[Solitary1]

Man, USB is never going to be as good as SPDIF. This discussion came up on another forum. USB was intended for mice and keyboards. There are some decebt implementations of USB DACS out there, but the serious, high end stuff wouldn't even consider it.

 

[FallenAngel]

USB can definitely be MUCH better than S/PDIF can ever achieve, it's just not at that level yet.

 

[Solitary1]

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif USB can definitely be MUCH better than S/PDIF can ever achieve, it's just not at that level yet.

And you're basing that statement on.....

 

[anwaypasible]

receivers with DSP's see the digital audio stream at a higher resolution than a DAC.

DSP's are known for 2 things:
1. manipulating audio steams
2. taking the place of a DAC by using a giant eyeball with lots more resolution than a standard DAC in soundcards. (and this is because the DSP in the receiver has a much greater 'jitter' correction than a DAC running oversampled)

i've spoke about analog to digital convertors and x,y coordinates..
basically a DSP will recover more x,y coordinate mistakes than a oversampling DAC (simply because the industry has designed things that way.. MAINLY FOR AMATEUR DIRECTORS - hence amateur sound mastering on DVD)

enjoy

 

[Bredin]

Quote:

Originally Posted by Justin Uthadude /img/forum/go_quote.gif USB dacs supports asio and wasapi. This is an excellent read. Look at the bottom for all the other hifi gurus' responses.

That link didn't say ANYTHING.

 

[linuxworks]

Quote:

Originally Posted by Solitary1 /img/forum/go_quote.gif Man, USB is never going to be as good as SPDIF. This discussion came up on another forum. USB was intended for mice and keyboards. There are some decebt implementations of USB DACS out there, but the serious, high end stuff wouldn't even consider it.

interesting.

got data to support your wild assertions?

 

[linuxworks]

Quote:

Originally Posted by Solitary1 /img/forum/go_quote.gif And you're basing that statement on.....

in theory, usb is able to be better. why?

usb is a balanced protocol; meaning that each message can be ACKd. there is no 'back channel' in spdif, no acks, no checksums, no retries, no buffering. spdif is realtime only, and all the downsides of a non buffered protocol.

usb 2.0 can send data 'ahead' and be buffered locally and clocked out locally. even smart things like having a computer send timestamps down the wire for better replay clocking. spdif can't ever do that.

usb1.1 was meant for low speed devices but do you realize that spdif on redbook IS a 'slow device' ?

if usb2.0 ever gets used to its full potential (think emu 0404usb and similar) then it has quite an advantage over the non-acked realtime spdif limitations.

 

[linuxworks]

Quote:

Originally Posted by Kurotetsu /img/forum/go_quote.gif Optical isn't necessarily the best due to lack of error correction and, depending on the cable, can be quite lossy.

in my 20 or so years of doing spdif, I've never seen a bit error or 'loss' at spdif; not using coax or opto. it does not happen, in the real world.

Quote:

Coax takes second place due to having more durable and easier to come by cables. You can also run it for a much longer distances than optical, and you can curve it around obstacles without degrading anything.

the bend radius is something to worry about on opto, its true.

but actually, I'd prefer opto for longer runs. and its not hard to adjust the 'gain' on the toslink sending side (or just repeat the signal with an active repeater) so that there's enough light to get to the other side and reconstruct the waves.

Quote:

Optical's biggest advantage, compared to coax, is that it has an 'always on' signal.

and coax isn't??? that's quite wrong. all spdif is 'always on' in terms of an idling signal or 'carrier' (loose term).

Quote:

Some DACs or receivers open or close their digital connection depending whether a signal is being received or not (this is usually heard as a 'click' or something when you computer turns on, for example).

this is muting, and has nothing to do with what you are talking about.

muting can happen in various ways (detection of 'too many zeroes' or invalid spdif).

Quote:

With coax, you could possibly be hearing clicking more often as the connection opens and closes due to the presence or absence of a signal. Since optical is always on, this isn't an issue.

you are wrong.

 

[joe_cool]

Quote:

Originally Posted by Bredin /img/forum/go_quote.gif That link didn't say ANYTHING.

I agree, but Steve Nugent and Gordon Rankin had some REAL interesting viewpoints.

 

[Budley007]

I don't think there is an absolute answer to this "right now". For years S/PDIF was the definitive interface for digital audio. Some say BNC is the absolute best iteration, hands down, followed by coax then toslink. The music industry still prefers firewire. And computer audio enthusiast would love for USB to be better than it already is. It's not.

For convenience alone, I'd pick USB, but it's not the best...yet.

 

[linuxworks]

Quote:

Originally Posted by Budley007 /img/forum/go_quote.gif Some say BNC is the absolute best iteration, hands down, followed by coax then toslink.

bnc IS coax. loosely speaking.

spdif was designed, from the very beginning, to use existing video cabling and video infrastruture (75ohm cable).

the connector just does not matter in the real world. I've run spdif over Really Bad(tm) things and it works just fine.

how many dacs and spdif transmitters are TRUE to 75ohms, end to end, pc traces and all? probably none.

it simply does not matter.

 

[ericj]

Quote:

Originally Posted by anwaypasible /img/forum/go_quote.gif receivers with DSP's see the digital audio stream at a higher resolution than a DAC.

That's the funniest thing I've read on head-fi in months.

Admittedly i stay out of patrick's threads, but still.

 

[ericj]

Honestly, a DSP is a digital signal processor. It does whatever it's programmed to do. It can do it well or poorly, depending on the code and how well the dsp is designed for the task it's been programmed to do.

Some of them are software programmable and some of them are fixed-purpose.

Most modern DAC hardware includes some fixed-purpose DSP functionality built right into the DAC chip.

A small number of DSP chips have built-in DAC functionality, but to say that a DSP replaces a DAC is to completely misunderstand what these parts do.

 

[ROBSCIX]

Quote:

Originally Posted by anwaypasible /img/forum/go_quote.gif receivers with DSP's see the digital audio stream at a higher resolution than a DAC. DSP's are known for 2 things: 1. manipulating audio steams 2. taking the place of a DAC by using a giant eyeball with lots more resolution than a standard DAC in soundcards. (and this is because the DSP in the receiver has a much greater 'jitter' correction than a DAC running oversampled) i've spoke about analog to digital convertors and x,y coordinates.. basically a DSP will recover more x,y coordinate mistakes than a oversampling DAC (simply because the industry has designed things that way.. MAINLY FOR AMATEUR DIRECTORS - hence amateur sound mastering on DVD) enjoy

There is a digital audio primer around. I suggest you start there.

 

[keezzzz]

On my Macbook Optical , On the Acer Laptop USB