By the way, you also get a USB-C to USB-A adapter for additional flexibility. There’s also a leather travel case included in the box to protect your DAC/Amp. The case also has room to hold a connection cable. Sound GO Bar delivers circa 1W onto a 55Ω load (always talking about the Balanced Ended output), which is definitely a huge lot for a dongle, and why it drives the likes of Shure SRH1540 wonderfully well, and SRH1840 near perfectly, too. Using the same measurement system, the idle current is the same as the old SMSL iDEA dongle (higher than the AQ Dragonflies), and about double the current at maximum output into a low-impedance load. The difference of course is that the iFi can do >2Vrms into 20Ω without clipping (I think the distortion is <0.1% right at 2Vrms). Lastly, GO Bar’s additional features (selectable reconstruction filters, high gain option, MQA decoding, Xbass, Xspace) are totally alien to Groove. when an MQA stream is being received : green for MQA, blue for MQA Studio and magenta for “MQB” (Original Sample Rate).

Consistently to this, GO Bar drives the likes of Final A3000, Tanchjim Darling, and even Final E5000 waaaay better then most other dongles, but does not have enough power for RHA CL2, nor of course any demanding planar overear. Host Volume Sync is off by default. To turn it on one needs to keep the multifunction button pressed >5 seconds. The switch on is confirmed by an animation played on the upper 6 LEDs on the bottom faceplate. Same procedure to turn it off : keep button pressed >5 seconds, and a (different) animation gets played on the LEDs to confirm. Firstly, next to the IEMatch switch on GO Bar we don’t find the usual “Ultra” / “High” engravings, but rather “3.5” and “4.4”. The GO Bar manual quite smokily says that “iEMatch reduces the output level, so that even the most sensitive In-Ear-Monitors (IEMs) can be matched to the GO bar”. Which is only a part of what a full-blown IEMatch does. And does not offer precise figures in terms of attenuations nor output impedances to help the user anticipate what he will get by plugging IEMs of specific impedance or sensitivity. In the end, there was no free lunch - just gratefulness to be immersed in some unique sound for a few hours. Hopefully highlighting some deltas is all I can try here. I know for myself, Goldfinger had me reaching for the next song on play (and having been gone a week as I first wrote this, was a sound I would miss): Moving over to the IE Match switch, it has three settings. First is “Off,” which sets the standard gain for both outputs. Then, by moving the button either left or right, you can select a lower gain setting for either the 3.5mm or 4.4mm output. The lower gain settings are meant for high-sensitivity IEMs and the like.

TL;DR

I only used the Moondrop Kato DD IEM for impressions from an iPhone 13. I didn't use any other IEM or any other sources. 3.5mm output only. To celebrate its 10th anniversary, iFi created an eye-catching special edition of the GO bar. Limited to 1000 pieces, the Anniversary Edition - or ‘GOld bar’ – replaces the standard version’s alloy enclosure with a copper chassis, further enhancing build quality and shielding, and smothers it in an 18ct gold plate. Power supply filtering is also further enhanced, ensuring the Anniversary Edition is truly the ‘gold standard’ among ultra-portable USB DAC amps. Truth be told, as most if not all high impedance cans are equipped with dynamic drivers, I’m not sure to understand what the purpose of a 7V+ swing really is (“stunning” spec sheet figure apart, I mean…). I'm not an IEM guy, so I basically ran through the headphone stands against all four units at least for a few minutes before settling into evaluation mode. Obviously throwing every headphone I had into a detailed accounting would have taken way longer than my allotment, but all four units seemed to manage everything I threw at them: HD280, HD558, HD650, HE5XX, OG Clear, even Atrium. Eventually I landed on the HD280 (v2016) for testing, as it's probably the most flat headphone in my kit right now.

Not only does it resemble many of its larger siblings, but it also provides much of the same functionality, like an actual balanced output (4.4mm), a Single-ended output (3.5mm), IE Match gain control and native DSD processing. It wasn't a straight up double-blind A/B-switch test setup, but spread out across the table for a few hours, this was overall a fun experiment and I enjoyed the time spent. It was also interesting to take notes on the items BEFORE seeing price or specs -- the inherent biases that I know I have get taken out of play. On the bottom of the Go Bar is the format/sample rate LED indication, a row of LED lights that give you an easy-to-understand view of the type of file being processed. Below the sample rate LEDs are additional lights indicating the effect/filters in use. Sometimes, mostly when comparing new products side by side, using it as just a DAC into a separate amp, or using it as a preamp into speakers. Hidizs S9 Pro

The Wrap Up

Thanks for the comment. Hmmm... Wondering what the measurement equipment was for that graph and what signal level was being played? Is there a post referencing the graph about test conditions?

As you can see, the iEMatch feature turned down the gain by -6dB to accommodate sensitive IEMs and might increase the output impedance (presumably this is done through a voltage divider as per this ASR discussion, effectively reducing the efficiency of the amp). And the XBass+ feature basically gives a boost in the bass starting around 200Hz and up to +7dB at 20Hz; potentially a pleasant EQ for many headphones. Otherwise the DAC/amp has a nice and flat frequency response. While you can drive pretty much any headphone with the standard gain, the “Turbo” mode is suitable for additional headroom on the most power-hungry headphones. I only had one headphone that needed it, and that was the Dan Clark Aeon Flow Closed. I do like how simple this device is AND the fact it remembers your last volume (something the other three don’t do). I also love the simplicity of this device. Mostly volume and a Mode button to change gain from low to high, change from OS to NOS, and change the screen timeout settings. GO Bar also has a +6dB High Gain mode. Unlike what happens e.g. on the GO Blu where gain selection follows an automatic system, on GO Bar it’s the user who has to manually set the device on High or Low Gain mode.

iFi Go Bar

Externals​GO Bar’s housing shape recalls that of their Nano / Micro iDSD line – just many times smaller. Within the “dongle” category, GO Bar falls more or less midway in terms of dimensions and weight: 65x22x13mm and most of all 28.5g are not certainly huge yet not entirely disregardable either when I have GO Bar connected to my transport. It’s more than twice the size and weight than an E1DA 9038S, yet much smaller and lighter compared to a Groove. At the end of the day I guess its single relevant downside is the price – which is not low at all. A few other downsides are also there, but none of those seriously shadows its positives. Turbo Mode increases the gain by 6dB. To switch this on or off, press the + and – volume buttons together for ≥ 2s. Turbo Mode on is indicated by 2 white LEDs increasing to 6 lighting up at the same time for 2s. Normal gain is indicated by 6 white LEDs diminishing to 2 lighting up for 2s. Also included is iFi’s “IEMatch” technology for use with sensitive IEM’s. This is a very handy option if you are experiencing a bit hiss with your easy to drive IEMs. I ended up not needing it personally (my IEMs are not sensitive at all,) but it is there should you have a sensitive pair. Such “guess” is also corroborated looking at the Single Ended output figures: there, the lower output impedance option does not feature a much higher attenuation as it usually is the case on IEMatch devices, but rather a slightly lower one, with a phase flip involved.