[Timestretch]

I would say that DACs to tend to sound the same. The differences in audio quality come along with all of the other components inside the box with the DAC -- power transformers, circuitry, capacitors, specific arrangement of parts, the analog output stage, etc. The DAC chips themselves by this point are pretty spot on. It's the stuff they fit in with that makes most of the difference.  
  
That said, does anyone have any reference for machine-measurements of the outputs of different dac chips? Just because we can't blind test a difference between chips doesn't mean there isn't a fraction of a percent difference in THD or whatever among them.
 
And about the noise you're experiencing -- interference, power, ground loops, etc. A lot of electricity moving around in side a computer, creates a lot of interference. this gives you a louder noise floor when you use sensitive headphones to listen for it. Perhaps by hooking the speakers in first, and then the headphones into them, you are adding resistance or something that is muting out that noisefloor a little more? I'm no electrician so someone who knows the exact reasons for this would need to chime in.
 
Quote:

 
This post was extremely informative. My understanding of this post is that all DAC's should be the same then? if they aren't converting the 1's and 0's into the correct analogue signal then the music would sound completely different? Does that mean the Cheap DAC's should cost the same as the expensive DAC's? Also what do you mean by quiet? Is this to stop sensitive headphones from hissing or hearing an electrical noise? When I connect my e10's to the line out of the PC mobo, I get electrical noise. Even when I connect the speakers to the mobo line out and then my e10's to the line out of the speaker, but the noise isn't as loud. Does this have anything to do with this topic?
 

 
 

 

 

[RayleighSilvers]

I am an electrician (well a trainee anyway 

) but we don't really cover microelectronics as much.

 

[Timestretch]

I'm just an office man, so to me, an electrician is basically an electric magician.
Quote:

I am an electrician (well a trainee anyway 

) but we don't really cover microelectronics as much.

 

 

[onlyjoekin]

I know what a DAC does, but I don't understand this-
People connect DACs after computers in their chain, but surely the signal is already in analogue from the built-in DAC? Does this mean stand alone DACs just improve the analogue signal or does the computer somehow cleverly detect it's there and not bother with it's own d-a conversion? I'm confused. And sorry to add this to an old thread, but ya know, better then starting a new one isn't it?

Joe

 

[skamp]

Your operating system has configuration facilities to tell your PC what DAC to use, the onboard one or the external one. So your external DAC is indeed only getting digital data, not analog data. The onboard DAC doesn't get used at all.

 

[onlyjoekin]

Ah, thanks for getting bak to me. You don't happen to know how to configure the DAC settings on mac OS X?

 

[skamp]

I don't know about Mac OS X, sorry.

 

[onlyjoekin]

Thanks a lot anyway!

 

[wberghofer]

You don't happen to know how to configure the DAC settings on mac OS X?

 
There’s nothing DAC specific which needs to be configured in Mac OS X. Just connect your DAC via USB or optical SPDIF (Toslink), visit System Preferences > Sound, choose the connection and you’re done. It might be useful to run Utilities > Audio MIDI Setup and check the sampling rate and bit depth for the selected audio output device. For standard CD audio playback the options should be set to 44100 Hertz and 2ch-16 bit Integer.
 
Werner.

 

[onlyjoekin]

Ah, thank you for this. I'm in danger of hijacking this thread, but what does the 'bit integer' mean? 'bits' are data aren't they, so does it mean how long the gap is between each bit sent? If you don't ask, you don't learn!
 
 
Joe

 

[skamp]

Look it up on Wikipedia: Pulse Code Modulation, bit depth, sampling rate.

 

[onlyjoekin]

Thanks again, I did try looking it up before posting but didn't really know what keywords to use. Makes for some technical reading!

 

[438518]

hi! i still cant understand! is it a music player? why do an amp need a DAC? i dont understand, ... if i connect an Headphone amp to my Laptop, who is the DAC does a PC have it, why an amp require a DAC when it is conected to 3.5 mm jack headphone output and amplifying in the other side, and the sound is perfect.

 

[ProtegeManiac]

Quote:

Originally Posted by Ujka Pjetracaj /img/forum/go_quote.gif

hi! i still cant understand! is it a music player? why do an amp need a DAC? i dont understand, ... if i connect an Headphone amp to my Laptop, who is the DAC does a PC have it, why an amp require a DAC when it is conected to 3.5 mm jack headphone output and amplifying in the other side, and the sound is perfect.

 

The laptop has a DAC but audiophile bull aside what you really need a separate DAC for isn't for the different DAC chip in it specifically but for the circuit after it. Once the signal leaves the DAC chip or the DA section of an integrated chip the analogue signal can take on noise or distortion depending on how it's handled. A separate DAC unit designed to output a fixed 2v output (which is Sony Redbook standard for CDPs) at the very least will take the guesswork out of what level to set anything, since that one is at a fixed level already, so all you have to worry about is your amplifier's volume and gain settings. By comparison your laptop's headphone output was designed to drive a headphone, and it may be too strong a signal for the amplifier, or have a lot of noise and maybe distortion that the amplifier can pick up and make even more audible, plus in older operating systems (not sure if it's still true in newer OS) the digital volume control can lower the bit depth (you'll go below 16bits). A dedicated DAC will take all the guesswork out of figuring out the best setting in terms of noise without affecting the bit depth

 

That said there are a couple of things to note here. There are DACs that output more than 2volts, best guess is that especially when it's not a lot over 2volts, it can have a significant edge in a subjective comparison. At the same time there are cases where the DAC's output stage can make a significant difference depending on how they implement the analogue stage, not necessarily as distortion per se (although that isn't out of the question, like how some deliberately color it with tubes) but sometimes the filter for the inaudible frequencies may affect the audible range differently.

 

[438518]

im far away to understand it, thank you anyway.