Review: iFi Audio Nano iGalvanic3.0

Introduction

My Daphile based, DIY music server continues to be weapon of choice when it comes to digital audio playback.. While I feel that it’s very competitive with some pretty pricey dedicated servers, there are some limitations due to the fact that it’s based on ordinary PC hardware as opposed to hardware specifically built for audio, particularly USB audio. The folks at iFi are certainly no strangers to USB and its problems – they’ve been hammering away at them for years, and with the subject of today’s review, I believe they’ve made a significant breakthrough. Before I get to that though, let’s talk a bit about why USB audio isn’t as simple as you might think.

The great thing about USB is that you can plug in a thumb drive, or a printer, and expect everything to work, every time. It might be tempting to think that a USB DAC would behave the same way – that it would receive digital audio in a perfect, error-free transmission just as your thumb drive receives your Word document. Unfortunately, that’s not how it works.

USB 101

USB has four operating modes: control, interrupt, bulk, and isochronous. Control is used for identification, and is how your computer is able to talk to something like a digital camera that it has never seen before, and acquire a driver for it. Interrupt is used for things like keyboards and mice. Bulk transfer mode is for things like thumb drives and printers, while isochronous is used for audio streaming.

The reason why your Word document always makes it onto your thumb drive is because bulk mode has error correction with re-transmission. If some of the bits from your document don’t make it the first time, they are re-sent. Isochronous mode has error detection, but there is no correction or re-transmission. When data doesn’t make it, you hear it as a click or a drop out, but this is still only scratching the surface. To get to the core of the issue of why USB needs so much assistance to produce good sounding audio, we need to go a bit deeper.

USB audio sound quality depends on two main factors: data signal timing and integrity, and power quality. Early USB DACs made no real attempt to address either factor, which is why they sounded so terrible. Asynchronous mode USB receiver chips made significant strides forward in dealing with the data timing issue by shifting control of when data arrives to the DAC, while first generation USB power products like iFi’s original iUSB started to deal with the problem of noisy computer USB ports, but there were still plenty of hurdles to overcome.

“Second gen” USB cleanup devices like the Schiit Wyrd, UpTone Regen, and iFi’s iPurifier series started to combine passive or active clean USB power delivery with hardware data signal re-clocking to lighten the load on a DAC’s USB receiver chip, further improving USB audio compared to first gen products that dealt with power alone. For a time, I was able to get the best results from my Daphile box by combining an UpTone Regen with iFi’s USB iPurifier 2. These two together were a considerable step up in sound both when used with my prior Lindemann 24/192 USB DAC, and my current Simaudio Moon 380D DAC, but they still left one area unaddressed – ground contamination.

Get on the ground

A USB cable contains positive and negative data lines, positive and negative power lines, and a ground line. In order for USB to work, the ground connection between devices must be present, but this does not mean it can’t be isolated so that only the core ground signal makes it through, whereas ground loops, stray currents, etc are eliminated. This is called “galvanic isolation,” and it’s where iFi’s new nano series iGalvanic3.0 comes in.

Galvanic isolation for USB has existed for awhile prior to the introduction of the iGalvanic3.0, but these devices were limited to slow speed USB 2.0 only, and they made USB data timing issues worse, not better. The iGalvanic3.0 on the other hand builds on all of iFi’s earlier progress with USB – data signal reclocking, clean power delivery (passive in this case) and adds to that galvanic isolation capable of operating on USB 3.0 at a full 5Gbps.

All of this brings us to the big question – just how does iFi’s latest “third gen” isolator, the first from the company to address all USB issues in one box, compare to my current Regen/iPurifier combo? To find out, I took both of those products out of the chain, and plugged the iGalvanic3.0 directly into the back of the Simaudio using the USB A-to-B adapter that comes in the box with the UpTone Regen. I expected the difference between the iGalvanic3.0 and the Regen/iPurifier combo to be pretty subtle – the Simaudio is a $5,000 DAC with its own galvanic isolation solution after all, how much better could the iGalvanic’s system possibly be than Simaudio’s?

Since I didn’t expect a big difference in sound, I skipped past all of the usual compressed stuff and went straight to one of my best sounding albums to begin my testing, Kauan’s Sorni Nai. I pressed the play button on “kit,” and as Keanu Reeves would say, “woah.” Wait a minute. Hold the phone. Where’d all of this detail come from? Where’d all of extra width and depth to the soundstage come from? What’s going on here? After being mesmerized by how much better my system sounded than it ever had before with the iGalvanic3.0 in place, an improvement I would describe as comparable to adding sound absorption panels to the first reflection points on my walls, I took it out, and put the Regen/iPurifier combo back in. The sound was as it had been before. Still certainly quite good, but nowhere near as good as it had been with the iGalvanic3.0.

Ok, so Kauan sounded incredible, but what about a more typical average sounding recording? Switching to “Valhalla Rising” on Grand Magus’ The Hunt, those same improvements were still there. The guitars stretched out to the edges of the room, cymbal crashes seemed more distinct and defined, snare hits had more impact, and the kick drum pounded to the extent that a DR6 recording allows. Skipping ahead to “Silver Moon,” I cranked up the volume and just reveled in how good everything sounded.

Listening to “In The Eyes of Idols” from the full dynamic mix of Witherscape’s The Northern Sanctuary, it was the same story again, with the soundstage stretching to the edges of the room and beyond. In my review of Sonore’s microRendu last year, I noted that I had a brief opportunity to test my server with the Regen/iPurifier combo against the microRendu, and I thought that those two together brought my server up to at least close to the level of what the microRendu could do when connected directly to my DAC (at that time the Lindemann). I’d love to do a re-test, because with the iGalvanic3.0 in place, I wouldn’t be surprised if the two were on an even footing, at least with the Rendu powered by an iFi iPower wall-wart, which is how I tested it. If I’m lucky enough to get my hands on Sonore’s new ultraRendu, I’ll certainly let you know how that comparison shakes out.

There is also one more comparison I’d love to do, and that’s with the iGalvanic3.0’s only direct competitor currently on the market, UpTone’s new ISO Regen. The ISO Regen takes a similar approach to high-speed capable galvanic isolation, while differing in other ways, the big one being how the two devices output their Vbus power after the isolation stage. The iGalvanic3.0 uses a passive voltage regulation system, with both the incoming and outgoing power supplied by the host USB port. The ISO Regen uses the host port to power its input stage, but its output depends on an external DC power supply of some sort. This does give the iGalvanic3.0 one advantage, and that’s complete portability. You could use the iGalvanic3.0 with a laptop and a USB powered DAC with no AC outlet at all, which isn’t possible with the ISO Regen. The iGalvanic3.0 also means that you don’t have to worry about the quality of the DC power supply, or spend several hundred dollars on a linear power supply to get the best out of it.

This is the end

I had assumed that the Regen/iPurifier combo had taken my humble Daphile server about as far as it could go, and the iGalvanic3.0 proves just how wrong I was. While it is considerably more expensive than most “second gen” USB cleaning products that do data and power scrubbing alone with no galvanic isolation, the improvement that it brings over these products is more than commensurate with the added cost. The iGalvanic3.0 is simply in a different league with anything that’s come before it, and even chaining multiple products together like the original Regen and iFi’s own iPurifier2 could not bring them anywhere near the same level of performance.

If you are using a computer as your digital music source, this is simply a must listen product. Forget everything else, try this first. I’m putting my own money where my mouth is and buying the review sample; there’s no way I can go back after having this in the system. iFi changed the game on this one, and it definitely deserves our coveted medal of honor.