review by Andrew Ballew
My background is in music. Yes, a bland and generic
statement, yet indeed is true. Though I have no poetic inspiration that inspires great prose to roll off my tongue like a Greek master, nonetheless, it is true that I studied Classical Music on the dollar of the University of Tennessee. (GO BIG ORANGE!) One of the things required of a 'music major' is Ear Training. What a beautiful course; I wish all college courses were the same. If one masters the material early, they achieve an 'A' and never return to that class again. In fact, one may enroll into the higher levels immediately, and before one is aware, so to speak, 2 years of credit in Ear Training appear on transcripts in a matter of months.
Yeah, I was one of those kids. I passed first semester Ear Training in a single week. I have always had the ear for the subtleties in music. One of the more basic exercises is a simple tuning test. The subject must listen to a series of pitches all within a few 'cents' of each other, and must match them exactly with no assistance. Only your ear can be your tool.
How that helps me as an audio technology critic, I am not sure. My hope however is my ear is just as attuned in this task as it was all those years ago in the Ear Training Lab. Readers can be the judge of that. But for now, let me be the judge of the subject of this entry. The iFi ZEN DAC V2.
iFi Audio, a part of AMR Audio, has offered budget but excellent sounding technology since 2012. The first product to the market was the semi-portable iDAC. It was based on ESS technology, and received very good reviews in the audio press. iFi continued to build on their early success, finding a popular niche in the portable and 'head-fi' scenes. Interest in what iFi was doing is how I became interested and involved in the 'head-fi' scene.
iFi, at that time under the technical leadership of Thorsten Loesch of DIY fame, left behind the ESS 'ready made' reference standard, in favor of the Burr-Brown/Texas Instruments DSD1793 chip, which would become the backbone of iFi tech. iFi pushed the limits and continues to push the DSD1793 beyond what its original Japanese engineers ever considered possible.
One of the more appealing aspects of the chipset is it has a separate logic that processes DSD in its native format, bypassing the onboard Delta-Sigma Modulator. Many would consider this 'pure' or 'native' DSD processing, as the DAC output 'switches' groups of resistors to act as a Moving Average FIR filter with only 8 clock cycles/bits of delay for the taps. It is an excellent choice for DSD playback, as well as PCM via its own unique process. Click here for my in depth explanation why this chip was chosen by iFi.
Internal to the ZEN DAC V2, the DSD1793 shines, although in this case it has limited features as compared to some other iFi products. In higher end iFi hardware, the chip can process Double DXD over 700khz, and DSD up to 1024fs. NOT HERE though. This ZEN V2 is limited to 1x DXD at 352.4 and 384khz, and DSD at 256fs. (click here for more info on the venerable chipset)
So how does the iFi ZEN DAC V2 stack up to its peers? After a thorough review, it acquits itself quite well.
Compared to other iFi offerings, this is quite a simple DAC to operate. Install the necessary software if you have a PC, plug in the DAC, and voila! MAC computers are simply plug-in-play, however DSD must be transmitted via DoP. Although Roon doesn't recognize the iFi ZEN DAC V2 as ROON READY, Roon spots the DAC and you can configure it as a USB device via the Roon control panel very easily. (Want true ROON READY ethernet/wifi connectivity? The iFi Stream is easily added and is the subject of an upcoming review)
Once you have decided how you will deliver sound to the DAC, it is easy pickin's. Every software I have thrown at it from Roon to Jriver and Audirvana to Foobar, comes accross without a hitch.
The ZEN DAC V2 can be used as a standalone DAC with analog volume control. In this case, there is a switch on the back that toggles the output from 'VARIABLE' to 'FIXED'. Variable mode with volume control at maximum will produce a higher voltage output than fixed mode, and can allow one to bypass any extra preamplifier in favor of a direct amplifier connection. None of my tests were conducted this way. All were conducted in fixed mode.
The front headphone output is always variable regardless of the switch on back. Also, iFi is kind enough to take any guesswork on what the gain need be via headphone output. It has a 'POWER MATCH' button on the far left of the front panel. This is a necessity for allowing compatibility with different headphones. My test reference Sennheiser HD650 were underpowered with the power match turned off. A push of the switch and all was well. No longer did volume need to be at 100 percent for average listening levels. Now I can listen at average to high levels with the volume dial around 40 to 50 percent.
Headphone outputs come in two forms. The 1/4 inch single ended headphone output, as well as a 4.4mm balanced Pentaconn output. Pentaconn output is also available on the back, allowing a short jumper cable to attach to other Pentaconn devices such as the ZEN CAN headphone amplifier. Standard RCA stereo terminations are included if you do not have a Pentaconn device, although there are several solutions that breakout standard XLR pin L/R terminations from a single Pentaconn connector. I would recommend the iFi cable, but a quick browse of Amazon shows several competent looking aftermarket solutions as well.
One final feature found on the front panel is a 'TRUEBASS' button. True to its word, it gives a noteworthy boost in bass frequencies, however, this boost is only applicable to the headphone outputs. The amount of boost offered is visible in our MEASUREMENTS SECTION, below article.
Power for the iFi ZEN DAC V2 comes from the 5v bus on the USB input. However, also supplied is an external switching supply that is said to provide better performance. I noted no measurable difference; however it is admitted that measurements only tell part of the story. The human auditory system is very complex and not completely understood. It is possible one may find a subjective listening advantage. For disclosure, all my tests were conducted using a iFi iPower 5v external switching supply.
Now came the time for some listening. The listening notes you read below come via a HP all-in-one PC running Roon. I am evaluating the DAC with its own headamp, while Sennheiser HD650 headphones are the listening transducer of choice.
I opened Roon and queued up a few of my reference tracks to see what this budget powerhouse can do. First up was the Allegro from Sibelius Violin Concerto in D minor op. 71. Performed by Akiko Suwanai in 2002 with the City of Birmingham Symphony Orchestra under the direction of Sakari Oramo, it is recorded in native DSD64 by the impeccable Polyhymnia team and is part of the Philips Classics Decca library. A good DAC can transport one into another world with this recording. It can be a transcendent experience that defies the mundane daily routine.
What strikes first is the excellent tonality. The violin sounds, well, like a violin, which is not exactly an easy task. The overtones send shivers down the spine, and there is nothing that sounds clinical here. It 'rings' and I mean ring in a good way. I call it 'ear candy', and I could get lost in this beautifully musical presentation for hours on end. It is not the most detailed presentation of this recording, yet nothing seems missing while you are in another world of musical bliss. Criticisms are small, and considering the price of this kit, more nitpicky than anything. The overall orchestral soundstage is slightly congested with tones that can sometimes be a bit wooly. The brass section on the other hand, is powerfully dynamic and beautiful. Brass comes across as powerful and low distortion, and the tight intonation of the BSO players is done no injustice. It is worth noting that the most significant harmonic distortion is even order; the 2nd harmonic octave is the largest contributor to harmonic distortion. This nature of the distortion is so important, and more telling than just a simple 'THD' number. The effect with brass sends goosebumps running down my arms. In turn, backgrounds are quite black due to the wide -114db(A) signal to noise ratio, and there is always a good sense of the recording space. We are off to a great start with this little DAC that can.
Next up on my listening chart was "Ballads for Audiophiles" performed by Aldo Zunino, Alfred Kramer, Paolo Birro, and Scott Hamilton. The album was recorded at the Hotel II Castello – Palazzo di Scoto di Semifonte in Stereo DSD64 on the Pyramix Recorder using a DCS ADC for the Fone label. I cued up the track "Everything Happens to Me". As a concert pianist, I appreciate when the recording engineer gets the piano just right, and it is very right here. The sonority and the decay is captured perfectly, and the ZEN DAC V2 does not shortchange anything. The placement of the piano in the mix is slightly behind and to the left, and once again the ZEN is powerful enough to call attention to many of the small details that can fool us into thinking we are right there in the room with the players. It makes all the difference in the listening experience. Lesser DACs can make a saxophone sound 'honky' and somewhat indistinguishable from a few other reed instruments, but here, the ZEN DAC V2 nails the tone and sonority. Many fine details are present to complete the illusion. Every breath and keypress is here, helping create the 'live' illusion. The drums present with no unnatural distortion or harshness. Cymbals have a natural tonality. The bass line is very good, but can get a bit wooly and indistinct at times. Overall, the presentation of this piece is very, very nice and quite frankly for the money, may be hard to beat.
No review is complete of this DAC without mentioning it is a full MQA decoder and renderer. The next demo I queued up was from Tidal Masters. "Blues from Before" on the album "Four" performed by Bill Frisell. WOW what a sound. I know the arguments about MQA, and it has its lovers and haters. All I know is, it sounds GREAT. I don't know why, (actually I have my reasonable suspicions) but it is just good listening! The iFi ZEN DAC V2 brings outstanding MQA playback to this entry level price bracket. Guitar is captured with outstanding tone and nuance, while drums sound realistic and live, with excellent depth and layering. The distinct 'bell like' tone of the clarinet is captured and reproduced commendably here. Things sound just 'right', and there is excellent 'space' for all instruments to 'breath' and interact.
Having heard quite a few DAC/headamps in this price range, I have yet to hear anything exceed the iFi ZEN DAC V2 for under $200. Of course I have not heard every DAC in this price range, but I am confident that if you are looking for an entry into real hi-fi and have a smaller budget, or just don't think the incremental improvements that come with higher priced kit are worth it, the ZEN DAC V2 is a DAC for you. How it might compare to the newer Signature edition I do not know. What I do know is you cannot go wrong with this excellent DAC/headphone amp. However, if your primary use is with headphones, stick with phones that are reasonably easy to drive. Some of the more power hungry cans out there will need a separate, more powerful headamp, such as the matching ZEN CAN, currently under review.
CLICK here for factory specs.
our lab measurements: (please note that graphs are at bottom of article)
Frequency response (from 20hz to 20khz), dB -0.35, +0.01
Noise level, dB (A)-114.1
THD, %0.000299 or -110.5db
SINAD, %0.000891 or 101db (-101db THD+N)
Stereo Separation, 128db@20hz, 100db@800hz, firstname.lastname@example.org, 78db@10khz
Jitter (24BIT 44KHZ), <36 picoseconds RMS
Linearity -100db, within 0.1db
Linearity -110db, within 2db
The iFi ZEN DAC V2 has right above 19 bits of resolution.
All PCM rates below 352.8 khz are oversampled with a FIR Linear Phase filter with a somewhat sharp rolloff.
**Of interest is the original ZEN DAC could receive a firmware update that enabled the iFi 'GTO' filter. The GTO filter is a very short minimum phase FIR filter with no pre and very 'minimal' post ringing, with a slow rolloff and less image rejection above Nyquist. As far as the iFi ZEN DAC V2 is concerned, I cannot find any confirming data saying it can be updated to use the GTO filter.**
The iFi ZEN DAC V2 frequency response is mostly flat with a rolloff that is down about 1.5db at 40khz (24/96 sample rate). Via headphone output, the frequency response is also quite flat, dropping off to approx. -0.75db at 20khz (24/44.1 sample rate). Stopband response above Nyquist at 24/44.1khz approaches a strong -90db.
Channel Balance is absolutely superb via both single ended RCA and balanced Pentaconn outputs. Via headphone output, Left and Right channels have a slight imbalance of less that half a decibel across entire frequency range. In practice this should not be of any notable detriment.
BASS BOOST, an analog process that preserves bit-perfect integrity of the digital signal, provides a healthy if not hefty boost to frequencies from approximate 200 hz extending downward into the infrasonic, with what appears to be about a 10db gain at 20hz.
Jitter is well controlled here. iFi/AMR has always used a buffer system and a reclocker to reduce jitter, and that process has seen considerable improvement as their products have evolved. The noise floor is very clean, free of PSU sidebands, hash, or idle tones. As expected from such a clean result, the jitter measures below 25 picoseconds.
Linearity is very good. Considering the DSD1793 chip is a legacy chip from a couple decades ago, the linearity of this chip, and as implemented in the iFi ZEN DAC V2, is very impressive. It challenges many much, much more expensive DACs in this metric. The ZEN V2 linearity/resolution is essentially perfect down to -100db. At -110db, worst case error is 2db.
The iFi ZEN DAC V2 measures well. All our tests came back close to the specifications advertised by iFi. Jitter rejection is very good here.
Highly recommended DAC/headamp at this price, and should make a few more expensive DAC/headamps sweat it out.
OUR RATING: (0-10 scale. 8 or higher numbers represent best of industry. For the final score calculation, each category is given a (undisclosed) weighting and is tallied for final score. Although perfect 'fairness' is unlikely, our system tries to be as unbiased as possible.
sound quality: 8.7
build quality: 9.0
ease of use: 9.5
TOTAL RATING: 90.5
note, you can click the pics below to enlarge in a lightbox. Mobile devices may treat this in unpredictable ways. It seems 'landscape' mode, phone or tablet turned to the side, gives best results.