On the Naim forum. A response from a member taken from the thread:-
The problem with the old Mac Mini was the poor jitter response on its optical out which measure on early models at 800 ps. Later models reduced this to around 200-250 ps. A top quality CD transport like the Meridian G08.2 has a random jitter figure of around 20 ps across the audio band. The jitter issue could be remedied by using its USB interface into a USB/S-PDIF converter and then using an optical cable to the DAC. I've never liked the idea of shoving a USB cable up a DAC as this introduces electrical noise. A device like Musical Fidelity's super little V-Link worked wonders. However, plugging a computer straight in to a Naim DAC through USB is not possible and so is not an option for me.
Enter the Lion Mac Mini and random jitter across the audio band is now 10 ps. I am fortunately enough to a have a new Mac Mini in the house. It is not mine and will be used for non-musical purposes in the new year. However, spurred on by the news of its new low jitter digital out, I tried the new Mac Mini with a trust Glass Optical Cable and my Naim DAC/555PS and also UQ. I was also able to compare it with a MacBook Pro and PowerMac both through optical and using the V-Link.
What a revelation - the V-Link was rendered totally redundant. A simple glass optical cable (I recommend the Wireworld Super Nova) produced stunning results. I used Decibel as a player because it played from memory (to be honest I'm not claiming I could hear an improvement over iTunes). The new Mac Mini, with a reported noise floor on CD quality music of -92dB, is one of the quietest transports of its kind.
The advantage of using optical is that it leaves the electrical noises behind and from my listening it works.
I have tried the new Mac Mini in two systems - my main one is Naim DAC+555PS-PL/HL/282-SC-PL/200-PL/Allaes and the office system is UQ/Eclipse TD speakers. I think it is delightful. OS X is so much better than Windows (I still have to use that for work) and it is really easy to control with an iPad and plays just about anything.
Its advantage over the other digital streaming source I own W4S ZP90/Vortexbox is that it'll play hi-res. The Vortexbox/UQ will also play hi-res.
So does the Mac Mini sound better than with CD Quality than the superb W4S ZP90/Vortexbox ... probably not, but it is certainly its equal. I still prefer the Sonos UI to iTunes.
Although, there are lots of other ways to propel music from a computer audio file to a Naim DAC, the best device I've found (assuming you don't wish to stream around the house) is the new Mac Mini. For streaming, it is the Vortexbox.
An article about the Mac Mini can be read with a swift click here; however I have read the full article and it is obvious the author is not that familiar with Apple systems, but nonetheless reported it gave great results.
The Mac Mini I have has a 256GB SSD with OS X Lion and 750GB HDD and is remarkably quiet. The build is surprisingly good - far better than my work PC.
I am thinking to buy my own one of these to use as my music player as I know somebody who would like to buy my W4S ZP90. It would hold my favourite 1000 albums without problem and I'd have the Vortexbox for back-up should something catastrophic happen. I also leave a 2TB disk at friend's house for extra safety.
As always, this is my view of the world, but I prefer Lion Mac Mini/Naim DAC+555PS to any CD player I have heard and it is every bit as good as my Dolby S Cassette Deck and far more convenient than putting all my music on USB sticks. It is only the old trusty LP12 that I prefer.
I just wish I could get a black version ......
All the best, Guy
