USB SQ, what can one expect

Red - if the Cantata utilizes the power provided via the USB cable then see this post...

http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1418927833&openmine&zzWilliewonka&4&5#Williewonka

USB power can be unstable and noisy and degrade the quality of data.

If it does not use the USB supplied power then this will not make any difference.

The quality of the USB cable can play a significant part in playback SQ, so get a half decent cable - like the one in the above link.

You also want to make sure that JRiver is configured to send the unaltered digital content without first processing it in some way.

Unfortunately I know nothing of JRiver, so I cannot help with this, but I use an iMac - and the internal Apple software is not great for streaming playback - I use Audirvana to bypass the Apple software.

Personally - I have compared streamed content via USB to the exact same CD content via spdif into the very same DAC and could not tell any difference, so you should be able to "tune" your streaming path to get CD quality sound

Regards...

Red - just this week I've been ripping CD's with dbPoweramp.

The improvements were significant - then again I was using iTunes prior to this - won't ever do that again

You can get dbPoweramp for a free 21 day trial - just google them.

The improvements I noticed were a more believable spatial presentation, especially on live tracks, but even studio recordings were much more life-like. The high-end was also much better.

One of the audio stores I frequent gave me the tip. He swears by it

Give it a whirl and see what you think

Regards...

Cerrot - some might say - you are talking out of your USB port :-)

Perhaps you are correct if you are referring to USB 1.0 ports in both computer and DAC, but with asynchronous USB 2.0 in both - it's a whole different ball game.

Especially if the DAC is designed specifically to handle asynch USB 2.0 data transfers

Is it the best method? - who knows - but it is now so much better than it used to be and if you are that persnickety you'll take another approach.

Once ripped with DBPoweramp - I think anyone will be able to see just how good asynch USB 2.0 can be.

Regards...

Cerrot - please don't interprit this post as me being argumentative, since I am all about getting to the bottom of things and the USB vs S/PDIF debate has been ongoing for some time.

I just did some surfing on the web and found this article, which seems to indicate USB is quite capable of quite high resolution playback. It appears to take a little more "scientific" approach, rather than the "personal observations" posted on many forums, which can be "coloured" by many other factors in any given audio system

http://thewelltemperedcomputer.com/Intro/SQ/USB_SPDIF.htm

EXA's post on this forum supports the above

USB to DAC vs. USB to SPDIF then DAC

But then he made this comment...

Asynchronous USB interfaces are not sensitive to the quality of the USB cable.

I have personally experienced better USB cables do make a discernible difference i.e. in my system!

Since I'm no expert in this field it's always useful to get the opinion of others, so if you could take time to read it and provide some feedback, I for one would appreciate it.

If you know of other counter arguments on the web it would be most helpful

I tend NOT to believe everything I read on the web on first read, so feedback from others is crucial in order to arrive at a more informed conclusion.

If anyone else has "scientific proof" one way or the other, your feedback would also be appreciated - by me at least :-)

Many Thanks in advance

One other way to reduce/eliminate noise on the USB cable is to use the dual USB cables such as the one I identified on my first post of this thread

And we come full circle :-)

Back to the tunes

Cerrot - you are correct...

Simply put...
- USB does send data in packets
- each packet contains a CRC - Cyclic Redundancy Check
- the CRC tells the DAC whether the packet received was identical to the packet sent
- Asynch USB allows the DAC to request packet re-transmission
- if incomplete the DAC requests the same packet until the CRC indicates the packet is complete
- even if the CRC is corrupted the DAC simply requests the packet again
- the DAC then assembles the data stream once complete and plays it.

If this did not work the DAC would simply stop playing or skip - which in my case it does not.

This is the same technology used to transfer the spreadsheets and accounting info of Fortune 500 companies - and it works - otherwise computer systems in general would fail miserably - they don't

S/PDIF does not have CRC checks and balances and therefore you NEVER know if bits are getting dropped.

Yes - there may be other issues with USB, but transferring the correct data stream to an Asynch DAC is not one of them

Here's another link
http://www.thewelltemperedcomputer.com/KB/USB.html

Is it the perfect solution - maybe not

But it is NOT as bad as you are portraying it

I think it really depends on which USB approach a specific DAC manufacturer has implemented.

I have observed power issues with DAC's that power the USB circuitry via the USB cable, which most quality USB DAC's tend to avoid

Regards

Redcarrera - zmanastronomy had this to say about his JRiver implementation...

"The optimizing program I'm using really make a huge difference. It's about the same improvement as I get using the V-Link over the Bifrost alone.
Fidelizer is the name of the program. Huge jump in 3 dimensionality and separation of instruments. It shuts down all the crap in the background of windows and makes my laptop a music server."

Contact him via your Inbox for more details

Hope it helps

Cerrot - I'm assuming the spdif output you are using is on a seperate sound card - which one are you using?

What others have you tried?

Thanks