Jitter in firewire/USB connection?

[bigshot]

Quote:

Originally Posted by DefectiveAudioComponent /img/forum/go_quote.gif If it is not audible then I suppose that many engineers would not bother with re-clocking...

Pro audio is a different animal than home audio. The requirements of mixing are different than the needs of just listening to music. For home audio "the hard way" is also the way with more opportunity for healthy profit markups. The fact that jitter is inaudible is irrelevant when compared to the bottom line. It's hard to differentiate yourself as a manufacturer, and charge three or four times as much as your competition unless you justify that with some sort of explanation.

The truth is, even very low cost equipment- the sort that audiophiles scoff at- performs audibly as well when it comes to jitter as the most expensive and exclusive high end equipment. No one should waste their time worrying about jitter, unless they under the employ of an equipment manufacturer looking for something convincing sounding to print in their sales literature.

Now this thread will go through another cycle of very technical and confusing back and forth just to come back around to the same conclusion- jitter doesn't matter. I'm beginning to think obfuscation is the goal, not providing useful advice to help people efficiently create great sounding systems.

See ya
Steve

 

[LnxPrgr3]

Quote:

Originally Posted by DefectiveAudioComponent /img/forum/go_quote.gif If it is not audible then I suppose that many engineers would not bother with re-clocking...

They already have to -- the difference is, they're staying in step with the SOF timing. It's still not at the right rate to drive a DAC at any normal samplerate.

Either way, as bigshot said, there's motivation to do things that are technically pointless just to help market the device. Why does Creative sell 24-bit cards to people playing games and listening to mp3s and CDs?

 

[devilsound]

Quote:

Originally Posted by thomaspf /img/forum/go_quote.gif Stereophile has measured DACs <$1K dac at 120ps. The low jitter part does not need to break the bank and you can concentrate on the many other factors that might have more impact on the sound. Low jitter and price is not necessarily coupled. Cheers Thomas

Agreed. The chips themselves do not actually cost that much at all; the money goes to the design of the circuit, which gets passed on to the price of the DAC, since most high-end audio is fairly low volume.

But at this point, jitter and re-clocking circuits are fairly well understood, and making a solid DAC in general is getting to be sort of an open secret. So the price of good audio is coming down, at the same time the quality is increasing ...

Jonathan
devilsound labs

 

[thomaspf]

Quote:

Originally Posted by LnxPrgr3 /img/forum/go_quote.gif This makes me wonder why more devices don't use the DAC's clock as the master, which the USB audio standard allows. Audible or not, it would make jitter in the SOF timing a non-issue. Seems like it would be technically easier too, but not having designed a USB DAC, I can't comment too in depth

That is exactly the USB audio async mode that was mentioned earlier. Gordon sells DACs using that strategy.

Cheers


Thomas

 

[thomaspf]

Quote:

Originally Posted by bigshot /img/forum/go_quote.gif Now this thread will go through another cycle of very technical and confusing back and forth just to come back around to the same conclusion- jitter doesn't matter. I'm beginning to think obfuscation is the goal, not providing useful advice to help people efficiently create great sounding systems. See ya Steve

So please enlighten us. What are the factors that do matter and how can I detect those?

Cheers

Thomas

 

[bigshot]

In a nutshell... The things that make a big difference are transducers, room acoustics, proper equalization, ease of use, and well mixed recordings calibrated to be played flat and not hot mastered.

The things that don't matter nearly as much are formats (vinyl vs CD), quality of electronic components, and lossy encoding (as long as the bitrate is high enough).

The things that either matter or they don't are shielding and power conditioning. (And they usually don't.)

The things that don't matter at all include jitter, SACD, high bitrate playback, specs beyond the range of human hearing and fancy wires.

It's ironic that a lot of effort is expended discussing the bottom items on this list, and not as much on the ones at the top.

See ya
Steve

 

[thomaspf]

I think I hinted to the reason in an earlier post.

If you want a significant upgrade in your audio system look at the speakers but there you quickly get into real money and the religious factions are even more dogmatic.

Jitter is a relatively cheap and measurable topic to argue about.

Cheers

Thomas

 

[bigshot]

Jitter may be cheap and measurable, but it's also inaudible. There really isn't much to argue about. It isn't an issue.

See ya
Steve

 

[thomaspf]

What would you look for in a digital source to get the best sound?

Just for personal interest. What speakers do you use in your system? I am using Harbeth Monitor 40.

Cheers

Thomas

 

[bigshot]

To be honest, to get the best sound from a digital source, I would choose a well mixed and mastered recording to play on it. There are plenty of inexpensive CD players (and DAPs) capable of producing great sound quality. It's hard *not* to get a good sounding CD player.

My speakers were custom made for me by a friend of my brother's who built speakers for JBL and Rogers Sound Labs. I've had them since the late 70s. I've also got some JBLs and bookshelf speakers that I don't remember the brand of offhand that I use for my surrounds in my AV system.

See ya
Steve

 

[thomaspf]

I agree, I have not been able to discern differences from any digital source driving my Lavry DA10.

Do you use any form of room treatment and equalization?

Cheers

Thomas

 

[bigshot]

In my cramped space, room treatment is a lost cause I'm afraid. I've raised my speakers to ear level and cleared out the space around them. That's all I can do for now. When I move, things will be a lot better. I use a Rane DEQ60 dual 31 band equalizer to get things as flat as humanly possible. That's the piece of audio equipment that has had the biggest impact on sound quality in my system. I wouldn't be without it.

See ya
Steve