DAC/Sound Card Confusion

[corbin]

Hey guys,

I currently have a Sansui G-9000 Receiver powering a pair of RTi8's... besides the speakers sounding a little bright it sounds fine when the source is my CD player. When, however, I connect my receiver to my computer's onboard audio there is a noticeable decrease in sound quality.

Now, I'm sure this is because onboard audio sucks, and I was originally going to get a soundcard to remedy my problem until I realized that my money would probably be better spent on a DAC... and this is where my confusion arises. Wouldn't the signal from the computer going to the DAC be degraded by onboard audio, thereby not giving the DAC a quality enough signal to even do anything with... or is that why I should be using an optical output to connect the DAC to the computer?

Anybody have any suggestions for a DAC for under $200 that would do what I need?

 

[Adam]

I believe that onboard audio continues to improve, but it is entirely possible that your onboard audio does suck. When I went from onboard audio in an HP desktop back in 2004 to a Creative soundcard, it was a huge improvement. I wouldn't count out a soundcard if I were you. You should be able to easily get improved audio for much less than $200 by going that route.

... or is that why I should be using an optical output to connect the DAC to the computer?

As for an external DAC, you would certainly need to connect a digital audio signal from the computer to the DAC. After all, that's what digital-to-audio conversion is all about. Does you computer have a digital audio output (either optical or coax)?

 

[dem beats]

I am not well enough versed to give you the true explanation. But from my experience, a new sound card can make worlds of difference. I would think it to be much much better to solve your problem that way, than to add another component.

I was much more impressed than I thought I would be.

 

[corbin]

As for an external DAC, you would certainly need to connect a digital audio signal from the computer to the DAC. After all, that's what digital-to-audio conversion is all about. Does you computer have a digital audio output (either optical or coax)?

Yes, it does. That means that all I need is an optical cable and my coax cable to be between the DAC output and my vintage receiver, which only has analog, right?

I am not well enough versed to give you the true explanation. But from my experience, a new sound card can make worlds of difference. I would think it to be much much better to solve your problem that way, than to add another component.

I was much more impressed than I thought I would be.

Seems like a buying something more "dedicated" and "one purposed" like a DAC is better than buying a "jack-of-all-trades" sort of product, i.e. soundcard... but I don't know much about audio so I could be wrong? I personally think the difference you saw after changing from onboard to a sound card WAS huge, but not necessarily as huge as what could be achieved from a DAC.

 

[Adam]

Keep in mind that if you buy an outboard DAC, then you are buying a product with relatively low production volumes (because not many people care to buy those). So, it costs more because of economies of scale, and it costs more because you're paying for the packaging (the nice looking box, knobs, and so forth). Sound cards benefit from (a) being mass produced and (b) not needing any fancy packaging - they are bare circuit cards that plug into slots inside of your already existing computer case.

So, don't be too sure that an external DAC of similar cost is going to be any better than a good sound card. Honestly, I think that you'll be better off with a sound card.

That said, don't let us talk you out of a DAC is you just happen to want to give one a try. You would run the digital audio from the computer to the DAC, and then the analog audio from the DAC to your receiver.

 

[avaserfi]

You could just get an outboard DAC/Soundcard that is superb for both applications [and many more] while staying within your budget. The E-MU 0404 USB 2.0 is a superb computer interface that is a top quality mic preamp, headphone amp, ADC/DAC, unbalanced/balanced, coaxial and optical I/O. The units street price is about $200.

 

[fmw]

It isn't the DAC chip itself. Those all perform about the same. The problem is that your sound card has circuitry appropriate for a clock radio's audio rather than that of a a high fi system. You may also be dealing with a wide impedance mismatch since the sound card is not only a preamp but an amplifier as well.

If you want to do it right, find yourself an outboard computer interface that connects either with firewire or USB. These are the units that recordists use to interface their microphones, midi and line level sources to their computers for recording. The one I use, as an example, is the Edirol FA66 which is a firewire type of unit. It is more powerful and expensive ($280) than you need but you can find all kinds of these interfaces at any of the pro audio sources in a full range of prices. One of these sources would be http://www.sweetwater.com

I realize you don't need mic inputs and ADC's but these units have them just like computer sound cards have them but they are of superior quality to computer sound cards. The only issue you will encounter is that the analog outputs on these units are usually 1/4" phono plugs so you will need a pair of phono to RCA cables to interface with your receiver. The analog outputs will be line level so you don't need to worry about plugging an amp into a preamp. These units can be bus powered through USB or 6 wire firewire connections. You can use an inexpensive one because all you will give up with inexpensive ones is expanded recording capabilities.

The other option would be to buy a consumer sound card of better quality than what you have. Sound Blaster and others have these cards. They are not as good as the outboard interfaces described above, however.

 

[gus6464]

I believe that onboard audio continues to improve, but it is entirely possible that your onboard audio does suck. When I went from onboard audio in an HP desktop back in 2004 to a Creative soundcard, it was a huge improvement. I wouldn't count out a soundcard if I were you. You should be able to easily get improved audio for much less than $200 by going that route.


As for an external DAC, you would certainly need to connect a digital audio signal from the computer to the DAC. After all, that's what digital-to-audio conversion is all about. Does you computer have a digital audio output (either optical or coax)?

Optical toslink or coax are not really digital. The signal that passes through the cable is an analog signal.

If you want a pure digital signal out of your computer to the DAC you have to go either USB or firewire.

 

[fmw]

Here's a competent USB computer audio interface that even has RCA analog outputs.

http://www.sweetwater.com/store/detail/FastTrackUSB/

 

[gus6464]

Here's a competent USB computer audio interface that even has RCA analog outputs.

http://www.sweetwater.com/store/detail/FastTrackUSB/

Does the mic preamp on that unit provide phantom power?

 

[Adam]

Optical toslink or coax are not really digital. The signal that passes through the cable is an analog signal.

I have never heard that before.

 

[corbin]

What everybody is suggesting (basically a fancy, standalone soundcard) would be ideal for what I need. Thanks everybody. I know its important to have a digital out from your computer if you want to run music from it.

That said, would would be the best around $230?

I know this,
http://www.emu.com/products/product.asp?product=15185
would do everything I need but I'm all about getting absolute best product for my money so is there anything else I should know?

 

[fmw]

Does the mic preamp on that unit provide phantom power?

No, it is really designed for consumer use. Something like my Edirol FA66 has two XLR mic inputs in the front that can be phantom powered. It also has 2 line level inputs and two S/PDIF inputs in the back and it has a total of 4 analog outputs as well as a stereo S/PDIF output. It is way more than the OP needs. The little M-Audio unit would be fine for his use. If you want to do some serious recording I'd upgrade a little from that $100 unit.

Of course, it isn't expensive to get a small phantom power supply that you can tape to your mic stand. But adding that to the M-Audio interface would put you in the price range of a more versatile interface.

 

[fmw]

What everybody is suggesting (basically a fancy, standalone soundcard) would be ideal for what I need. Thanks everybody. I know its important to have a digital out from your computer if you want to run music from it.

That said, would would be the best around $230?

I know this,
http://www.emu.com/products/product.asp?product=15185
would do everything I need but I'm all about getting absolute best product for my money so is there anything else I should know?

Whatever lights your fire. The little M-Audio unit I suggested is fine for what you want to do. An upgraded unit would just provide more flexibility. More channels, ins and outs, XLR connectors, phantom power and so forth. If you want to spend more, then pick whatever appeals to you. These are just interfaces with ADC's and DAC's and connectors for various types of input. There isn't anything magical about their sound. All are quiet and accurate. That's what your sound card isn't providing that these will provide. Recordists don't choose them for reasons of sonics. They choose them to fit their recording requirements.

Just as important. These units output line level signals, not amplied signals like a sound card. That means they won't produce any audio except with headphones but they will interface properly with your receiver or preamp to provide amplified sound. The sound cards are awful in this respect as you already know.

As an example my next interface purchase will be this one. http://www.motu.com/products/motuaudio/828mk3/. It has 24 inputs and 30 outputs and full mixing capability as well as onboard digital effects. You don't need any of that stuff. No reason for you spend the money for one of these. You just need a connection to the computer, a DAC and an analog output. They all have that.

I should mention that firewire is better for recording because it produces less latency. For pure playback, latency doesn't matter so a USB model would be fine.

 

[MDS]

Optical toslink or coax are not really digital. The signal that passes through the cable is an analog signal.

If you want a pure digital signal out of your computer to the DAC you have to go either USB or firewire.

Slight misperception here...

How would digital data flowing over a coax cable (wire) be any different than the same data flowing over a USB or Firewire cable (also wire)?

Digital data is a sequence of ones and zeros that represent the signal rather than the signal itself (analog). To send digital data over a wire requires a modulation scheme and there are many...the data is modulated onto the wire by using varying voltages or varying pulse widths at a constant voltage or ... (depends on the modulation scheme). So yes, 'digital' data is an analog waveform when transported via a wire but it doesn't truly become analog audio such that we can hear it until the data is converted to analog by a DAC.

 

[Headfoot]

I run a M-Audio Revolution 5.1. It's a steal at $85 because it has the same quality DACs as their Audiophile-192 card which is significantly more expensive.

It can decode essentially all of the DVD-Audio formats (from 192khz 24bit 2 channel to all of the multichannel ones that do not exceed 5.1) with the right software.

It also sounds very good in a perceptual sense. When I put it in instead of my onboard sound I was very happy. It sounds nicer than my Onkyo DX-C370 CD player. I have yet to actually attempt to play DVD-Audio on the card, so I can not say for sure if it works or not.

It works in Vista and XP. It's kind of a pain to get to work in Vista though.