iFi Audio Micro iDac / iUSBPower REVIEW

Micro iDac USB Digital To Analogue Converter $449

Micro iUSB Power PSU $299

5 Stars

AMR unleashes budget computer audio heaven with iFi Audio’s new USB Dac and matching PSU

I BECAME INTERESTED in computer audio almost by accident. Before my seafaring career, I was content with my old (and cheap) 2.1 Altec Lansing speaker setup – it’s just a bit of background music while writing or surfing the net, after all.
The problem was that I was spending more and more time at the computer, and the relatively lo-fi sound began to bug me. That’s when I forked out on a little Topping TP30 Class-D amplifier with built-in DAC, and ditched the Altec Lansing’s for a pair of unloved JVC single driver miniature speakers (big spender, eh?)
At that stage I had what I considered a decent little desktop audio system, and although it did sound pretty good, I had officially caught the computer hi-fi bug.
Exacerbating this malaise was my recent career change – spending weeks working out at sea without a decent audio system just wasn’t an option for me, so I soon invested in a Macbook Air, Audirvana Plus, the original HRT Music Streamer and a pair of dinky-di Audioengine A2 active speakers, and duly set back out to sea.
And boy, did this setup sound good, considering the environment. So good in fact that I soon upgraded the DAC to HRT’s Music Streamer 2+ which enabled me to experience my hi-res 24/96 recordings in all their glory.

Fast forward a few months and Chris Hawkins of Feedback Audio contacted me with the details of an all-new range of affordable audio electronics from iFi Audio. I hadn’t heard of the company before, but they sounded promising. ‘Trickle down’ technology from Abbingdon Music Research (AMR) featured heavily in iFi’s product portfolio – the iDac USB D/A converter utilises the renowned ESS Sabre chipset and AMR’s jitter reducing technology, while its partnering iUSBPower psu has been engineered with ultra-low noise levels in mind -in fact, iFi’s claim of ‘9v battery’-like performance for the psu got me really worked up about the giant killing potential of these diminutive components. Chris promptly couriered the iDac/iUSBPower, the iCAN headphone amplifier and the well-specified iPhono phone preamplifier, and it was time to get down to business – starting firstly with the Dac/psu combo. Packaging for both components (in fact, all components share the same size boxes) was exceptional, with an almost Apple-like quality and feel. iFi haven’t scrimped on protection for its products, the cardboard used is extremely sturdy and could probably withstand the weight of a person standing on it (no, I didn’t try this). Both components use identical extruded aluminium casework and quality here is also top class (especially considering the price of each piece), making my HRT Music Streamer 2+ look a touch home made by comparison. Although not specifically designed for Apple computers, the psu and DAC looked like they were made for my Macbook Air and Mac Mini in terms of aesthetic and colour. Impressive.

The iDac
A simple box, the iDac carries all its technology on the inside – a single Asynchronous USB input allows bit-perfect transmission of data into the Sabre Hyperstream DAC chip where it is then re-clocked for minimum jitter and maximum resolution. No less than six internal power supplies are incorporated within the casework to minimise noise and crosstalk, while the output stage uses as few analogue components as possible. Thorsten Loesch, Director of Technology at AMR, kindly emailed me this explanation: “We actually directly use the DAC output without adding unnecessary analogue circuitry. There is simply a first order LPF with very high quality components and then the RCA jacks. Any added buffering of analogue circuitry we found to detract from the sound quality the DAC is capable of.”
iFi also uses what they term ‘Direct Drive’ technology to drive the iDac’s built-in headphone amplifier – essentially avoiding the requirement for coupling capacitors in the output stage. With a beefy 150mw output, there won’t be many headphones the iDac won’t power. Oh and yes, the iDac has a handy volume control for its headphone stage on the front fascia. They’ve really thought of everything!

The iUSBPower
What I noticed when unpacking the iUSBPower was the provision of two USB A sockets on one front panel. One is marked ‘Power’ and the other ‘Power and Audio’. iFi are about to launch a two-headed USB cable specifically designed for audio use – I’m not sure whether using this cable type would automatically stop any power transmission via the ‘Power and Audio’ socket, but if it does (the cable would need to have completely separate power conductors from the audio ones) this could have a significant impact in terms of noise rejection. Sadly, I didn’t have a two- headed cable to try out but regardless, the sonic results were impressive using a standard cable.
The other end of the psu has a USB ‘B’ connector (from the computer) and a socket for the high quality switch-mode wall wart.

Set-up
Connections were made to my Macbook Air using Nordost’s new Blue Heaven USB cable and my bog-standard cable that came with one of my many bits of computer audio gear. This is also blue in colour, yet quite possibly not to the same standard as the Nordost in sonic terms. Suffice to say it worked flawlessly, but the cable fanatic in me wonders what results would have emanated if I’d had two Blue Heavens. Maybe I’ll find that out one day soon when my bank balance recovers from Christmas spending.
Once the connections were made it was an easy setup computer-wise. The Macbook immediately ‘found’ the iDac, although I had to select it as my output device under ‘Sound’ in System Preferences. I then had to go into Audio MIDI Setup in my application utilities folder (Applications/Utilities/Audio MIDI Setup) and select ‘AMR USB Audio 2.0’. I then lovingly selected the sampling rate (192000.00 Hz) and Bitrate (2ch-24bit Integer). That was basically it, although my next step was to setup Audirvana Plus in order to have it recognise the iDac. Easy peasy, huh?
Under Audio System in Audirvana Preferences I selected AMR USB Audio 2.0 as the active audio device, and the sample rate conversion type in Audio Filters. Still in Audirvana preferences I selected SysOptimizer from the drop-down menu and ticked every box (Audirvana turns off stuff it doesn’t think will be good for sound quality). Finally, I chose iTunes from the menu and once again, selected every option – why let iTunes wreak havoc with sound quality? Audirvana also allows the creation of playlists that avoid using iTunes altogether, and that’s just what I did when playing my high-res FLAC files for part of the review.
So, that was it – I was ready to roll with the iFi iDac/iUSBPower combo. In some ways setting up a computer Dac is the modern equivalent of setting up a turntable, adjusting the VTA, anti-skate and levelling, cartridge overhang and so on. This however, is completely software based, but still pretty absorbing. All that was missing was the crackling of the stylus into the lead-in groove (actually, that was there on some of my ripped vinyl). All that was then left to do was listen to the music.

Listening
I chose my second system for this review, maybe smaller in scale than the main system I have in my lounge (Voigts/Audiolabs, etc) but it is no less involving. The system consists of my Macbook Air 1.8ghz/4gb ram (aka the source), Antique Sound Labs WAV 8 mono power amps (8wpc push-pull) and DT1 passive-preamplifier, and my sweet little Omega Super 3 XRS single driver Hemp-Cone loudspeakers. At a generous 94dB efficiency the Omegas can be driven by amplifiers with a paltry 2 watts per channel, so the extra 6 watts generated by the ASL’s would really get things rocking along, I thought to myself. Cabling was via Nordost Blue Heaven (interconnect) and Superflatline mk2 speaker cable. An interesting blend of high technology and flat earth: what the hell was it going to sound like?
Um, it was good – no, let me clarify that. The sound quality was now simply outstanding from this relatively inexpensive audio system. Comparing the iDac without using the iUSBPower and my Music Streamer 2+ saw the gleaming iDac best it in terms of imaging and detail, while the HRT was the equal in terms of dynamics and bass resolution. Connecting the psu saw the gap widen in all areas of sound quality – the bottom end seemed to reach lower and crescendos seemed more impactful and startling, while soundstaging and the ability of the system to create an image of performers on a stage seemed more realistic and palpable.
Rebecca Pidgeon’s The Raven (24/88.2khz flac) is a touch MOR, but it’s a good test of female vocals and close-miked instrumentation. Opening track ‘Kalerka’ saw Rebecca’s ‘little girl’ vocal right smack in the middle of the soundstage, while the piano, strummed guitar and strings just trotted along in the background, allowing Rebecca to do her thing with her voice. Skipping along to ‘Grandmother’, and her faux Rickie Lee Jones performance spotlighted the iFi’s sheer lack of noise or glare – music, just manifested in the room with exceptional clarity and realism.

Up-tempo stuff such as Faith No More’s ‘Be Aggressive’ off their Angel Dust album (24/96khz FLAC) displayed real drive and crunching impact. The kick-drum in particular dug deep, fully exploring the tight bottom end of the Omegas (oo-er). The snare and tom-tom drums had that ‘stick on skin’ realism, while the electric guitars soared over all the other instruments. In other words, they had excellent ‘Kerrang’!

Turning to jazz music after the headbanging session and I carefully selected John Coltrane’s sublime Blue Train (24/192khz FLAC). The title track sees John in syncopation with trumpet and trombone at the beginning of the song before he cuts loose with an extended solo. The iDac/iUSBPower combination delved deeper into this song than I had previously heard via my Streamer 2+. The resulting sound was brassier and (once again) better in terms of dynamics and detail. Both drummer and bass player were also better defined, and micro dynamics (such as snare paradiddles and sweeps of the stick on the ride cymbal) also appeared with greater clarity than I had previously experienced. And all this with a wider soundstage and increased ‘air’ throughout the recording. To put it in a nutshell, the iFi electronics took me further into the performance with a sonic delivery that belied its very reasonable price tag.

Of course, I flogged the iFi combination to death over the weeks I had it – 24/96 HD files of Bootsy, Elton, Miles and Mingus in high rotation, while plain old red-book files from artists as diverse as Tori Amos, Flying Lotus, Kraftwerk and Isaac Hayes all benefitted from the iDac and iUSBPower.

Conclusion
Purchased on its own the iDac is a killer piece of computer audio gear. It’s resolving abilities were a notch above my highly regarded Music Streamer 2+, and although a match for the iDac in bass response and dynamics, in just about every other facet of sound quality it was bested by the luxurious little iDac. Add the iUSBPower and it really soars above the 2+ in terms of performance with stunning sound. Now the iUSBPower can be purchased on its own to supply refined juice to Dacs other than iFi’s (I used it on my HRT and heard an improvement in sq.) and can even clean up the power supply between an external hard drive and computer, but I’d definitely purchase both together based on my listening sessions – the sound quality is so good you’d be mad not to.

Available online directly from Chris at Feedback Audio, the iFi iDac and iUSBPower are simply outstanding and one of the bargains of the year. GARY PEARCE

www.feedbackaudio.co.nz

TAGS: , , ,