Sound Card vs DAC

[rollo]

  Has anyone compared any ? Are we barking up the wrong tree as audio guys ?
   If using a USB connection which is not  the optimized connection losing anything to a sound card ?
    Just makes sense to me to use a sound card instead of the DAC of the month. Check out the Asus Xonar Essence ST at $200.


charles

[jsaliga]

  If using a USB connection which is not  the optimized connection...

What??  In what way are USB connections not optimal?

--Jerome

[richidoo]

Analog signal inside a computer box is a bad idea. I don't think there are any audiophile quality internal sound cards made now. Card-D was good, but now defunct. Lynx22 is good for the money, but it is intended as pro audio card built to a price, with opamps and surface mount caps galore, not to mention D-sub output connectors.

On the other hand many high end audio companies have developed USB DACs which offer extreme performance and refinement. Ayre QB-9, Wadia 121, Antelope Zodiac, Sim Neo380, exaSound E20, these are among the best digital conversion available, all use USB to connect to a computer.

There is still plenty of crap for sale in USB "audiophile" DACs. Older USB 1.1 and some 2.0 DACs were/are still limited in bitrate and jitter rejection, but the newer batch in the last couple years has solved those issues, and they cover a wide price and performance range. Look for "asynchronous" to describe the newer variety, or look for sample rate via USB over 24/96.

[JBNY]

I agree that an audio card in the computer is not the best solution, too many ways noise can get to the analog signal.

Asynchronous USB OTOH is probably the most ideal solution right now. The protocol is mostly immune to all but the most extreme noise, has error checking as well as, most importantly it allows the computer to send the audio as data packets. This is pretty important for audio as it allows a bunch of things to happen. Noise from the PC and on the line becomes much less important than in the past, the data is now sitting in packets that are controlled by a clock on the USB device not the PC, this allows the packets to be pulled by the USB device according to it's ability to process it based on it's buffer. Each packet has an CRC bit that allows the USB device to check the integrity of each packet. These two aspects combined allow a much better chance of perfect audio than we have ever had before.

To keep this brief, what AsycUSB does is make the computer largely irrelevant, a $200 PC should perform the same as a tricked put $5000, PC. Everything inside the computer doesn't matter as long as it can send uncorrupted packets via USB. This is the same kind of transmission that network cards (routers and switches) have been doping perfectly for decades, and even the cheapest devices can now send jitter free packets over the network.

Now all this has happened very quickly (say the last year or so) for audio. Look for USB devices that support USB Audio Class 2. That spec supports up to and over 24/192, using native drivers on most versions of Linux, including MAC. Windows 7/8 shipped without Audio Class 2 certification so most times you need to install a driver.

I've been doing computer audio for over 10 years at this point. IMO it is a much easier now to get fantastic sound using PC audio than at any other point in time.

[rollo]

  If using a USB connection which is not  the optimized connection...

What??  In what way are USB connections not optimal?

--Jerome

  www.buzzle.com. go to USB vs Firewire article. Go to topics. fund "F" and go to USB 2.0 vs Firewire. Hope this helps. I'm no expert.

charles

[JBNY]

In an ideal world, FireWire is probably more ideal than USB. But USB is widely supported, and the features it has are more than what USB audio needs. USB 2.0 is more than fast enough for even 24/192 digital Audio streaming. USB might have a shared bus, but for computer audio that just means the computer needs to be involved with the handling of USB resources, most people put the USB DAC on a dedicated port so the kind of USB allocation issues that might happen using a hub don't really apply.

[jsaliga]

  If using a USB connection which is not  the optimized connection...

What??  In what way are USB connections not optimal?

--Jerome

  www.buzzle.com. go to USB vs Firewire article. Go to topics. fund "F" and go to USB 2.0 vs Firewire. Hope this helps. I'm no expert.

charles

Thanks Charles but I won't bother reading it.  I'm quite secure in the knowledge that I am getting excellent sound quality from my USB DAC.  I was also quite happy with the coaxial digitial connection that I used with the last DAC I owned.  With my new Teac DAC there is slightly lower measured jitter using asynchronous USB than there is with coaxial or TOSLINK, but I cannot detect any audible differences between them.  The reason I use a asynchronous USB connection is because it is required to stream DSD to my DAC.

Good luck with your search for audio perfection.

--Jerome

[djdube525]

The PCI bus can be very noisy (most of my sound cards were PCI based) RF wise... There can be quite a bit of RF inside a case...

Arguments of USB vs Firewire vs Thunderbolt could certainly be made... However USB based DACs will certainly have a large advantage due to the lack of noise.

My 2 cents...

Dave

[richidoo]

I use a firewire 8 ch audio interface, Presonus Firepod for recording, speaker and room measuring, and active speaker experiments. It sounds very good. Firewire was SOTA for pro audio back in 2005 when USB was still just for data transfer, mice and printers. I've made some sweet recordings with the Firepod. I think it is better at ADC than DAC, due to the discreet class A mic preamps, but it's still very good sound for a multichannel DAC too. You had to go firewire back then to get hi-rez audio.

Thanks for the details Joe.

[DaveC]

USB is the solution of choice for almost every DAC these days, now that asynch w/ hi res is pretty much the standard it seems like that's the way to go.

I hear you about DAC of the month, but it's a rapidly changing technology so that's unavoidable. I can see it settling down over time though, soon every DAC is going to be able to handle 24/192 and DSD.

Jerome, it's the DAC that is asynch or not... you don't really have a choice in the matter.

[jsaliga]

Jerome, it's the DAC that is asynch or not... you don't really have a choice in the matter.

Care to cite an authoritative technical reference?

--Jerome

[mgalusha]

I have an ESI Juli@ PCI sound card, it will manage 24/192 and has single ended and balanced outputs. It's pretty good but either of my USB fed DAC's (Lindemann and AURALiC) are more pleasing to listen to. The Juli@ of course offers A/D capability, which is nice for measurements and in fact that is why I originally bought the card, it was for measuring in the shop but has since been phased out and moved to my work desktop where it works quite well.

I also have a TC Electronic Impact Twin Firewire 24/192 AD/DA and like Rich I use it for measurements and recording. I've captured a few LP's at 24/192 and they sound quite good but I think the A/D is better than the D/A. Both the Lindemann and AURALiC sound better for playback. I don't know if the Juli@ is any better than the TC, I suspect it may be on playback.

I think the implementation inside the device is far more important than the interface to the computer in terms of USB vs Firewire. Sticking the card inside the box is fraught with opportunity for noise though the Juli@ is very quiet.

[DaveC]

Jerome, it's the DAC that is asynch or not... you don't really have a choice in the matter.

Care to cite an authoritative technical reference?

--Jerome

No. This is pretty basic stuff, you can do your own research... and I highly recommend you do a lot more research based on your posts. Asynch clocking in a DAC is based on the design of the hardware inside the DAC.

[JBNY]

At this point I think if you have a DAC you are happy with, your best bet is to get a USB to SPDIF converter that is asynchronous as well as has galvanic isolation, I would look for USB converters that are based on XMOS USB chips, they seem to be the best right now for USB support. The world of DACs seems to move slower than the interface to the PC. You can get USB converters, real good ones, under $500 with the sweat spot around $250. Then in a few years when this stuff is old hat, plunk down the cash for a nice all in one unit.

[bpape]

Why convert to SPDIF?  If you already have it in a format where you can trust the impedance, then stay there, or swap to i2s.

Bryan