ifi Zen Stream vs Bluesound Node vs Chord 2go/2yu
** I want to take this opportunity to give a shout out to my favorite salesman at TMR Audio: Mario. Not only is he knowledgeable and friendly, but he’ll often be able to discount a meaningful amount off of the MSRP (usually more for new items) if you call him. I did not pay the above prices for my units. Also, both TMR and Headphones.com have generous return policies, allowing you to easily test gear in your home. DM me for his email.
I finally scratched an itch I’ve had for a long time. After feeding my DAC for well over a year via a USB cable coming straight out of my custom-built mini-PC server/streamer, I figured there must be something to a whole segment of servers and/or streamers for which the hardware is (more or less) purpose-built for audio. For context, my mini-PC uses the same hardware and software as a Roon Nucleus - simply without Roon’s case or pre-installation of their (free) music-only operating system. Roon is super cool and actually has a dedicated knowledge base to walk you through how to build your own NUC-based streamer. The Nucleus uses an off-the-shelf computer-on-a-chip made by Intel (NUC) and a very standard power supply, neither of which are made with sensitive audio systems in mind. Was I cutting my DAC off at the knees? How much would I have to spend to do “better”?
Streamers run the gamut from this $99 WiiM Mini to this $5,700 (!) Auralic Aries G2.1 - and I’m sure you can spend less or more if you want to. I have a fairly high end system, so I wasn’t going to target the very entry level, but I mainly wanted to know how much I’d have to spend to noticeably improve over what I already have in the NUC over USB. I also didn’t want to be tethered to my router, so WiFi in, digital audio out was a top requirement. After many hours of research, I decided to try the highly popular ifi Zen Stream and Bluesound Node, while also throwing in the mix a much more expensive Chord 2go/2yu combo, because I (a) wanted see if it was worth the much higher price, and (b) I have so much Chord gear already (Mojo, Hugo 2, DAVE, M-Scaler), so I was primed to assume this would integrate nicely.
I feel compelled to include the usual caveats: my system is not yours, my power grid is not yours, my music preferences are not yours, and my ears are not yours, so it’s absolutely possible for you to have a different experience. Still, I hope this will be a useful data point for folks grappling with this product segment.
The streamers definitely sound different. More importantly, the coax/bnc/usb outputs even on the same streamer often sounded very different. Of course, the more sensitive your system is the more this matters, but the gap between the best output and the worst was wide enough that I would straight up recommend someone with a moderately resolving system to not use the worst. You’ll also have to excuse my use of “better” and “worse”. Unlike DACs, amps, and even cables, these streamers shouldn’t be imparting a “flavor” that is to your audio taste. They’re supposed to hand your DAC the correct 1’s and 0’s, clocked as accurately as possible (yes, many DACs reclock, but still), while not also injecting noise (RF or otherwise) into your system. The most apparent differences I heard were (1) blackness of background / degree of digital glare, and (2) crispness of transients (i.e. the punchy part of a note, like a drum hit or pick on a guitar string) and audio image. In fact, this exercise was the best demonstration of “digital glare” I’ve ever heard. Blacker background / less digital glare is better. Nobody wants more. Crisper transients and image are better. If you want a relaxed tone, buy a DAC/amp/cables that accommodate that, but don’t hurt the integrity of what you start with. So, “better” and “worse”. Interestingly, no single output sounded best at both (i.e. blackest background and crispest transients/image), so it seems there may either (1) be engineering tradeoffs between the two, or (2) be psychoacoustic perception nuances at play in terms of how transients are perceived with a blacker vs grayer background - but I cannot be absolutely certain.
Results First. Details Later.
- ifi Zen Stream coax: A (Blackest background, but transients not quite as tight as Chord)
- Chord 2go/2yu coax: A (Tightest transients by a hair, but background not as black as ifi)
- Bluesound Node coax: A- (Transients closest to ifi and blackness of background closest to Chord, so ties 2nd best in each. Still very good.)
- Chord 2go/2yu USB: B+ (Clearly the best USB background and transient sharpness)
- NUC Streamer USB: B (Similar background to Chord USB, but transients a hair less tight)
- Bluesound Node USB: C (Some digital glare. Slightly smoothed over. It’s okay, but not ideal.)
ifi Zen Stream USB: D (Pretty bad digital glare. Smoothed over. Don’t use ifi USB.)
ifi Zen Stream Summary & Commentary
.+ Blackest background over digital coax, resulting in exceptional detail presentation and instrument separation
.+ Fantastic form factor
.+ Setup easy as pie
.+ Rock solid wifi connection, and allows 2.4G and 5G
.+ Price! $400 is a steal for this quality (out of digital coax, anyway)
.- USB output is very poor, sounding smoothed over and highest noise floor
.- No BNC output
.- DSD256 not supported via DoP and the conversion sounds pretty bad. DSD64 is great over DoP. Not sure about DSD128.
I had high hopes for the ifi Zen Stream when I ordered it, and boy was I disappointed when I started my testing using the USB cable. To confirm my initial listening perceptions, I gave my non-audiophile wife a blind A/B, and she didn’t even need to go back-and-forth. One recording, one take on the ifi, one take on the Chord, and she immediately told me that streamer B (the Chord) was better (over USB). Thorough continued listening confirmed this time and again. Please don’t buy the ifi Zen Stream if you plan on using its USB output. Just don’t. It’s not good. There’s simply a layer of audio goop sloshing about on the soundscape causing you to lose quite a bit of depth and texture and detail. It won’t jump out at you with nothing to compare it to, but as with most things noise-floor related, you know when it’s gone, and when I moved to anything else, it sounded so much better. This unit was on my s*** list and I was sure I’d be packing it up in short order. I assumed the coax output would be, at least relatively, just as bad. So, when I concluded my USB comparisons, I moved over to digital coax and… oh wait, holy crap… what is this!? What streamer am I listening to!? This is… amazing. I was flabbergasted. I was hearing space and microdetails I had never heard in my system. More of the texture of drum heads, echoes of tiny transients reverberating through space, the sound of a guitarists finger against the string - all of these became more available to my ears. Timbre of instruments was more complete and three-dimensional. The comparison to the Chord over BNC is most apt. The Chord is super tight, and transients SEEM sharper, but that may or may not be due to the ifi offering more information “around” the transient, causing it to be perceived as slightly less sharp; I cannot be completely sure. To me, the effect of the blacker background is more jarring than the slight difference in transients - in a good way. The blacker background causes the sound stage to widen and instruments to sound even more separate. Both the ifi and Chord clearly separated themselves from the other contenders over digital coax, and to be clear, the Chord’s background is quite black, but the ifi does have a slight edge here. This unit is a no-brainer IF you plan on sticking to the coax output, and if you don’t typically listen to higher-rate DSD content.
Chord 2go/2yu Summary & Commentary
.+ Best USB performance, by far
.+ Excellent over digital coax (slightly better than USB), and offers both BNC and RCA outputs
.+ Best transient crispness over both output types
.+ Very black background
.- Expensive, at $2,250
.- Silly form factor. Two pieces, and power input is on opposite side of signal output.
.- Quality control. I had THREE 2yu units with faulty buttons (no affect on sound).
.- Wonky app. Very poor visual design, and it was glitchy during setup.
.- Wifi only 2.4G and it did drop out on a few, rare occasions. Not deal-breaker bad, but not ideal.
If you aren’t willing to deal with Chord quirks, don’t even consider this unit. You have to order two, separate pieces, bolt them together, set up via a glitchy app that looks like it’s from 2009, and run a power input on the opposite side of the digital output, so you can’t have it sit cleanly in your setup. Oh, and it’s very expensive. Why would anybody get this? Well, I’ll tell you why: it sounds damn good. Especially if you are limited to a USB input on your DAC, this unit beat out the others handily. Maybe something else out there is better, but not between these three. By far the blackest USB background, and crispest transients. You won’t be disappointed over digital coax either, as that offers a slight improvement over USB. However, if you are using digital coax, the other contenders were darn close, if not better, and at that point, you’d have to really want better performance out of edge-case scenarios. For one, the Chord can handle all the way through 384 kHz files over digital coax; the others top out at 192 kHz. If you’re into DSD, particularly higher rate DSD (over DSD 64), you’d lean toward the Chord, because you definitely need USB for those. Other than that, though, it’s a heck of a lot of money for good performance, but not always the best, with lots of quirks, and stiff competition.
Bluesound Node Summary & Commentary
.+ Good digital coax performance
.+ Exceptional app that integrates with other BlueOS devices
.+ Has a DAC, if needed (no idea how it sounds; didn’t try it)
.- Had some dropouts for higher bitrates, on occasion
.- USB performance was so-so
“Middle of the road” is probably the best way to describe this guy - and that’s not meant in a bad way. It’s a decent value at $600, but not the cheapest. It has good coax performance, but not the best. It has okay USB performance, but not the worst. It does have the best app and features. The form factor is nice. I don’t have a ton more to say about it.
I kept the ifi Zen Stream. My M-Scaler takes digital coax, and the ifi has the blackest background over that input. I do have to downsample some of my highest-res music (I have some 352.8 kHz albums that sound amazing), but the lack of noise floor makes up for the downsampling. At $400, it’s just too big a savings vs the Chord unit to justify a different decision. However, if my DAC only accepted USB, I would have absolutely kept the Chord 2go/2yu despite the price. Its USB performance is that good. As stated before, if you are limited to USB, please don’t buy the ifi Zen Stream. If you don’t want to consider the Chord 2go/2yu for USB, then consider building yourself a NUC-based server/streamer and run USB out of that. It’ll run you about $1K (way less than the Chord pairing), you get a fantastic Roon core as a bonus, and solid USB performance that is meaningfully better than the BS Node and ifi ZS. That’s all, folks. More nerdy details below, if you care.
Testing Setup and Process
My Reference Gear
- PS Audio Stellar PowerPlant 3 (SPP)
- AudioQuest Thunder (wall to SPP)
- AudioQuest Blizzard (SPP to DAVE)
- Chord Hugo M-Scaler (HMS)
- Chord DAVE
- AudioQuest Diamonond BNC cables (HMS to DAVE)
- Focal Utopia
- Norne Silvergarde S3 balanced headphone cable
- All other power cables/supplies were stock
- For USB listening, streamers were connected via a Curious Cable USB cable
- For digital coax listening, I ordered matching AudioQuest Carbon cables, one BNC->BNC (for the Chord 2yu) and one RCA->BNC (for the ifi Zen Stream and Bluesound Node**)
**I actually didn’t have the AudioQuest cables in time before returning the Bluesound Node, but I had an RCA-> BNC adapter and used the stock BNC->BNC cable that came with the Chord 2yu to compare, and the results were clear enough for me to place the BS Node compared to the others. As a matter of fact, my initial impressions were all only confirmed with the new AQ cables, with a very slight overall improvement, but no changes in the relative characteristics.
I skipped my tube amp for this test, as the DAVE’s headphone out is still the most accurate output in my system, and I wanted every last fragment of resolution.
My listening extended beyond these tracks, but I found them to be excellent at revealing differences between the streamers and outputs
“Innocence” on Polarity, by Hoff Ensemble, Enders Jormin, Audun Kleive - A very high bitrate track (352/24) that would push streamers’ outputs to the limit, or if beyond the limit, reveal how they handled downsampled music. This album has exceptional recording quality. Listen carefully to the highly nuanced percussion over the first 45 seconds. See how much space you can hear around the transients. Can you hear them echo through the room? Can you hear the drum head reverberate? The poorer performers lost three dimensionality and a sense of space around the transients. The ifi coax output is amazing for hearing “through” every strike. The Chord coax gave them a touch more specificity in time and space, but a bit less three-dimensionality.
“Fascinating Rhythm” on The Gershwin Connection, by Dave Grusin - Super crisp percussion at the very start. Again, listen for drum heads, space, and echo. Then, when the first piano run comes in at 0:21, this shows off digital glare when present. Is there a sheen to those higher piano notes? An annoying brightness? Did you turn your volume down when they came in? Digital glare. The Chord’s USB is quite good, so the passage is fine, but if you have the iFi or BSN, switching between the two outputs will be a great teaching moment.
“Harlem Nocturne” on Swing’s the Thing, by Illinois Jacquet - Concentrate on the saxophone. Do you hear the subtle growl? You won’t on the ifi’s or BSN’s USB outputs, where it’s smoothed over. The better outputs brought out textures of a real sax, whereas the poorer outputs covered the sax in audio cling wrap.
“Turandot: Act 3. Nessun dorma!” on Puccini: Turandot sung by Andrea Bocelli - How real is Bocelli’s voice? Do you hear the cut at 0:11? Do you wince when he hits a high-note forte at 1:07, 2:47? Better outputs will add realism, detail (you’ll hear the cut between “Nessun” and “Dorma” at 0:11), and you won’t have to wince or turn down the volume at the louder sections because of digital glare