly forgot that I was listening to it with a thimble-sized DAC amp I was enjoying it that much. The crunchy guitars on the title track snarled with all their familiar aggressiveness, and there was plenty of visceral impact from the pounding drums. There was noticeably less tonal mass compared to a full-sized desktop amp with a proper power supply, but still, it was super impressive that the GO bar could manage as well as it did. This being the case, I did engage the XBass+ mode when paired with the HD800s - it’s a more subtle EQ implementation than I’ve experienced on other iFi devices, such as the iFi audio xDSD Gryphon Portable Headphone Amp & DAC, but it certainly makes an audible difference for the better (depending on how you like your low end). 

Final thoughts

You know that little pocket on the front of your jeans? I’m not really sure what they’re supposed to be for, but I reckon you’ll definitely want to slip a GO bar in them after listening to one. The GO bar is the best-realised form of the “dongle” DAC/amp that I’ve had the chance to spend some proper listening time with, and while it’s easy to be initially skeptical with a device this size, I can wholeheartedly say that I’m thoroughly impressed. With its great DAC, IEM-focused features, plus ample power for dealing with high-impedance headphones, it’s a genuine audiophile option for all kinds of headphones if sheer portability is high on your list. While it does (necessarily) sacrifice a few features in order to arrive in a svelte little package, when it comes to listening the GO bar doesn’t ever let you feel like you’re sacrificing anything. 

I can heartily recommend the GO bar for a couple of different buyers. Firstly, it will make a terrific first DAC/amp for someone looking to get into the hobby who needs a USB DAC, and also wants the flexibility to add either IEMs or full-sized headphones into their collection down the track. The other listener who I think will appreciate the GO bar is the travelling audiophile - those of you who might have a dedicated desktop system at home, and want to enjoy great sound when you’re on the go without weighing yourself down with a larger portable DAC/amp or a DAP. 

Ifi audioPortable headphone amps and dacs