Tim will giggle at this, as for YEARS I've resisted the temptation of adding a music-streaming source to my system, mainly because of all those I'd heard (and there have been many to date, at varying price levels), I'd yet to hear a solution good enough that I could live with, particularly in terms of ease of use, and that could compete on sonic terms with my Sony CDP/DAC, and indeed my turntable.
All that changed recently, when two friends (Ian Walker and Duncan, A.K.A Tubehunter) visited Marco Towers, bringing with them a Raspberry Pi 2 (Model B), a USB hard-drive, filled with various choons, and the wherewithal to connect it all up and demonstrate it to me in my system.
Cutting to the chase, I was gob-smacked at what I heard, as this is the first time that I've listened to a streaming system that didn't sound thin, flat, tonally grey and very 'digital', the complete antithesis of the weighty and purposeful, musically addictive and rich, 'analogue-like' sound, delivered by my Sony CDP and DAC.
What I was hearing this time, from FBA (with the Pi in the equation), had all the latter qualities, together with beautiful filigree detailing and huge globules of musical information, all contributing to deliver thrilling amounts of insight and 'fun factor', with all recordings played - and most importantly, minus any 'digital glare': an effect which to my ears, up until now (to varying degrees), has plagued every digital replay system I've heard, filed-based or otherwise.
This had none of that. What I was hearing was truly 'analogue-sounding digital' (in the right way), with added 'grin-factor' - and hugely entertaining it was, too!!!
However, that *only* happened when we took the preamp out of the equation and listened to the Pi (fitted with an IQaudio Pi-DAC+), directly into my Copper amp, or the equally stunning sounding Quad 405s Duncan had modified into monoblocks (more on those later). With the Pi used into my Croft preamp, the sound was still very good indeed, and perfectly acceptable, but the real magic only happened when the Pi was used directly, being controlled via Volumio, on my Macbook Pro.
Most folk I've read with a Pi seem to use it with a HiFi Berry Digi+, and connect it to a separate external DAC, thus necessitating the use of an optical or coaxial digital cable, and the subsequent (and unavoidable) jitter such cables introduce, thus diluting the purity of the audio signal. Well, having heard just how mind-blowingly good the Burr-Brown 32-bit IQ Audio DAC is (for details, see here: http://iqaudio.com/?page_id=454), used internally and direct, I can honestly say there's most likely little point in using a 'fancier' and more expensive external DAC, as this little thing delivers utterly KILLER sound, at sweetie-money prices... £32 to be precise!!
Ian Walker considers that it outperforms the DAC inside his Rega Isis, which is, what, an £8k CDP? That gives you an idea of the quality of the cheap-as-chips IQ-Audio DAC, and level of sonic performance obtained, when used in conjunction with a Raspberry Pi...............!
Now I've taken my heavily-modified Sony DAC (acting as my current benchmark) to many meets and bake-offs over the years, one of which was the most memorable, was putting it up against the DAC inside Martin T's superb and rather expensive Ayre CDP, and it certainly didn't disgrace itself, in fact outperforming it in some areas, notably bass authority, rhythm and timing and overall musicality, to the ears of the assembled listeners, including Martin himself and MikeMusic, who was also present.
The Sony has also been demonstrated at Scalford, as part of a much praised AoS system, and numerous other places where discerning ears have revelled in its highly addictive music-making abilities. Well, I can tell you that the Pi/IQ Audio DAC combo, streaming hi-res 24-bit files, connected directly to my Copper amp, and controlled on my laptop via Volumio, produces a sound that is well up there with the Sony and in some areas betters it (namely ultimate musical insight into recordings, reduction in perceived 'noisefloor', and all-out detail retrieval), most likely down to the higher resolution of the files streamed, compared to what's available in that respect from Red Book CD.
However, I also suspect that this particular DAC chip succeeds to eke out just that bit more musical information from recordings than the TDA1541s in the Sony, but most importantly, it does so without sacrificing hardly any of the Sony's muscular authority - and it is *that* last factor that has succeeded to turn my head and finally embrace the joys of FBA! Make no mistake: by ANY sonic standards, the Pi/IQ-Audio DAC is a killer combo, outperforming some DACs costing many thousands of pounds, and at a combined cost of around £80, offers just simply bonkers SPPV!!
This is genuine 'giant-killing' performance, no question about it, and probably one of the most exciting discoveries I've ever made in audio. The Pi/IQ-Audio combination is definitely going to worry some high-end companies producing expensive music streaming devices, as here you have all of their performance (and more), without the unnecessary frippery and huge price tag!!
As such, I cannot recommend the above combo highly enough, to the extent that it would be simply ludicrous now to recommend the use of any modern CDP, at virtually any price, as properly partnered and set-up, the Pi/IQ Audio DAC combo, IMO, is likely to sonically outperform it. The respective manufacturers have got it *so* right with the designs of both items, by most importantly keeping the signal path as short as possible and using genuine bit-perfect transfer of data. It is so good that I would confidently put it up against any so-called 'high-end' streaming source, costing many thousands of pounds.
In that respect, it will be interesting to hear what the dedicated linear power supply, which Duncan has built, adds to the party. Full details of that to come... However, for the meantime, I'll be sitting back enjoying going through and listening to the 2TB worth of files I've just obtained from a friend's CD collection, and revelling in how shockingly believable and lifelike the music sounds...
Honestly, folks, try using the Pi without an off-board DAC and digital cable, or a preamp, and instead, direct with neither (into a quality power amp), with a built-in DAC from IQ Audio. Quite simply, you need none of the former to build a high-quality streaming device, capable of top-notch audio performance.
My advice? Well, what are you waiting for?? Just go out and BUY a Pi - it's even tastier than the famous porky ones from Melton Mowbray!
For reference, the following streaming set-up now in situ, chez-Marco is:
1 x Raspberry Pi 2 (Model B) in 'Ninja' case, with Raspberry switch-mode PSU.
1 x IQAudio Pi-DAC+.
1 x Maplins 8G Class 4 SD card.
1 x NAS (shuttle) box with 2TB of music, contained on two hard-drives.
15m of Maplins Cat-5e RJ45 patch cable (connecting NAS box/hard-drives and router, to Pi).
1 x pair of 0.5m Klotz MC5000 interconnect cables, fitted with MS Audio RCA plugs (to connect IQ-Audio DAC directly to Copper valve power amp).
Volumio operational interface (with Kernel parameters set at 'Buscia'), used with a Macbook Pro.
Total cost (excluding laptop and router): less than £350.........
NAS (shuttle) box (containing 2TB of choons, many of which are high-res 24-bit):
Raspberry Pi (with IQ-Audio DAC inside):
Volumio (with Macbook Pro):