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PostPosted: 29 Oct 2011, 10:50 
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Hi folks, I've purchased a Musical Fidelity V-DAC II. The V-DAC II is the new update to the previous popular DAC model by Musical Fidelity, the V-DAC. The MSRP for the V-DAC II is $349, about $50 more than the previous model.
Photos of the V-DAC II
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V-DAC-II.jpg

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V-DAC-II-inputs.jpg

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V-DAC-II-output.jpg

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V-DAC-II-bottom.jpg

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V-DAC-II-inside.jpg

For that extra $50 you get updates in the appearance and finish of the chassis, updating the standard USB input to an asynchronous USB port and improvements to the technical performance. With the asynchronous USB port you can now stream a full 24-bit / 96 kHz. I also tried the one 24-bit / 192 kHz album I have but it looks like the media is down-sampled to 24/96 on the software side before being sent over USB to the DAC.

On the bottom there are two rubber feet that run the length of the enclosure. The audio output from the DAC is via one set of RCA outputs located at one end of the enclosure. The digital inputs are located at the opposite end and consist of a USB (type B) port, an RCA (coaxial) and a S/PDIF (optical) input. There is an input switch which will allow you to select the input mode between either USB or optical/coaxial. The switch is physically small and located in between the USB and coaxial inputs. With both the USB and coaxial inputs in use some may find it a little difficult to get their finger in there to flip the switch, I had no problems. There are two LED indicators, a cool blue for power and a light green to indicate a digital signal lock. Power to the unit is provided by an external 12VDC (500 mA) wall wart type power supply included with the DAC unit. There are no power controls on the DAC or the external power supply. All the connections and controls are labeled on the enclosure. The input selection switch is marked as selectable between USB and coaxial, but it actually selects between either the USB port or both the optical and coaxial inputs. On the inside there is a Burr-Brown SRC4392 stereo, asynchronous sample rate converter and a Burr-Brown DSD1796 stereo DAC (24-Bit 192 kHz).

The specifications note that the maximum output signal is 2.2V. Across 20 Hz to 20 kHz the response is noted as +0/-0.1dB, THD (total harmonic distortion) is 0.004% and the SNR (signal to noise ratio) is -117dB.

Set up of the Musical Fidelity V-DAC II is very simple - just plug the USB input to a computer and the V-DAC II is automatically added as new hardware. I tried on both Windows 7 and Windows XP setups with no issues. Playing music is as simple using your media playback software (I use foobar2000).

I've had the V-DAC II for over a month now. I find the overall sound to be neutral with no colorations. I find the neutral signature to be pleasant, accurate and rich with details and emotion. The DAC is about $349 and IMO the performance is pretty high for this price. The V-DAC II is the perfect all in one package that will quickly get you decent quality audio from a computer. The DAC upsamples so it can also be effectively used to upgrade the aging digital end of your old CD player. Excellent value for the money here.

Cheers


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PostPosted: 29 Oct 2011, 21:25 
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Hi Gio, Good info. I have been looking into DACs for a while and this may be the one to get. Yes I know it doesn't have a single tube, but ..... :? Two things come to mind on the subject. First the most recent issue of Absolute Sound has a lot of information about digital audio and they (the stalwarts of analog) say now that digital is the way to go for source material (wow). :shock: Second I got a flyer in the mail last week from Oppo. They are now marketing a device to allow linking the Oppo players to the internet via an ethernet connection. If I recall (I have to look) it was really inexpensive. With the premium DACS in the Oppo SE series this could be a really cool thing. I can see linking a PC to the Oppo as possibly great way to get into high quality digital music.

Good listening
Bruce

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PostPosted: 30 Oct 2011, 16:34 
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I have also left the steam age and entered the world of PC based music. I have been playing high rez. audio files for some years since I bought my Oppo 980H and now BDP-83SE. These players play DVD-A upto 24Bit/192Khz. Lucky Linn and now HD Tracks have plenty of high rez audio. I believe the LP my just have met its match.

To play high rez files in the past I had to make DVD-As. This requires about four steps to get it off the web and onto a DVD. For AU$149 Jaycar Electronics sell a 24Bit/192Khz compact DAC which will play FLAC at full 24/192 and anything else you care to through at it. The DAC (part AC 1616) is totally powered by your USB port (you could change this) and outputs to Headphones, TOSLINK and RCAs simultaneously. You must load the ASIO driver for this inexpensive DAC runs asynchronously and uses the laptop as a data server only. Foobar is loaded to help organise files.

Don't go looking for a DAC in the AC1616, there are none. I've had the lid off. In this small box is a very powerful DSP and does all converting etc. in software. XMOS (google it and watch the video) have developed a small very powerfull dedicated microprocessor which does all the work. A few other hardware components handled connection to the real world. The DAC weighs a few grams. On top a string of leds will indicate exactly at what bit rate the files are being read. So if you are playing a 24Bit/96khz FLAC direct from the laptop the "96k" led lights. This has proved acurate. Another led flashes to indicate data is flowing ( a bit anoying). Three fixed Xtals lock all clocking so jitter is non-existent.

The DAC works every time, flawless. I compared the sound by first listening to the high rez. FLAC off the laptop through the DAC and then the DVD-A I had made from that FLAC. I synced the two and flipped between them. There is a very slight difference between the two with a slightly weightier sound off the DVD-A. This is the Oppo DACs putting thier signature on the sound. Either one is perfect. Foobar is an excellent organizer and for the convenience of playing FLACs, unprocessed, straight off the laptop I'll be cutting no more DVD-As. Now this will hurt. I'm on staff so this knockout DAC cost me AU$77! You can buy from Jaycar over the internet.
Attachment:
USBDAC.jpg
Attachment:
AC1616ss.jpg


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PostPosted: 30 Oct 2011, 20:46 
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gofar99 wrote:
First the most recent issue of Absolute Sound has a lot of information about digital audio and they (the stalwarts of analog) say now that digital is the way to go for source material (wow).

The more I listen to these new hi resolution digital tracks, the more I believe it too. ;) I'm really enjoying my high res music collection on the computer and this DAC is a good all in one solution. The BDP83 won't stream 24/96, you have to burn the file as Mark indicated. I think the new models BDP93 and BDP95 are much better for streaming.
Cheers

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PostPosted: 30 Jul 2012, 15:17 
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I bought one of these in February along with an outboard 12v 2a regulated power supply and I'm streaming audio from my Imac to my stereo. My system consists of a Conrad Johnson PV-10a, Thorens 316 turntable with Ortofon cartridge, NAD 542c cd player, a pair of BK 200w monoblocks, and a pair of DynaAudio stand mounted speakers with a sub to help out in the low end.

After the new vDac II ran for a week or two it really opened up and sounded pretty sweet. I've looked around and found a schematic and some tips on improving it. Replacing the output caps and perhaps the opamps seem to be a common starting point.

The opamps are surface mount and will be a pita to deal with, any ideas on what might be the best choice (opa2132 and 2134?) for replacements?

I'm retired now so I try to save a buck where i can. I just built a pair of speaker cables using some CAT-3 cable i had down cellar, I'm using 4 CAT-3's for each channel (solid colors for the hot and white for the common) so the net is equivalent to #13 wire. They seemed to clean up the upper end a fair amount and all it cost me was some sleeving, shrink wrap, and 8 banana plugs - probably $40 for the pair.


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PostPosted: 31 Jul 2012, 01:30 
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Since purchasing the Oppo BDP-95 I play a lot of my old music and ALL my new music direct from a USB 2.0 160G HD into one of the two Oppo USB ports. It just doesn't matter what the file format is it just plays it. And I can build a play list.

No my burn'n baby for me.

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PostPosted: 08 Aug 2012, 12:17 
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bobc47 wrote:
The opamps are surface mount and will be a pita to deal with, any ideas on what might be the best choice (opa2132 and 2134?) for replacements?

That is a an upgrade option and should be an improvement over the stock opamps. I would only reccomend this route if you are familiar and comfortable working with small surface mount parts. I've only done it once and decided I won't work on SMT stuff any more as it was very tedious and frustrating with a fine tipped soldering iron. Let us know how you make out.

Cheers

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PostPosted: 24 Sep 2012, 17:08 
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My VDAC II setup sounds just as good as the cd player to my modestly educated ears. The biggest plus I've found is the ability to shuffle through all my music collection throughout the day. This is a huge plus for me. I've rediscovered music I forgot I had...


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PostPosted: 24 Sep 2012, 20:02 
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Just a little off thread but DAC related, I had posted I was using an inexpensive DAC for the first time a few posts back. I have moved on since that point with the purchase of an Oppo BDP-95. Usually I would download from iTunes and burn to black CD. I have drawn a line in the sand and from now on all downloads go to hard drive. No more CDs.

My 160GB USB2 portable HD drive plugs into one of the Oppo's USB ports. From here I can access the Oppos Sabre32 DAC still regarded as the best DAC chips available. My method to get from PC, where the iTunes download resides, to HD is to use "Switch" a ALC converter program. But I up sample the file to a 24B/96K WAV. I have listen to the file converted straight to 16B/44.1K and have found the up sampled version sounds a lot better. Not sure why??

For me there is no going back. No more CDs. I am not back-converting all my iTunes downloads that would take ages but every new purchase goes to HD. As mentioned above it makes music selection and play a snap. I'm sure it sounds a lot better too.

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PostPosted: 26 Sep 2012, 12:22 
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Hi Mark,

A while back I was using a Behringer SRC2496 I found the same thing. Upsampling improved the sound in all cases. in particular, I found that upsampling sounded best when you upsample in whole number multiples. For example, a 16 bit / 44.1 kHz CD sounded best at 24 bit / 88.2 kHz, not 96kHz.

Cheers

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