View RSS Feed

Conrad65

MF V-link 2, Quad CDP2 and Mac Mini 2011 sample rates query...

Rate this Entry
A while ago I made the happy transition from CD to computer streaming - ripped all my CDs and started downloading. Bliss! Even stopped playing vinyl...bye bye Gyrodec, SME, Koetsu. I was very much aware of the limitations of iTunes, compressed audio files, etc, but felt that Apple was the way to go as I started out with an iPod eight years ago and enjoy Apple products (iPod, iPhone, iPad, etc). Well the latest step was to introduce a Mac Mini in to my hifi world and what a little bundle of joy that has been.

Recently I bought a Musical Fidelity V-link 2 in order to take the digital audio signal from my Mac Mini 2011 via USB to the built in DAC of the Quad CDP2. In my previous set up using the digital optical out from the Mac to the Quad (iTunes or Songbird) the sample rates would be indicated on the Quad up to 96Hz. Now with the V-link inserted in to the chain and output via USB from the Mac the maximum sample rate displayed on the Quad is 48Hz. I have tried adjusting and changing all the audio/sound settings in the Mac without any difference - the Quad still displays a maximum of 48Hz coming from the V-link (using either optical or coaxial). I have also tried using Audirvana, Amarra and Pure media players with the same result - I can only get a maximum sample rate of 48Hz displayed on the Quad.

Does any one ave any ideas about what is going on here?

As an aside to my query I must report that using the V-link produces a dramatic improvement to the sound, irrespective of the my problems of sample rate shown on the Quad.
Categories
Uncategorized

Comments

  1. maelob's Avatar
    I believe the v link II has a sample rate indicator. is it showing the same as the Quad?
  2. Conrad65's Avatar
    Hi Maelob,

    The V-link 2 (I believe MF refer to it as the V-link II) does not have a sample rate indicator - the newer and more expensive V-link 192 has sample rate indicators. I bought this (II) version as I have no music files higher than 96Hz. It has two lights - one shows power and the other that is has locked on to a digital signal.

    The Quad shows sample rates as numerals - when I insert the V-link in to the chain it shows a fixed rate of 48Hz irrespective of the actual rate of the file being played.

    I've tried substituting different cables, using different USB sockets on the rear of the Mac Mini, adjusting every possible software setting in OS, iTunes, Audirvana, Song Bird, etc. I am starting to wonder if it's either the Mac Mini limited to 48Hz on the USB (due to a software or code conflict) or that the V-link is faulty. Hmmmm......
  3. maelob's Avatar
    I know for sure the Mac USB support hi res so not sure what the issue.
  4. Audio_ELF's Avatar
    Starting at first principles... are you using iTunes bare, or with Audirvana / Bit-Perfect or some other software?

    If so, then in Audio Midi, you need to set the output sample rate to the required rate before starting iTunes - i.e. set to 44100Hz for CD rips, 88200 or 96000 for High Res downloads.

    Eloise
  5. Conrad65's Avatar
    Yes, starting at first principles.....I've uninstalled Audirvana and Amarra HiFi and just using iTunes. I start by selecting the V-link / USB for sound output on the Mac under System Preferences/Sound and then select the V-link in Utilities / Audio Midi Set Up / Audio Devices, at the same time setting the sample rate to 96000Hz. When I do this the Quad immediately flashes up 48.0 in its display window. The connection from the V-link 11 to the Quad is via optical. The same thing happens if I substitute the optical for a coax instead. After making the above settings I open iTunes select a 96000Hz file and play....the Quad still flashes up 48Hz in the display window.

    However, if I bypass the V-link and use the optical output from the Mac direct to the Quad, makingthe required settings changes in the Mac, the Quad then the correct sample rate of the file selected in iTunes (44.1, 88.2 or 96) - in effect I am reverting back to my original set up prior to the V-link by doing this.

    So, at a bit of a loss with this now. I will say that inserting the V-link in to the system does seem to make a positive change sound-wise, irrespective of the my sample rate quandary. The improvement is best described as more open and transparent with perhaps a bit more detail emerging and better defined bass lines.

    I think my next step is to try and get the V-link in to a dealer for a check in another system to confirm my current situation. I am also going to buy a V-link 192 (they are being sold at GBP 149 currently - am guessing there is a Mk2 version on the way) and try that instead in my system. Is it really possible the V-link could be faulty?
  6. Audio_ELF's Avatar
    It maybe that the display is just showing the wrong rate. I seem to recall this happening with some DACs and M2Tech HiFace.

    Eloise
  7. Conrad65's Avatar
    Yes, I have considered that.....but......the display shows the correct sample rate when the Mac Mini is directly connected using the optical output!
  8. Audio_ELF's Avatar
    This is from memory so if I'm wrong I apologise...

    A small minority of DACs display sample rate as reported by a code/flag sent by the SPDIF transmitter. In some SPDIF transmitters this flag is not sent correctly so the DAC won't display it right. Most DACs display the correct sample rate information as they calculate it from the data stream rather than relying on the flag.

    Do you have any other device with SPDIF input - a AV Reciever perhaps?

    Also if you select 44100 or 88200 what is displayed on the DAC. I'm pretty sure the 96000 is being received correctly otherwise the output would sound wrong (which I assume it doesn't?)

    Eloise
  9. Conrad65's Avatar
    Hi Eloise,

    Your explanation makes sense....I don't have another device with an SPDIF input to try. Given that using the V-link 2 results in a fairly significant improvement in audio quality (to my ears) I think you are probably on the right track.

    Irrespective of sample rate selected in Midi in OS (41.1, 88.2, 96) the Quad always shows 48 (when using the USB output through the V-link 2).

    As an aside when using a Sony PS3 (music or movie) connected using the optical output to the Quad DAC I get the same result (48 displayed on the DAC) no matter what sample rate output is selected in the PS3 menu!

    Anyway, I am very happy with the sound improvement achieved using the V-link 2 and think I'll stick with it for the time being rather than switch to the V-link 192.

    My next move will be to reinstall Audirvana!

    Conrad65