Review: iFi Audio Micro iPhono and iDSD
During last summer I was given the opportunity to bring the iFi nano DSD on vacation with me. Despite the moderate size this little DAC-headphone amplifier managed not only to put a smile in my face but to literally make me cerebrate for weeks on what is possible in terms of audio playback nowadays for less than $200.
It got me thinking of my first hi-fi rig, the upgrades that it went through, from one amplifier to another trying to find the “right one”, then the first decent turntable and cartridge, and so on. Of all the equipment from back-then, I’ve held on to only the turntable, a Goldring GR2, which was nothing more than a rebadged Rega. It was preferred over the original as it came fitted with what I considered to be a much better cartridge, the Goldring 1012GX. The main problem was that the vast majority of entry-level amplifiers, the ones I could afford as a student leaving abroad, only handled moving magnet cartridges. The word ‘handle’ is more of an euphemism; many of those phono stages were enormously lacking in detail retrieval and dynamics, making vinyl sound as bad as it gets. The only integrated amplifier with a decent phono input was the NAD 3020, but still, low output MC cartridges were out of the question. As for digital audio, that was the zenith of the red book era, with external DACs being pure science-fiction for most students.
Audio is quite different as we speak. Digital made more than a few steps — it took a giant leap forward with high-resolution — while the limit of what is possible in analog playback got pushed beyond the imaginable with highly refined MC cartridges, perfect geometry tonearms and amazing turntables. Much of this applies only to those who care to spend a small fortune, of course, but what about the offerings for the budget oriented? What would it take to put together a quality system without breaking the bank today?
Look no further
iFi Audio has you covered in all imaginable ways with the “Micro” line. The mid-priced series of electronics from Abbingdon Music Research‘s “affordable” subsidiary includes a USB to SPDIF converter, tube buffer, headphone amplifier, an external USB power supply — and of course the phono stage and DSD DAC reviewed here. All of these come with the same silver casework, and if you end up buying more than one unit, iFi offers a mini rack that can accommodate them in what could become a perfect desk companion.
All iFi Audio products come packed in an iPhone-ish white box that contains basic cables, silicone footers and a switching mode “ultra-low noise” power supply. Build-quality is very good; they feel rather solid in-hand and seem sturdy. Passive components are high-quality surface-mounted ones such as tantalum oxide resistors, TDK high stability capacitors, Panasonic PolyPhenylene Sulfide capacitors and so on. Units in the Micro line measure approximately 18x7x3 cm which places them somewhere in between desktop and portable category.
David vs Goliath: iPhono vs ASR
Basic ingredients for your analog rig are a turntable with tonearm, a cartridge and a phono amplifier; you can spice up the result with various cables. As far as turntables go, the obvious entry-level suggestions are Rega, ProJect or Music Hall. At $400, give or take, all these entry-level models will perform marvels. Think that $400 is still pricey? Check U-Turn, at $200, is not a bad idea for starters. Despite a tendency to look rather flimsy at first sight, these ‘tables will last longer than you expect. My rebadged Rega still works just like when it came out of the box back in 2000.
Many of these spinners will come equipped with a cartridge, usually an entry-level moving-magnet design from Ortofon or Audio Technica. You might think that upgrading this little bit at the end of the tonearm is priority number one, but experience got me thinking otherwise. After many years of analog playback, I ended up believing that the phono stage is the undisputed game changer. My current phono, the ASR basis exclusive, is big, shiny, weighs a slick 80 pounds (including the PSU), and costs way more than my first entire system (… and the second and the third combined ….). I have hooked it up with many beautiful (translation: “expensive”) cartridges over the years, but I also tried it with entry-level ones, some of which I still retain in my collection.
I have also experimented with the opposite, that is, expensive cartridges paired with cheap phono stages. A well-designed phono amplifier will squeeze out every last drop of performance from your cartridge, especially those that have many settings for gain, capacitance and resistive loading. Things just don’t work the other way around. No matter how good the cartridge is, if you cannot match it electrically to the phono stage, or if the phono stage’s amplifying section lacks transparency, it will get you nowhere close to analog bliss.
The iPhono is the undisputed champion of configuration flexibility, and not only for the $399 price. Gain is adjustable between 40 and 66dB, with the later being more than enough for my ZYX 1000 Airy 3-X (low-output version). At this price range, you will be hard pressed to find another phono stage capable of handling 0.24mV of output. Resistive loading is adjustable between 22Ω and 1kΩ for moving coil carts, with the selection being made with silver-plated Alps dip switches. For those moving magnet cartridges that require higher capacitance, one can add up to 400pF for a total of 500pF, which is what I did when I played my favorite vintage MM transducer, the highly acclaimed Shure V 15 III, and this provided the best possible high-frequency extension, while maintaining a more-than-vigorous bottom-octave on Van Der Graaf Generator prog rock classic “Cats Eye/Yellow Fever“ (The Quiet Zone/ The Pleasure Dome, Charisma Records). The typical flimsy sound coming from an entry-level phono stage? Nope. Faithful timbre too? Yup.
The iPhono also offers nothing less than six equalization curves, including those widely spread before the introduction of RIAA, such as DECCA and Columbia. This option will probably go unused by most potential buyers, but I gave it a test with the Denon DL 102 high output mono MC cartridge and some of my favorite recordings from the 1950’s like Fats Waller on La Voix De Son Maitre (FFLP 1010) or Beethoven’s Fifth symphony with Klemperer on Columbia (33C1051). These pre-RIAA curves impart a slight tonal drift to the end result, but unless your system is truly top-notch, you could easily live without them. Consider the EQ selection as the cherry on top of the cake. The iPhono not only stood very well but provided a blast from the past, the sweet Class-A output stages offered a full immersion in the world of vintage recordings.
Note that my reference, the ASR Basis Exclusive, offers nothing more than standard RIAA de-emphasis and just one additional capacitance option. Yes, the sound is clearly better in every possible aspect and especially in terms of channel separation, imaging and fine detail retrieval, but also please consider the enormous difference in price; this kind of separation is to be
demanded expected. To be honest, I have had awful experiences in the past with entry-level phono stages, such as the Project Phono Box, or those embedded in low-end integrated amplifiers — which on paper at least appeared able to deliver enough gain for even LOMCs, but then fail to deliver anything close to an acceptable sound. No wonder why so many people in their first steps in hi-fi choose digital audio over analog, my experience with the ProJect phono box was muffled, lifeless and boring.
Back to the iPhono. In real life, David never really even marks Goliath. When Goliath is a German behemoth of a phono stage like the ASR, same goes. That said, the iFi iPhono is clearly a significant upgrade for audiophiles either starting out on their vinyl crusade or those of us working within a budget.
Present and future: iDSD DAC/ Headphone Amplifier
Based on the Burr Brown 1793 chip (not the latest of the crop among digital to analogue converters, but interestingly one that handles PCM, and DSD in native mode), the iDSD DAC and headphone amp was launched in 2014 after a long period of crowd-based design that took place over on Head-Fi.Org. Crowd-based design, you ask? Yes — all features were discussed and put to a vote by the forum’s members while designer Thorsten Loesch and the rest of the AMR-iFi Audio team gave details about the various technical options and solutions that could be implemented on the iDSD. I challenge you to read that thread, it is enormous (there are over 2,000 posts at this point); for the rest of you, I will highlight some of the principles here for those who lost the opportunity to actively participate in the development.
The BB 1793 was chosen because it handles DSD natively, with the stream passing through nothing more than an analogue low-pass filter, while maintaining a true multi-bit architecture for PCM signals. A small multicolor LED light placed in the top-plate indicates the sampling frequency and status of the device. The USB receiver is a highly customized latest U-series asynchronous XMOS Octa(8)-Core chip, and packs a purifier similar to the standalone that iFi has on the catalog that claims to remove several dB of noise from the connection. The XMOS modules receive their “pace” from an ultra-low jitter master clock in a scheme that iFi calls “Star-Clock” which allegedly lowers significantly the overall jitter performance.
Externally, the iDSD has knobs, buttons and levers all over the place; it is highly adjustable, just like the Micro iPhono. You can choose between a direct output with fixed gain, or use it as a preamplifier through the 3.5mm jack input and control the volume through the knob on the front. Another button will adjust sensitivity for your favorite in ear monitors. Two small levers turn on the X-Bass and the 3D Holographic features that create the illusion of a wider soundstage and pump up the bottom octave for those who crave the sensation of a sub-woofer attached to their ears (or for their two-channel playback system, as these modifiers work with the RCA outputs, too).
There are also three digital filters to choose from; Standard, Bit Perfect and Minimum Phase. Most of my listening sessions tasted plain vanilla, meaning that I opted for the Bit Perfect filter, and without the use of 3D or X-Bass.
The capabilities of this Swiss Army knife of a device do not end here. The SPDIF input works like an output too, so you can use the iDSD as an interface or S/PDIF converter for other digital sources. Not enough? The S/PDIF is a hybrid, and will take optical-in, too. Want even more? How about the possibility to use the iDSD to charge your cell phone? Yes, it can breathe new life into your smartphone from the internal 4800mAH battery through the side USB port.
The battery is here to provide clean power for the delicate audio circuits, but if you end up depleting it, the iDSD will also work with the power coming from a standard computer USB connection. It will provide several hours of portability even with highly demanding headphones.
During the development, Head-Fi’s members requested that the Micro iDSD was 75% desktop and 25% portable. iFi Audio already has a 100% portable solution, the Nano, which, while it remains a fun piece of equipment, will not sit as comfortably on your main rig as the Micro iDSD. At $189, we might be asking a bit much, so let me tell you a bit more about the sound qualities of the $499 bigger brother.
Overall character is what I would describe as “melodic”, with a credible timbre for voices and acoustic instruments like on Yasmin Levy’s latest live recording album Tango (16/44.1 FLAC). The Israeli singer is an ambassador of Ladino music and her live performances are passionate like few, she has a fire burning. Despite a slight lack of air, the iDSD created an emotional involvement by highlighting her deep, sensual voice while placing the accompanying guitar deeper in the stage. Cellos blended well with bandoneons without being overly fuzzy, while soundstage was wide enough to resemble a live recording.
Moving to Aerosmith’s classic ballad “Dream On” (remastered 24/96 FLAC), the iDSD presented Tyler’s voice perfectly centered between Perry’s and Whitford’s guitars, with bass drum and bass on the sides and crush cymbals on top. Imaging is rather good. On the other tracks of the homonymous album, the iDSD (again) sounded quite melodic, maybe a bit warmer than what you would expect from a 70’s rock band.
If you have a stereotypical idea of how the latest generation ΔΣ DAC sounds, then start thinking the opposite. During the same period I was auditioning the Audiobyte Black Dragon DAC which at $2,100 sports a FPGA receiver with femtoclock, two of Asahi Kasei’s 4396 24 bit decoding chips in true balanced operation and fully discrete class A output. With the Black Dragon sitting on the antipodes of digital reproduction, comparisons were easy to make. In fact the Romanian-made DAC offered more detail, microdynamics and depth in the soundstage. What it did not do was to hide some nasty passages in the upper mids and high frequencies, the ones many ΔΣ DACS represent in overly analytical fashion and make certain rock recordings end up in listening fatigue.
And there is more: the iDSD is also a capable headphone amplifier, but thinking of it “capable” is not enough to describe it. The output power is adjustable ranging from 500mW/8Ω in “eco mode” all the way to 4000mW/16Ω in the “turbo mode”. Continuous power output is specified at one entire Watt@64Ω, which translates into driving capabilities that will put to shame many of the standalone headphone amplifiers currently in the market, and guarantee a huge dynamic range. With maybe the sole exception of the HiFiman HE-6, it will drive comfortably just about everything including my favorite planars, the Audeze LCD-X. With these on my head, George Ezra, the boy with a grown man’s voice singing the blues in Brit style, was astonishing good, his darkish bass voice and moody tunes played on electroacoustic guitar make an exceptional debut album and the iFi is spot on, delivering warmth without widely trespassing into mellow. “Did you hear the rain” will become a future classic.
Happily, iFi engineers know that many prefer in-ear monitors instead of classic headphones, and they have provided the possibility to adjust the output impedance. This is definitely not a common feature and blends well with the 25% portability and both iPhone ad Android phone compatibility that many customers wanted for the iDSD. Giving it a try with my Sony MH1 IEM was more than good, the detailed character of those neodymium magnets matched exceptionally well with the iDSD headphone amplifier. If it wasn’t for the weight and size (you need a backpack to carry it around), I would easily pick it over the LH Labs Geek Out 1000, which offers a bit more detail but has an intrinsic metallic character in the upper mids.
Entry level system that does not sound like one
Going back to the virtual system I would build with today’s equipment, we still need to discuss amplification and speakers. Scot had a very interesting piece here on Part Time Audiophile about affordable speakers and some entry-level amplification, do give it a read!
As for an entry-level pair of headphones, the AKG 7xx that went on sale recently on Massdrop, or maybe the classic AKG 240, should (with their highly-detailed sonic signature) pair very well with the warm character of the iFi headphone amplifier. Staying under the $200 mark, Sennheiser’s HD 558 would also be a nice option.
With the iFi Micro series, you pay for second-from-the-last-row tickets (almost as cheap as it gets), but then you find yourself sitting half-way to the ring. Not every single detail is happening right in front of you, but you are there, seeing the action, and absurdly close to those who spent several times more. Both products are as future proof as it gets. Not only they cover all bases with a series of adjustments that even much more expensive electronics cannot match, they also sound musical and involving.
What more could you ask for?
Type: MM and MC solid-state phonostage
- Frequency Response: 10 Hz to 100 kHz (0.5dB)
- Dynamic Range(MM): >96dB
- Dynamic Range (MC): >90dB
- Signal to Noise Ratio (MM): >76dB
- Signal to Noise Ratio (MC): >82dB
- Total Harmonic Distortion: <0.01%
- Output Impedance (Zout):
- Input Voltage: AC 100 – 240V, 50/60Hz
- Power Consumption: < 4W
- Dimensions: 158 x68 x 28 (LxWxH in mm)
- Weight: 0.44 lbs
iDSD DAC-Headphone amplifier
Type: Battery powered DAC with headphone amplifier
- USB 2.0 Type-A OTG socket (with iPurifier technology built-in)
- Compatible with computers (Apple/Win/Linux), iPhone, iPod Touch, iPad and Android Devices, camera kit or USB-OTG cable required (full USB 3.0 port compatible)
- Intelligent S/PDIF coaxial RCA three-way combo S/PDIF port
- Coaxial In/Out and TosLink optical In) for up to 24-bit/192kHz PCM
- Analog audio RCA, SmartPower Socket fast charge all portable devices. Compliant with USB battery charging standard 1.2V to 5V @ 1.5A
- HP Output: Audio 6.3mm Headphone Jack
- Volume with Power On/Off switch
- Precision analogue volume control
- 3.5mm Input Auto disable the digital section when this is in use
- X-Bass On/Off
- 3D Holographic Sound On/Off auto-switching
- 3D Holographic speakers and headphones (two separate and distinct circuits)
- Power Mode: Turbo, Normal, Eco computer controlled power and gain scaling
- Polarity: Normal or inverted
- Filters: 3 positions, 6 filters total
- Line Direct / Preamplifier function enable / disable, 0/9dB gain selectable
- Fixed 2V or variable to 5V
- iEMatch: Perfect-matching circuit for IEMs
- DAC: Dual-core DSD, DXD, PCM DAC by Burr Brown two-DAC chipset
- Chip has 4-Channel; 8-Signals, custom interleaving for maximum SNR
- Bit-Perfect DSD processing, Bit-Perfect PCM processing
- Ultra low jitter GMT computer controlled
- Femto Clock: RMS jitter 12 kHz to 1 MHz < 280 Femtoseconds
Audio Formats (all native decoding, no internal hardware conversion)
- DSD 512 / 256 / 128 / 64, 24.6 / 22.6 / 12.4 / 11.2/6.2 / 5.6 / 3.1 / 2.8
- DXD 2x / 1x at 768 / 705.6 / 384 / 352.8 kHz
- PCM 768 / 705.6 / 384 / 352.8 / 192 / 176.4 / 96 / 88.2 / 48 / 44.1 kHz
- PCM Bit-Perfect Processing/Minimum Phase/Standard Digital filters selectable
- DSD Extreme/Extended/Standard Range Analogue filters selectable
- DXD Bit-Perfect Processing Fixed analogue filter
DAC Section Specifications
- Dynamic Range (Line) >117dB (A-weighted)
- THD & N (0dBFS Line) <0.003%
- Output Voltage (Line) >2V
- Output Impedance (Zout) < 240 Ohm
- Jitter (correlated) Below AP2 test set limit
Headphone Power Output
- Turbo mode 10.0V/4,000 mW @ 16 Ohm (>1560 mW @ 64 Ohm)
- Normal mode 5.5V/1,900 mW @ 16 Ohm (>950 mW @ 32 Ohm)
- Eco mode 2.0V/500 mW @ 8 Ohm (>250 mW @ 16 Ohm)
- Dynamic Range (HP) >115dB (Eco Mode, 2V Out)
- THD &N (HP 500mW/16R) < 0.008%
- Output Voltage (HP) >10V (Turbo Mode)
- Output Impedance (Zout)
- Continuous Output Power 1,560mW @ 64 Ohm Load
- ATC SCM 40 speakers
- ASR Emitter I HD amplifier with external Akku
- ASR basis HD phono stage
- Project phono box
- Garrard 401 turntable with NSC motor controller, Kuzma Stogi tonearm with Van Den Hul 502 silver hybrid wiring, SAEC 308L tonearm with Jelco 506 cable, SME 3009 tonearm with SME cable.
- Goldring GR2 turntable with OEM Rega tonearm
- Cartridges: ZYX 1000 airy3-X low output MC, Denon 103R MC, Denon 102 mono MC, Shure V 15 III MM, Audio Technica 20Sla MM
- Audeze LCD-X headphones
- Sony MH1CBLK In Ear Headphones
- Audiobyte Black Dragon DAC – headphone amplifier
- LH Labs Geek Out 1000 DAC – headphone amplifier
- Van Damme UP-LCOFC 2x4mm2 speaker cables
- Signal Projects Monitor speaker cables
- Nordost Spellbinder IC
- Stereolab Superleggera Blue IC
- Belkin Gold USB cables
- Windows 7 64 with Foobar v1.3.2
- HTC one mini 2 with Hiby Music Player