DIYHiFi.org

For the sake of audio
It is currently Thu May 23, 2013 10:39 am

All times are UTC




Post new topic Reply to topic  [ 100 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6, 7  Next
Author Message
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Tue Apr 26, 2011 5:58 am 
Offline

Joined: Mon Sep 26, 2005 4:09 am
Posts: 342
If you see that much CPU utilization it's abnormal even considering USB is 100% host-controlled (polled). Maybe not if your CPU is an Atom or something.

It can also depend on the USB host controller and driver used. I haven't had anything but good experiences with the Intel host controllers integrated into ICH8, ICH9, and ICH10.

You were transcoding as well, Carlos? Probably the codec eating CPU time.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Tue Apr 26, 2011 6:16 pm 
Offline

Joined: Fri Nov 04, 2005 4:10 pm
Posts: 563
Location: uk
Charles Hansen wrote:
fmak wrote:
What I said was that variability in sound and voicing with async usb is as much, if not more, in usb connections than good spdif ones. This, to my ears, clouds any advantages of the claim of superior performance.


Why???

How do you know that the reason USB is sensitive to cables is not because it passes more information than S/PDIF?


If what you say is true, then sensitivity to cables become a subject of its own in relation to bit perefection being imperfect..

You said here that you had no interest in why this should be the case.

I am interested, hence my reaction to posts claiming that this is the 'one brain' interface for computer audio and that others are 'broken', whatever broken means.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Tue Apr 26, 2011 6:53 pm 
Offline
User avatar

Joined: Tue Dec 14, 2004 12:26 pm
Posts: 4652
Location: Lisbon, Portugal
chris719 wrote:
You were transcoding as well, Carlos? Probably the codec eating CPU time.


Exactly, I transcode the audio codecs that my TV doesn't support (including FLAC).
I was ironic in saying the CPU was at 15% when decoding 24/192 flac to WAV and sending through the network to the TV. It is obviously a low CPU usage for such an old, single core PIII machine.
Sending a 1080p Full HD video through the network to the TV (no transcoding), the CPU usage is very low (less than 5%) and the network usage is between 10 to 15%.
A good network card (which doesn't take much CPU, like my Intel PRO/1000) even when working at 100Mb/s, is enough for all this, even on an old machine.

I find it strange that some say USB(2) does not handle 24/192 very well, it should handle it without glitches, specially on a modern machine - even an Atom CPU...

_________________
Carlos Filipe

"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction." Albert Einstein


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Tue Apr 26, 2011 6:59 pm 
Offline
User avatar

Joined: Tue Dec 14, 2004 12:26 pm
Posts: 4652
Location: Lisbon, Portugal
Charles Hansen wrote:
carlosfm wrote:
My question is, why does USB have problems with 192Khz?
foobar transcoding 24/192 flac to 24/192 WAV and sending through the network puts this old machine at an astonishing 15% CPU utilization.
What's the problem with USB, then?


What makes you think USB has any problems with 192 kHz?

You gave zero evidence of any kind that USB has problems with 192 kHz. So why even ask the question?


Charles, read my post again. Read my last post too, above this one.
I don't think USB has problems at 24/192.
My question was for those who say it does.

_________________
Carlos Filipe

"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction." Albert Einstein


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Wed Apr 27, 2011 1:45 am 
Offline
User avatar

Joined: Mon Dec 13, 2004 2:32 pm
Posts: 1318
Carlos, the problem can manifest as anything you can imagine here, glitches and total loss of audiostream included.

But then again, I think it is now safe to say that these problems are past. And no, this past wasn't that long ago.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Wed Apr 27, 2011 6:05 am 
Offline

Joined: Fri Nov 04, 2005 4:10 pm
Posts: 563
Location: uk
Pedja wrote:
Carlos, the problem can manifest as anything you can imagine here, glitches and total loss of audiostream included.

But then again, I think it is now safe to say that these problems are past. And no, this past wasn't that long ago.


Carlos,

Don't use a server arrangement. Put everything on your PC, surf while you listen, paste a web page using Word, and see if your experience anything. This is how I gauge interface robustness.

Oh, don't use a large-eee buffer to avoid it, as this changes SQ adversely.

There is an eye catching series of shots here:

http://www.aqvox.de/usb-power_en.html

Cut your V+ on your usb cable for a unit not requiring bus power (or supply your own 5V) and see if you hear a difference. On a good system, this can have a MAJOR effect. This is why I said what I said.

Oh, run Prime 95 as well.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Wed Apr 27, 2011 6:07 am 
Offline

Joined: Fri Nov 04, 2005 4:10 pm
Posts: 563
Location: uk
chris719 wrote:
If you see that much CPU utilization it's abnormal even considering USB is 100% host-controlled (polled). Maybe not if your CPU is an Atom or something.

It can also depend on the USB host controller and driver used. I haven't had anything but good experiences with the Intel host controllers integrated into ICH8, ICH9, and ICH10.

You were transcoding as well, Carlos? Probably the codec eating CPU time.


You said I posted crap. What is this? You hadn't even understood his post.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Wed Apr 27, 2011 8:59 am 
Offline
User avatar

Joined: Tue Dec 14, 2004 12:26 pm
Posts: 4652
Location: Lisbon, Portugal
fmak wrote:
Carlos,

Don't use a server arrangement. Put everything on your PC, surf while you listen, paste a web page using Word, and see if your experience anything. This is how I gauge interface robustness.


Indeed, surfing the internet is not that "light" these days.
Many pages are "heavy", too much javascript.
Watching a video on youtube, with that Flash bloatware, is very CPU intensive, unless you have good, recent video card with mp4 hardware decoding.

Btw, when I want to save a web page, I save as a single .mht file. Why use Word?
Off-topic: Office 2010 is much faster and lighter than previous versions (2007, 2003, etc.).
IE9 is much faster than any previous version.
I think that Microsoft is improving, since Bill has retired. (!)

_________________
Carlos Filipe

"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction." Albert Einstein


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Wed Apr 27, 2011 11:00 am 
Offline

Joined: Fri Nov 04, 2005 4:10 pm
Posts: 563
Location: uk
I save as a single .mht file. Why use Word?
Off-topic: Office 2010 is much faster and lighter than previous versions (2007, 2003, etc.).
IE9 is much faster than any previous version.
---------------------------------------------------------------

Use Word when I want to archive on a topic after editing the text. PDF makers don't always work or scale correctly

Office 2010 is aweful, full of icons that make me dissy. I prefer Word 2000 - slightly slower than 2010 but simple to view and lighter weight. All these secretarial features are useless to me.

I uninstalled IE9 'cause it just tries to copy some Safari features. The Icons are too small and I prefer IE8.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Fri Apr 29, 2011 6:48 am 
Offline
User avatar

Joined: Thu Jul 26, 2007 5:45 pm
Posts: 437
Hi,

carlosfm wrote:
My question is, why does USB have problems with 192Khz?


It is my experience that USB does not have as such problems with 192/24.

Various solutions (we tried pretty much all of them as per 1/2 year ago) all can stream audio reliably with nothing better than a P42.8GHz (the lowest desktops we have), Pentium Mobile 1.7G Laptop and some description of Macbooks running Snowleopard.

PM1.7 and Atom 270 do have some issues when playing Hi-Rez while browsing through albums in heavily graphically intensive frontends, but pure, playing only, zero issues.

Of course, one has to check that there no rouge drivers causing high latency, but if this is the case not only USB playback suffers. So I really do not see why USB especially should have problems, in PC playback over other methods.

Getting Bitperfect High Resolution on PC or MAC is quite easy now, but it still takes some work. I suspect the "problem with USB is simply that people wrongly assume it is "plug and play".

I had a USB Dac of mine with a reviewer, who said it sounded okay, but nothing special next to his CD Player. Turns out he had just plugged it into a generic windows machine and was using windows media player in default setup to rip (to MP3 of course) and play back, plus he complained downloaded "High Rez" track where not working (no Flac Playback on WMP of course) probably the DAC was no High Rez as I claimed...

Once I told him how to correctly set things up things changed radically and it was only installing and correctly setting up JRMC, which is normally a 10 Minutes affair, but he simply had not even considered such stuff necessary. While clearly feeling a little sheepish he quipped: "But isn't USB supposed to be plug'n'play.", I thought modern computers where build for multimedia?"

I suspect that most of the problems ascribed to "USB" are simply people setting up their Audio PC & DAC with about as much care as they take plugging in a mouse, if that much...

Ciao T

_________________
Theory is when you know everything but nothing works.
Practice is when everything works but you don't know why.
Guruhood is when you know everything and everything works accordingly.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Fri Apr 29, 2011 7:23 am 
Offline

Joined: Fri Nov 04, 2005 4:10 pm
Posts: 563
Location: uk
Kuei Yang Wang wrote:

I suspect that most of the problems ascribed to "USB" are simply people setting up their Audio PC & DAC with about as much care as they take plugging in a mouse, if that much...

Ciao T


I set up my stuff with great care.

But you have hit it on the nail, usb audio is not universal and it is better to have drivers that set things up correctly.

I peronally DO not like JRM, why all this video and bloated stuff for audio.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Fri Apr 29, 2011 8:55 am 
Offline
User avatar

Joined: Tue Dec 14, 2004 12:26 pm
Posts: 4652
Location: Lisbon, Portugal
Kuei Yang Wang wrote:
I had a USB Dac of mine with a reviewer, who said it sounded okay, but nothing special next to his CD Player. Turns out he had just plugged it into a generic windows machine and was using windows media player in default setup to rip (to MP3 of course) and play back, plus he complained downloaded "High Rez" track where not working (no Flac Playback on WMP of course) probably the DAC was no High Rez as I claimed...


What kind of reviewer was that, from some PC magazine? :doh:

_________________
Carlos Filipe

"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction." Albert Einstein


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Sat Apr 30, 2011 12:20 am 
Offline

Joined: Fri Apr 17, 2009 6:41 am
Posts: 9
HiFace Evo is missing from the comparison.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Sun May 01, 2011 4:46 am 
Offline
User avatar

Joined: Thu Jul 26, 2007 5:45 pm
Posts: 437
Hi,

fmak wrote:
I peronally DO not like JRM, why all this video and bloated stuff for audio.


Well, for JR to have a sellable product that people will pay money for it has to be there.

No need to use the video features though.

In terms of audio quality with a user interface that is is not the equivalent of wearing it hairshirt and easy setup it stands alone in my experience...

Ciao T

PS, the reviewer was an audio guy, but with zero experience and exposure to high quality audio vai PC, so basically the same as your average audiophile. It was not really his fault for having wrong expectations, it was his fault for RTFM though...

_________________
Theory is when you know everything but nothing works.
Practice is when everything works but you don't know why.
Guruhood is when you know everything and everything works accordingly.


Top
 Profile  
 
 Post subject: Re: Jitter Free SPDIF?
PostPosted: Mon May 30, 2011 4:23 pm 
Offline

Joined: Fri Nov 04, 2005 4:10 pm
Posts: 563
Location: uk
gmarsh wrote:

This is I have a XMOS evaluation board on my desk, 3 feet from me, which disagrees with you. I've had 24/192 asynchronous audio running reliably under both Windows 7 and Linux, and I've never heard a dropout.

Hell, I'll make the board flag a buffer underflow, put some 24/192 FLAC on loop and start up Prime95 to drive the computer to 100% CPU usage for a few hours, just to prove you wrong.

There's nothing stopping me from putting a PCI USB card in a 486SX/16 with 8 megs of RAM and attempting to make 24/192 USB audio work on it - sure enough, it probably won't work. Does that mean the whole USB interface is flawed? hell no. If your computer, USB drivers and whatnot can't keep up with a 24/192 USB audio interface, that's not USB's fault - it means your computer is either inadequate for the job, or there's something wrong with your computer's configuration.

And that's the facts. There's nothing here for me to "bury my head in the sand" to avoid. You stated, specifically, "usb audio doesn't work reliably at high rates", but in my experience, it does.


I have just come across this:

<USB audio streaming corrupted by high DPC latency spikes in Windows 7 64-bit. Is anyone on this?

I have access to four computers (two Dells, two I built myself from high quality components), and on three of them I have trouble with outboard USB audio streaming under Windows 7, which is corrupted by pops and clicks accompanying high DPC latency spikes. The machines all play sound properly from their native sound cards.

I have been using two outboard USB DACs -- a Headroom Desktop Ultra DAC and a Musicstreamer+. On a Dell XPS 420 running Windows 7, I get pops and clicks. On an AMD Phenom II 965BE system I built on an Asus EVO mobo with 8gb of DDR3 memory, I get clean sound. On an Intel i7-930 system I built on an Asus mobo with 6 gb of DDR3 memory, I get pops and clicks. On a Dell Latitude E6500 laptop with a dual core Intel processor and 4 gb of DDR2 memory, I get pops and clicks.

I used high quality power supplies (e.g., Seasonic X650) and other similar components in the systems I built. I have spent hours updating drivers, disabling devices, modifying settings (including wifi, etc.), and other troubleshooting without being able to reduce or eliminate the problem. I never had this problem when I was running Windows XP.

Given the rash of complaints I have found across the internet about DPC latency spiking interfering with onboard and outboard audio under Windows 7, I'm left to conclude that it is a Windows 7 kernal problem.

Is Microsoft working on this issue at the OS level? It seems there is a fundamental problem in Windows 7 that makes it a terrible choice for people looking for a high grade music server for audiophile applications.
February 6, 2011>

Link:
http://answers.microsoft.com/en-us/wind ... d5fbde55d6

Burying head in sand means not listening to issues. This is how products fail in the market place.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 100 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6, 7  Next

All times are UTC


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group