A stand-alone DAC devoted to the Bluetooth standard, Paul Rigby looks at iFi’s Zen Blue
Who knows? It might sell only burger and chips nowadays but back when I were a lad, Southport’s Bold Hotel was the height of sophistication. Reserved for family treats (i.e birthdays and the like), a trip to “the Bold” would see a swarm of waiters darkening your table. Dishes were served with the manual dexterity of a Las Vegas grifter, dealing you in.
Swanning around the place, you couldn’t help but notice how quirky Southport was and probably still is. A Victorian seaside resort in which the sea is normally about 150 miles away from the prom, the town is bedecked with cast iron filigree that hangs from the covered walkways and old souls that haunt the High St.
This is also where iFi lives.
And it makes sense. Mainly because this hi-fi outfit specialises in quirk. A bit like Monty Python’s Spanish Inquisition, you should always expect the unexpected with iFi and that’s what I failed to do when I was taken completely by surprise with this Bluetooth-only DAC.
A specialist device, here Bluetooth detaches itself from its usual position. That is, shoe-horned into an unfortunate DAC, powered speakers, amplifier, Cornflakes packet or some such. In positions such as those, Bluetooth modules normally make a complete nuisance of themselves because they tend to infuse the things with digital noise.
The mere fact that iFi has separated Bluetooth (including its own power supply) from anything else and put physical space between it and the rest of your hi-fi puts a smile on my face. You can add all the damping technologies you like but there’s nothing like a physical gap to get the de-noise tasks firmly underway.
Dropped into a chassis that looks like a miniature Art Deco console table, without the legs, the Zen Blue certainly sticks out from a typical hi-fi system in aesthetic terms.
I dislike Bluetooth. I like the idea of it. I like what it does. I just don’t like it. Why? Because it’s a perfect illustration of what happens when an open standard goes bad. There are so many variants and standards. Half the time, if you ever send a Bluetooth signal from a device, you’ve no idea exactly what you’re dealing with. There’s more codecs out there than curries.
This means that your receiving device might not support the particular sending codec your source is generously offering.
This is part of the reason the Zen Blue exists and, bless iFi’s little cotton socks, its a very useful weapon in the codec-battling armoury.
Using a Qualcomm 5100 chip, the Zen Blue backs the usual SBC codex but also handles AAC-supporting Apple devices, aptX and aptX HD, Sony’s LDAC and even Huawei’s LHDC! I must admit, the latter is a new one on me. You see? These codecs just keep coming out of the woodwork. And it doesn’t help. Talk about a waste of resources.
Despite the list, the Zen Blue does the hard work. So you just need to pair your device and the Zen Blue selects the best codec for the device. An ESS DAC handles the data processing, calming those jitter nerves to run through custom Op Amps to emerge via single-ended outs or a 4.4mm balanced out on the rear of the chassis. Coax and optical are alternatives, if you flick the rear switch from analogue to digital, running to your favourite DAC. iFi does offer a Zen DAC but I’m going to look at that separately, in a different review. Other items on the rear is a screw connector for a Bluetooth aerial (which does ruin the chassis’ lines, rather) and a socket for a switch-mode power supply
The front of the chassis includes a status window (each codec spouts a unique colour in this window), a pairing button and pairing light.
To begin the tests, I hooked the Zen Blue to my similarly-priced Topping E30 DAC via coax and fed that into my hi-fi. As the Zen Blue is such a low cost unit, budget users have the ideal opportunity here to create a good quality, low cost digital system.
I used my iPhone as the initial Bluetooth source. It might not be aptX HD quality but it’s certainly a step up from SBC and playing a lossy file of Mercy Mercy Me from Marvin Gaye, the output was surprisingly good.
In fact, I don’t think I’d heard Bluetooth ever sound this good before, even from this iPhone. Yes, Bluetooth had that slight midrange hardening, just a tad mind you but I was very impressed by the sheer size of the soundstage. Wide as can be, the extra space allowed the incumbent instruments to really spread out and find a spot of their own. This instrumental separation meant that more detail could be sought by the ear, allowing greater precision to emerge from each.
There was no treble fizz or bloated bass. There was remarkable discipline from this source.
I then switched to a lossless DSD128 file and Eric Bibb’s Meeting at the Building, sent from my MacBook computer via Audirvana Plus.
I was stunned. The quality was magnificent for a Bluetooth stream. The layering of this busy arrangement was handled succinctly. The gamut of voices and instruments on view here held their position, never bumped elbows and retained a rarity that was accompanied by delicate reverb and impressive dynamic reach for a Bluetooth stream.
Just for fun, I then hooked the Zen Blue to a better quality Benchmark DAC priced around £2,000 (again, via coax) to see where that took the sound. Now the slight Bluetooth edge remained, giving the sound a bold solid state presentation (loved by many users, I know) but, in broader terms the treble extended its output, bass was large, resonant and full of character from Charles Lloyd’s How Can I Tell You from the jazz album, Manhattan Stories at 24bit/96kHz. The cymbal hits, pushed way back in the mix during the upright bass solo, were still clean, open and informative while the sax was breathy and characterful.
I then removed the DAC and plugged the Zen Blue directly into my amp via its own single-ended outs and played the 16bit/44.1kHz of Skunk Anansie’s Hedonism. There was a slight rise in noise here as the Zen Blue’s internal DAC was brought into play but the performance remained impressive with its big and bold lower frequency response plus emotionally delivered vocal performance that infused the midrange with detail.
Turning to the Fiio M7 and playing the same music over aptX HD, I was impressed with the clarity and midrange insight but even more bowled over by the LDAC-infused Bluetooth codec which spilled from this device at a higher bit rate, offering greater transparency and bass character. As is often the case with streaming codecs, neither were perfect in terms of sound quality with the specs looking better than the sound reality but, even so, both still provided excellent sound quality. The fact that I could connect to any device streaming LDAC was a novelty in itself, never mind the excellent sonic response. In fact, if you’d like to know more about this Sony codec, check out this link: www.sony.net
If there was ever a specialist digital device, this is it. Any Bluetooth fanboy needs to grab this box because it not only offers untold codec riches for anyone who has committed to this streaming option but it also does its level best to both provide superior inherent sound quality but at a smile-inducing price.
iFi ZEN BLUE BLUETOOTH DAC
Tel: 01279 501111
GOOD: feature laden, price, overall sound quality, easy to use, attention to detail, it’s from Southport
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