DAC Question

[admin_exported]

I'm planning on getting myself a good high-quality home theatre PC this summer. My question is, do I need an external DAC?

I will be getting a high end soundcard (Asus Xonar HDAV) so I'm not sure if this will have sufficient music decoding quality or not.

Another thing to consider is that this will be used big time for movies and games aswell as music so will a DAC do 5.1 multichannel sound along with stereo?

I really have no idea about what sort of connections one would find on the rear of a DAC so maybe someone can help me out here...

 

[The_Lhc]

DACs are usually just stereo, integrated AV amps will have their own DACs for 5.1. Which amp were you think of getting?

 

[Anonymous]

To be totally honest I'm not entirely sure how much to spend on an AV Receiver. I was thinking at a stretch I could go for the new Sony STR 5400 (I think that's the one that recently won the AV receiver Supertest) but I might have to tone it down to a ~£1000. I was planning on going for something in the range of the Tannoy Revolution Signature package or a B&W 600 package (603 fronts 605 rears).

 

[The_Lhc]

Right, well you won't need a seperate DAC for movies then, just plug the optical out from the PC into the amp. You know you won't get HD audio that way don't you?

 

[Anonymous]

I was going to use HDMI, not optical because I do want True HD and Master Audio. I'm just wondering if or how a DAC could fit into this setup for musicl playeback. Would I have to switch the cables whenever I wanted to play music or something?

 

[professorhat]

Wouldn't need to switch cables, but would probably need to change a setting on the PC to tell it to output audio via the optical / coaxial output when listening to music.

 

[Anonymous]

I see. And the coax/optical would then go to the AV receiver and to the speakers. Just 2 questions then.

Does DAC make a noticeable difference over and already good soundcard?

What kind of entry level DAC is recommended?

 

[professorhat]

Ah, well, I was assuming your optical / coaxial output was going to an external DAC for music - there shouldn't be any reason you would want an HDMI connection and an optical coaxial connection both going to the amp as this should produce exactly the same sound (in theory anyway!).

On whether an external DAC would make a noticeable difference compared to the DAC in the amplifier, this is entirely down to what products you are looking at. Price gives some indication in quality, but until you've heard it, it's impossible to say which is better than what.

 

[Anonymous]

Well I would want the HDMI for the HD audio and also for the video (I plan to play Blurays off the PC).

Does this mean that some AV receivers could give sound quality similar to lower end DACs?

 

[Anonymous]

You can play music with an AV amp and you will get full HD audio if you use HDMI via the Asus Xonar HDAV as that provides the HDCP to prevent downsampling.

My current setup set up is from an ATI Radeon 4850 HDMI SPDIF option to Yamaha RXV 1900. I use Foobar2000 with WASAPI mode. The music sounds good. However the music sounds better if I play from my DV7001 via HDMI PCM to the Yamaha, I assume because the DAC is better suited to music.

If you want better music quality then you could use OPTICAL/COAX SPDIF from sound card to an optional DAC such as DACMagic or the Beresford and then analogue RCA back to the amp. Use the HDMI direct to amp when watching movies. Probably will need to change default output on the PC though each time.

 

[professorhat]

Ci4N:Does this mean that some AV receivers could give sound quality similar to lower end DACs?

Absolutely, and some could give better sound quality than running it through budget DACs. So, it really depends what AV receiver you get and what DAC is in it. Once you know this, you can start comparisons on external DACs to see how much you would need to spend to improve on it (if indeed you actually still wanted to).

 

[Anonymous]

Thanks for the help guys. I wouldn't mind switching cable too often but there's no point in buying a DAC if an AV receiver can do the job fairly well. The only thing that would cause me to hesitate would be that I've heard most AV receivers don't do music too well. I've actually never tried listening to music out of an AV receiver (only movies) so I couldn't really comment on it. Has anyone else got experience in this area?

 

[professorhat]

True, AV receivers will never be as good as an equivalently priced stereo integrated amplifier (in fact, as a general rule, I've heard that you should expect an AV receiver to be about the same as a stereo amp of around a third the price with music). However, we were mostly talking DACs here and that's not really too relevant in terms of this difference as most stereo amps don't have inbuilt DACs anyway. It's what happens after the digital to analogue conversion which determines why stereo amps are better than AV receivers for music.

 

[Anonymous]

If I was you I would go to your local dealer and ask for some demos. Try some music through AV amp and then separate DAC. Just for good measure try a stereo amp and then you will know what is acceptable to your ears.

 

[Anonymous]

So stereo amps don't have inbuilt DACs but multichannels do...

I will indeed have to try it out.

When I do buy my system, how do I set it so the digital to analogue conversion takes place in the amp or DAC rather than in the PC?

 

[professorhat]

Using a digital out should ensure this i.e. if you use HDMI or digital optical / coaxial, the signal will be sent digitally so no digital to analogue conversion will have occurred until it reaches the amp, whereby the signal will be converted to analogue so it can be sent to the speakers.

If you use the PC's analogue out connections on the other hand (e.g. RCA phono connections), then the DAC within the soundcard will have to be used since you are then sending the signal in an analogue format.

 

[The_Lhc]

Ci4N:

So stereo amps don't have inbuilt DACs but multichannels do...

That's always been the case up until recently, but if you check the review section you'll find more and more integrated stereo amps coming to the market.

 

[Anonymous]

Okay I think I get it now. Just out of interest, would it even be possible to get sound from PC to stereo amp with one of the less modern ones (i.e. an amp without integrated DAC) without buying an external DAC?

 

[Anonymous]

Ci4N:Okay I think I get it now. Just out of interest, would it even be possible to get sound from PC to stereo amp with one of the less modern ones (i.e. an amp without integrated DAC) without buying an external DAC?

You could use the PC's 3.5mm headphone jack connected to one of the amps phono inputs.

 

[professorhat]

Indeed - basically depends on your soundcard's outputs. Most will have at least the 3.5mm output, some will have RCA phono outputs.

 

[Anonymous]

Your best bet to play music and audio through the amplifier from the pc without a Dac is Chords Ichord. Very good quality 3.5mm headphone jack to 2 phono connector. I used it before I got a Dac, if you do not want to shell out too much then I would recommend this cable

 

[Anonymous]

Thanks for all the help. I'll try out some music on an AV amp and see if I enjoy it without a DAC.

If I don't how will the setup go? Would it be that I would connect the PC to the DAC with an optical cable and from there I connect the DAC to the AV amp with analogue red/white plugs?

 

[professorhat]

Ci4N:If I don't how will the setup go? Would it be that I would connect the PC to the DAC with an optical cable and from there I connect the DAC to the AV amp with analogue red/white plugs?

Yup, that's basically it. Some DACs also have a USB input so you can go straight from the PC via USB which bypasses the soundcard. Not 100% on what the benefits are there - in theory I can see why this might be better than optical (since there is no requirement for conversion to light for the optical route). Maybe someone else can provide a bit more detail on that.

But, yes, the DAC then connects into the AV amp via the red/white analogue phono leads.

 

[Alec]

Sorry, might be missing somthing, but has it not always been possible to connect pc to stereo amp with a phono to 3.5 jack?

Also, are'nt we close to implying that we need a dac if using an amp that doesnt have one, when in fact we dont? it can improve things, sure, but it isnt a necessity - PCs have them.

 

[professorhat]

al7478:Sorry, might be missing somthing, but has it not always been possible to connect pc to stereo amp with a phono to 3.5 jack?

Sure, if the PC has a 3.5mm output. If it doesn't, then no.

al7478:Also, are'nt we close to implying that we need a dac if using an amp that doesnt have one, when in fact we dont? it can improve things, sure, but it isnt a necessity - PCs have them.

I don't think so, but if that was implied, it wasn't meant. Unfortunately this thread got a bit confused with the introduction of stereo amps, so maybe it requires a "for clarification" post. Just about to eat me dinner so I might do this later on!

EDIT - I should note, I'm only blaming myself for that confusion having read through it again!