Will my new PC to PC setup work for Jack 2?

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Will my new PC to PC setup work for Jack 2?

Bearcat M. Şándor
Folks,

I'm running jack 1.9.5 on a q9300 with 8 gigs of ram. I want better D/A
conversion than what i have now (an intel hd on-board chip) and i have a
plan to accomplish that. I'm wondering what limitations i'll face and
whether it will work at all.

What i'd like to do is to get a small-form, headless computer. Like an
atom 1.6 ghz with 4 gigs of ram in it.  What i'll do is to do all of the
processing (ambisonics, upsampling, video playing etc) on my quad core.
Then send that stream over to the atom computer via net jack though an
ethernet cable that is hooked directly between the them (no router or
other network interference.  Once in the atom computer the sound will be
out put through a Asus xonar essence ST soundcard. All this atom will be
is a transport (a D/A).

Are there any problems with this idea? Will the jack instances on each
computer be able to synch up or will i get drift (especially when
watching video on the quad core)?

How much computing headroom would i have on this atom computer once jack
is handling 24/192 (up to 8 channels)?  If i migrate my mail server to
the atom computer and hook it into the network (the jack server
connection would be on it's own ethernet port so no network congestion
should occur there) will that screw things up?

I'm running a full desktop on this quadcore with a mail server, web
server etc and i get occasional drop-outs from jack. I may have to move
all that to a 3rd pc.

Thanks folks.

Bearcat M. Sandor


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Re: Will my new PC to PC setup work for Jack 2?

Jörn Nettingsmeier-5
On 04/21/2010 09:24 AM, Bearcat M. Şandor wrote:

> Folks,
>
> I'm running jack 1.9.5 on a q9300 with 8 gigs of ram. I want better D/A
> conversion than what i have now (an intel hd on-board chip) and i have a
> plan to accomplish that. I'm wondering what limitations i'll face and
> whether it will work at all.
>
> What i'd like to do is to get a small-form, headless computer. Like an
> atom 1.6 ghz with 4 gigs of ram in it.  What i'll do is to do all of the
> processing (ambisonics, upsampling, video playing etc) on my quad core.
> Then send that stream over to the atom computer via net jack though an
> ethernet cable that is hooked directly between the them (no router or
> other network interference.  Once in the atom computer the sound will be
> out put through a Asus xonar essence ST soundcard. All this atom will be
> is a transport (a D/A).

not sure i understand... why don't you just put a better soundcard into
your quad box?

> Are there any problems with this idea? Will the jack instances on each
> computer be able to synch up or will i get drift (especially when
> watching video on the quad core)?

the atom machine (the one with the soundcard) will provide the clock.
the quad will be slaved to it.

> How much computing headroom would i have on this atom computer once jack
> is handling 24/192 (up to 8 channels)?

ditch that 192k, it's rubbish. go for 48k, that's plenty. the cpu
headroom on the atom will depend on the network buffer size a lot. but
the way i see it, you don't need very low latency.

but still, i don't really see the point of the whole exercise...


--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487

Meister für Veranstaltungstechnik (Bühne/Studio), Elektrofachkraft
Audio and event engineer - Ambisonic surround recordings

http://stackingdwarves.net

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Re: Will my new PC to PC setup work for Jack 2?

Ralf Mardorf
In reply to this post by Bearcat M. Şándor

> I'm running a full desktop on this quadcore with a mail server, web
> server etc and i get occasional drop-outs from jack.

Hi :)

sounds like your sound card is an expensive, even so consumer sound
card. Did you try to increase Periods/Buffer? What kernel do you use?

Cheers!
Ralf
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Re: Will my new PC to PC setup work for Jack 2?

Ralf Mardorf
In reply to this post by Jörn Nettingsmeier-5
Jörn Nettingsmeier wrote:

> On 04/21/2010 09:24 AM, Bearcat M. Şandor wrote:
>  
>> Folks,
>>
>> I'm running jack 1.9.5 on a q9300 with 8 gigs of ram. I want better D/A
>> conversion than what i have now (an intel hd on-board chip) and i have a
>> plan to accomplish that. I'm wondering what limitations i'll face and
>> whether it will work at all.
>>
>> What i'd like to do is to get a small-form, headless computer. Like an
>> atom 1.6 ghz with 4 gigs of ram in it.  What i'll do is to do all of the
>> processing (ambisonics, upsampling, video playing etc) on my quad core.
>> Then send that stream over to the atom computer via net jack though an
>> ethernet cable that is hooked directly between the them (no router or
>> other network interference.  Once in the atom computer the sound will be
>> out put through a Asus xonar essence ST soundcard. All this atom will be
>> is a transport (a D/A).
>>    
>
> not sure i understand... why don't you just put a better soundcard into
> your quad box?
>  

Oops, now I see it's currently a intel hd on-board chip, so you should
definitive use 3 Periods/Buffer instead of 2.

>> Are there any problems with this idea? Will the jack instances on each
>> computer be able to synch up or will i get drift (especially when
>> watching video on the quad core)?
>>    
>
> the atom machine (the one with the soundcard) will provide the clock.
> the quad will be slaved to it.
>
>  
>> How much computing headroom would i have on this atom computer once jack
>> is handling 24/192 (up to 8 channels)?
>>    
>
> ditch that 192k, it's rubbish. go for 48k, that's plenty.

I disagree, but I guess 96 KHz should be enough.

>  the cpu
> headroom on the atom will depend on the network buffer size a lot. but
> the way i see it, you don't need very low latency.
>
> but still, i don't really see the point of the whole exercise...
>  
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Re: Will my new PC to PC setup work for Jack 2?

Fons Adriaensen-2
In reply to this post by Jörn Nettingsmeier-5
On Wed, Apr 21, 2010 at 09:50:45AM +0200, Jörn Nettingsmeier wrote:

> On 04/21/2010 09:24 AM, Bearcat M. Şandor wrote:
> >
> > What i'd like to do is to get a small-form, headless computer. Like an
> > atom 1.6 ghz with 4 gigs of ram in it.  What i'll do is to do all of the
> > processing (ambisonics, upsampling, video playing etc) on my quad core.
> > Then send that stream over to the atom computer via net jack though an
> > ethernet cable that is hooked directly between the them (no router or
> > other network interference.  Once in the atom computer the sound will be
> > out put through a Asus xonar essence ST soundcard. All this atom will be
> > is a transport (a D/A).
>
> ...
>
> but still, i don't really see the point of the whole exercise...

Neither do I. A good soundcard in the main machine, running at
48 kHz, will do the trick. What's the point of the upsampling ?
Your sound card will do that before conversion. Unless you buy
really crap HW it will be done as accurately as any softare
implementation, maybe even better.

And in fact, DA conversion is equivalent to upsampling to
an 'infinite' sample frequency.

Ciao,

--
FA

O tu, che porte, correndo si ?
E guerra e morte !
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Re: Will my new PC to PC setup work for Jack 2?

Ed Wildgoose-2
In reply to this post by Bearcat M. Şándor
On 21/04/2010 08:24, Bearcat M. Şandor wrote:

> Folks,
>
> I'm running jack 1.9.5 on a q9300 with 8 gigs of ram. I want better D/A
> conversion than what i have now (an intel hd on-board chip) and i have a
> plan to accomplish that. I'm wondering what limitations i'll face and
> whether it will work at all.
>
> What i'd like to do is to get a small-form, headless computer. Like an
> atom 1.6 ghz with 4 gigs of ram in it.  What i'll do is to do all of the
> processing (ambisonics, upsampling, video playing etc) on my quad core.
> Then send that stream over to the atom computer via net jack though an
> ethernet cable that is hooked directly between the them (no router or
> other network interference.  Once in the atom computer the sound will be
> out put through a Asus xonar essence ST soundcard. All this atom will be
> is a transport (a D/A).
>    

Funnily enough this is something that I am considering also, however,
for different reasons. Firstly I think your best chance of success is to
keep the quad box - my reason for looking at a dual box is that I want a
completely silent fanless system and I have tried various designs and
spent countless amounts of money over the years and unfortunately really
struggled to achieve this. The problem I have always faced is that the
machines run hot and typically they have always failed after 12-24
months (in various ways). It's a long story, but the two box solution I
would pick is really going to need to become a three box solution
including some ffado firewire audio card and it's all looking fairly
complicated right now...

Back to basics - what audio program are you using to supply audio to the
card? Quite likely your dropouts can be fixed here? Also you can
increase your period size on the card, this usually decreases CPU load,
plus setting appropriate realtime priorities on the correct tasks and
generally a modern kernel can meet very low scheduling latencies (most
of the time). I doubt your mailserver is doing more than idling and will
almost certainly be inconsequential?

I'm guessing you probably have brutefir involved and there is a big
tradeoff here based on fragment size vs cpu. Also upsampling to 192Khz
is of dubious benefit and if this is done badly it will cost you a lot
of audio quality, if it's done well it will absorb a HUGE amount of
CPU... (I use libsamplerate to downsample from 48Khz to 44Khz and the
quality is excellent, but it sucks CPU and I would dearly love to figure
some practical way to alter the sample rate in Jack, possibly in
conjunction with the autostart feature? Could I have two configurations
and find some way to select the correct one to start?)

Also see my previous enlightenment - the docs on the "-t" option are
misleading (it actually defaults to a much shorter time than stated) and
you should probably use flag that as part of your jack commandline so
that worst case your audio will continue in the event of some minor xrun
condition?

I believe most newer "HD" audio cards actually are of pretty reasonable
quality these days? Check the rightmark results for a basic guide. Lots
of people will get excited about super quality DACs and I'm also guilty
of coveting such things, but in practice I *personally* believe you will
need a mega expensive audio setup before the DAC becomes your limiting
factor...

Show your config in some detail if you need more

Good luck

Ed W

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Re: Will my new PC to PC setup work for Jack 2?

Ralf Mardorf
Ed W wrote: [snip]

Usually I do agree that 48 KHz are all that's needed, but the strange
thing I experienced is that for my cheap Envy24 based card, that
seemingly hasn't got the best converters and additional not the best
op-ams 96 KHz do safe sound quality, whatever the reason for this might
be, but this isn't why I do reply again.

It comes to my mind that "occasional drop-outs from jack" could be
caused by CPU frequency scaling, switching to "Performance" could solve
this issue.
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Re: Will my new PC to PC setup work for Jack 2?

Ed Wildgoose-2
On 21/04/2010 13:37, Ralf Mardorf wrote:
> Ed W wrote: [snip]
>
> Usually I do agree that 48 KHz are all that's needed, but the strange
> thing I experienced is that for my cheap Envy24 based card, that
> seemingly hasn't got the best converters and additional not the best
> op-ams 96 KHz do safe sound quality, whatever the reason for this
> might be, but this isn't why I do reply again.

I believe it's safe to assume that most DAC's, especially cheaper DACs
will work better at one freq than another.  However, I would be
surprised if this were generally audible in most reasonable quality
designs? (eg the old AC3 codec which resampled everything to 48Khz
internally using some really, really horrible resampler...)

I should check your whole audio chain for other problems that could
explain this, eg something resampling without you knowing it?

Oh, also note that a lot of "music" is released at 44.1Khz, therefore
you want even multiples of that for preference, eg 44.1/88.2/176.4Khz.  
The 48/96/192 is more appropriate for DVD audio.  You will burn a lot of
CPU doing high quality resampling from one class to another... (hint
find the lowest common denominator of 48 & 44.1)

> It comes to my mind that "occasional drop-outs from jack" could be
> caused by CPU frequency scaling, switching to "Performance" could
> solve this issue.

Why even guess this kind of thing rather than just measuring?

Temporarily turn off cpu scaling or at least watch top?  However, it's
simple enough to drop the cpu scaling threshold - I use something like
this at startup:
     echo 20 > /sys/devices/system/cpu/cpu0/cpufreq/ondemand/up_threshold
     echo 20 > /sys/devices/system/cpu/cpu1/cpufreq/ondemand/up_threshold

Cheers

Ed W
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Re: Will my new PC to PC setup work for Jack 2?

Fons Adriaensen-2
On Wed, Apr 21, 2010 at 03:04:20PM +0100, Ed W wrote:

> Oh, also note that a lot of "music" is released at 44.1Khz,
> therefore you want even multiples of that for preference, eg
> 44.1/88.2/176.4Khz.

Why ? There is no advantage in integer resample ratios.
Not for quality and almost nothing for required CPU.
Only some very simplistic (and not so good sounding)
algorithms get simpler for integer ratios.

> You will burn a lot of CPU doing high quality resampling

5.2% CPU for stereo, 21% for 8 channels on my 2G P4 (seven
years old now), on more recent boxes it's below 2% for stereo.
Zita-resampler at highest quality (which is a waste).

> from one class to another... (hint find the lowest common
> denominator of 48 & 44.1)

The LCM is irrelevant for both time complexity and quality.
 
Ciao,

--
FA

O tu, che porte, correndo si ?
E guerra e morte !
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Re: Will my new PC to PC setup work for Jack 2?

Bearcat M. Şándor
In reply to this post by Jörn Nettingsmeier-5
On Wed, 2010-04-21 at 09:50 +0200, Jörn Nettingsmeier wrote:

> not sure i understand... why don't you just put a better soundcard into
> your quad box?
I have experienced the difference between running an audio component off of AC power from the wall
and battery power.  I'm looking at the Atom to be able to run it off of batteries for long periods. The entire
Atom system will use less than my cpu does in my quad box.

> the atom machine (the one with the soundcard) will provide the clock.
> the quad will be slaved to it.
I've looked at the wiki and read through something about net jack, but i admit i missed that. So, if i'm
playing a video on the quad box and sending the audio stream to the
Atom, how does the Atom know about the video position to be able to
sync. If i'm playing music via mplayer or mpd on the quad how does the
atom computer know how to sync with it?  (i think i'm missing a vital
part of this understanding.)

> ditch that 192k, it's rubbish. go for 48k, that's plenty. the cpu
> headroom on the atom will depend on the network buffer size a lot. but
> the way i see it, you don't need very low latency.
You know i tend to agree about the 192k. I do find that 24-bit vs 16-bit makes a
big difference though.  Be that as it may, i do have lot of music in 96k.  So, the Atom (or whatever side)
needs to be able to handle that. If i watch a bluray, it would still
need the work of downgrading it to 48 khz, so what ever rate i set
things at there is going to be some up/down sampling at some point.
I'm glad i don't need a lot of lantency for this.
> but still, i don't really see the point of the whole exercise...
To run the D/A and my amps off batteries. <an_aside>I have a Trends Audio 10.1 amplifier which is run from DC power which
feeds a pair of Anthony Gallo Acoustics Reference 3.1s. Not the most
efficient things at 89db or so, but not too bad considering the
electrostatic-like tweeter. I tend to like smaller rooms so the 8-10
watts is plenty loud. I might upgrade to a Virtue Amp (also DC) for some
more grip on the system though,</an_aside>

Thanks for helping me figure this all out folks. Glad i didn't buy this Atom system just yet.

Bearcat

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Re: Will my new PC to PC setup work for Jack 2?

Bearcat M. Şándor
In reply to this post by Ralf Mardorf
On Wed, 2010-04-21 at 09:54 +0200, Ralf Mardorf wrote:

> Oops, now I see it's currently a intel hd on-board chip, so you should
> definitive use 3 Periods/Buffer instead of 2.
You know, i've tried that. If i try to start the server with 3 periods
instead of 2 i get:
10:35:01 2010: Starting jack server...

Wed Apr 21 10:35:01 2010: JACK server starting in realtime mode with
priority 10

Wed Apr 21 10:35:01 2010: Acquired audio card Audio0

Wed Apr 21 10:35:01 2010: creating alsa driver ... hw:0|hw:0|1024|3|
48000|0|0|nomon|swmeter|-|32bit

Wed Apr 21 10:35:01 2010: Using ALSA driver HDA-Intel running on card 0
- HDA Intel at 0xec100000 irq 22

Wed Apr 21 10:35:01 2010: configuring for 48000Hz, period = 1024 frames
(21.3 ms), buffer = 3 periods

Wed Apr 21 10:35:01 2010: ALSA: final selected sample format for
capture: 32bit integer little-endian

Wed Apr 21 10:35:01 2010: ALSA: use 3 periods for capture

Wed Apr 21 10:35:01 2010: ALSA: final selected sample format for
playback: 32bit integer little-endian

Wed Apr 21 10:35:01 2010: ERROR: ALSA: got smaller periods 2
than 3 for playback

Wed Apr 21 10:35:01 2010: ERROR: ALSA: cannot configure
playback channel

Wed Apr 21 10:35:01 2010: ERROR: Cannot initialize driver

Wed Apr 21 10:35:01 2010: ERROR: JackServer::Open() failed with
-1

Wed Apr 21 10:35:01 2010: ERROR: Failed to start server

Wed Apr 21 10:35:01 2010: ERROR: Failed to start server

10:35:03.545 Could not connect to JACK server as client. - Overall
operation failed. - Unable to connect to server. Please check the
messages window for more info.

Cannot connect to server socket err = No such file or directory

Cannot connect to server socket

jack server is not running or cannot be started

10:35:07.951 Could not connect to JACK server as client. - Overall
operation failed. - Unable to connect to server. Please check the
messages window for more info.

Thanks Ralf.
--
Bearcat M. Şandor
Cell: 406.210.3500
Jabber/xmpp/gtalk/email: [hidden email]
MSN: [hidden email]
Yahoo: bearcatsandor
AIM: bearcatmsandor




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Re: Will my new PC to PC setup work for Jack 2?

Bearcat M. Şándor
In reply to this post by Ed Wildgoose-2
On Wed, 2010-04-21 at 13:22 +0100, Ed W wrote:

> Funnily enough this is something that I am considering also, however,
> for different reasons. Firstly I think your best chance of success is to
> keep the quad box - my reason for looking at a dual box is that I want a
> completely silent fanless system and I have tried various designs and
> spent countless amounts of money over the years and unfortunately really
> struggled to achieve this. The problem I have always faced is that the
> machines run hot and typically they have always failed after 12-24
> months (in various ways). It's a long story, but the two box solution I
> would pick is really going to need to become a three box solution
> including some ffado firewire audio card and it's all looking fairly
> complicated right now...
A silent/fanless system is one of my reasons as well, or at least fewer fans. A 30 watt atom system is much
easier to cool than a quad system.
> Back to basics - what audio program are you using to supply audio to the
> card? Quite likely your dropouts can be fixed here?
I'm using mplayer to play video (and when i want a single track, not in
my mpd collection) and mpd, also sometmes streaming web content.
> Also you can increase your period size on the card, this usually decreases CPU load,
> plus setting appropriate realtime priorities on the correct tasks and
> generally a modern kernel can meet very low scheduling latencies (most
> of the time). I doubt your mailserver is doing more than idling and will
> almost certainly be inconsequential?
Good good. If i can off load my mail and web server to the atom i can turn of my quad at night and when i'm at work. This will save power.

> I'm guessing you probably have brutefir involved and there is a big
> tradeoff here based on fragment size vs cpu.
I will have bruitefur involved or at least ambdec or some ambisonic
 ladsp plug-in.  What is the trade off. Would you explain?
> Also upsampling to 192Khz is of dubious benefit and if this is done badly it will cost you a lot
> of audio quality, if it's done well it will absorb a HUGE amount of
> CPU... (I use libsamplerate to downsample from 48Khz to 44Khz and the
> quality is excellent, but it sucks CPU and I would dearly love to figure
> some practical way to alter the sample rate in Jack, possibly in
> conjunction with the autostart feature? Could I have two configurations
> and find some way to select the correct one to start?)
  I've been thinking about that as well. It would be awesome if Jack could just switch
sample rates depending on what the media required for no up/down sampling.
However, i'm confused a bit on how all that works. It seems like mplayer
reports sample rates depending on what i set jack to. So is Jack talking
to mplayer and mplayer is changing to match it?

> Also see my previous enlightenment - the docs on the "-t" option are
> misleading (it actually defaults to a much shorter time than stated) and
> you should probably use flag that as part of your jack commandline so
> that worst case your audio will continue in the event of some minor xrun
> condition?
I will investigate that. Thank you. Since i'm using jack 1.9.5 am i even using jackd? I seem to have a man page for it
but not an executable. (i had jack 1 installed at some point).  I'm
ahving some trouble finding good docs for jack 2.  qjackcntrl has a time
out parameter. What i don't quite get is that the timeout must be lower
than the watchdog. I have yet to find good documentaion on what the
watchdog is and how to set it

> I believe most newer "HD" audio cards actually are of pretty reasonable
> quality these days? Check the rightmark results for a basic guide. Lots
> of people will get excited about super quality DACs and I'm also guilty
> of coveting such things, but in practice I *personally* believe you will
> need a mega expensive audio setup before the DAC becomes your limiting
> factor...
What's the "rightmark" result?

> Show your config in some detail if you need more
>
> Good luck
>
> Ed W
>
> _______________________________________________
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> http://lists.jackaudio.org/listinfo.cgi/jack-devel-jackaudio.org


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Re: Will my new PC to PC setup work for Jack 2?

Bearcat M. Şándor
In reply to this post by Ralf Mardorf
On Wed, 2010-04-21 at 09:50 +0200, Ralf Mardorf wrote:

> > I'm running a full desktop on this quadcore with a mail server, web
> > server etc and i get occasional drop-outs from jack.
>
> Hi :)
>
> sounds like your sound card is an expensive, even so consumer sound
> card. Did you try to increase Periods/Buffer? What kernel do you use?
>
> Cheers!
> Ralf
I didn't see this message at first as it got filtered to the wrong mail
box.  I gave the output of increasing the buffer from 2 to 3 in another
email to you, for reference.

I'm using a custom 2.6.31-gentoo-r10 kernel.

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Re: Will my new PC to PC setup work for Jack 2?

Ralf Mardorf
Bearcat M. Şandor wrote:
> I'm using a custom 2.6.31-gentoo-r10 kernel.
>  

Hm? Kernel ok (and I guess everything is set up correctly ;), 3 periods
doesn't work (does anybody know why it might not work?), perhaps the
integrated sound chip is very bad ;). I know drop outs just when using
some virtual synths, while I did forget to change CPU frequency scaling
to "Performance" ... I assume "Performance" is default on your machine.

Ed W wrote:

> On 21/04/2010 13:37, Ralf Mardorf wrote:
>> Ed W wrote: [snip]
>>
>> Usually I do agree that 48 KHz are all that's needed, but the strange
>> thing I experienced is that for my cheap Envy24 based card, that
>> seemingly hasn't got the best converters and additional not the best
>> op-ams 96 KHz do safe sound quality, whatever the reason for this
>> might be, but this isn't why I do reply again.
>
> I believe it's safe to assume that most DAC's, especially cheaper DACs
> will work better at one freq than another. However, I would be
> surprised if this were generally audible in most reasonable quality
> designs? (eg the old AC3 codec which resampled everything to 48Khz
> internally using some really, really horrible resampler...)
>
> I should check your whole audio chain for other problems that could
> explain this, eg something resampling without you knowing it?

On my TERRATEC EWX 24/96 is an AK4524VF. Hm, for example what could
cause unwanted resampling? I need to use 512 frames to avoid issues for
the sound quality, when I used 256 frames there were issues for the
sound quality, without getting any messages. Very seldom I get some sync
warnings when using 512 frames.

The sound card was tested with several default audio distros,
self-customized distros and for test purposes on Windows too. Even when
using internal Linux audio apps 96KHz Float 32-bit the sound card
doesn't reach the quality of consumer DATs.

A friend has got another, much more expensive Envy24 based sound card,
dunno the converters and he experienced that his sound card also doesn't
reach consumer DAT quality.

I guess it's just a bad sound card.

Cheers!
Ralf
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Re: Will my new PC to PC setup work for Jack 2?

Jörn Nettingsmeier-5
In reply to this post by Bearcat M. Şándor
On 04/21/2010 06:29 PM, Bearcat M. Şandor wrote:
> On Wed, 2010-04-21 at 09:50 +0200, Jörn Nettingsmeier wrote:
>
>> not sure i understand... why don't you just put a better soundcard into
>> your quad box?
> I have experienced the difference between running an audio component off of AC power from the wall
> and battery power. I'm looking at the Atom to be able to run it off of batteries for long periods. The entire
> Atom system will use less than my cpu does in my quad box.

running a digital audio component off battery power doesn't make much sense.
you are probably searching for the "ultimate" way to reduce mains hum,
right? digital circuits don't care, and for all i know, that battery
approach is voodoo.

but *if* you still want to do it, then forget all about the atom, use
one single, decent audio pc with a good interface and a *digital*
output. then get a million-dollar oxygen-free DA converter box
hand-soldered by virgins on a dewy new moon morning somewhere in
yorkshire, and run that off of batteries. if it makes any difference at
all, it's with analog circuitry.

i'm absolutely convinced it won't help to improve your sound, but if it
makes you feel good, who am i to judge?

in any case, if you have a private hypothesis about what might improve
sound, think it through to the end. otherwise you'll be fair game to
high-end audio witch doctors of the kind that hear differences between
aes-ebu cables, and you will be relieved of huge amounts of money in
exchange for hot air.

>> but still, i don't really see the point of the whole exercise...
> To run the D/A and my amps off batteries. <an_aside>I have a Trends Audio 10.1 amplifier which is run from DC power which
> feeds a pair of Anthony Gallo Acoustics Reference 3.1s. Not the most
> efficient things at 89db or so, but not too bad considering the
> electrostatic-like tweeter. I tend to like smaller rooms so the 8-10
> watts is plenty loud. I might upgrade to a Virtue Amp (also DC) for some
> more grip on the system though,</an_aside>
>
> Thanks for helping me figure this all out folks. Glad i didn't buy this Atom system just yet.

yup. save your money, and invest in some new cds or a bottle of wine :)

best,

jörn



--
Jörn Nettingsmeier
Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487

Meister für Veranstaltungstechnik (Bühne/Studio), Elektrofachkraft
Audio and event engineer - Ambisonic surround recordings

http://stackingdwarves.net

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Re: Will my new PC to PC setup work for Jack 2?

Geoff Beasley-2
On Thursday 22 April 2010 07:00:05 Jörn Nettingsmeier wrote:
> . then get a million-dollar oxygen-free DA converter box
> hand-soldered by virgins on a dewy new moon morning somewhere in
> yorkshire, and run that off of batteries.
>
 wow!! where do i get one of those?? i'ts just gotta be good :)

(geez,ain't it the truth tho)

lol

g.
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Re: Will my new PC to PC setup work for Jack 2?

Bearcat M. Şándor
In reply to this post by Jörn Nettingsmeier-5
On Wed, 2010-04-21 at 23:00 +0200, Jörn Nettingsmeier wrote:
 

> >> not sure i understand... why don't you just put a better soundcard into
> >> your quad box?
> > I have experienced the difference between running an audio component off of AC power from the wall
> > and battery power. I'm looking at the Atom to be able to run it off of batteries for long periods. The entire
> > Atom system will use less than my cpu does in my quad box.
>
> running a digital audio component off battery power doesn't make much sense.
> you are probably searching for the "ultimate" way to reduce mains hum,
> right? digital circuits don't care, and for all i know, that battery
> approach is voodoo.
Wouldn't hooking up a battery to it make a difference to the analog portions of the card? I've heard (or think i have;
 i know how plecebo-laden hearing can be) it make a difference to an amplifier to have it hooked up to batteries vs ac mains.
Do think it might make more difference to an amp than a D/A? That would
make sense to me but i'm not sure.

I have heard the thrumming of my case fans though a driver, with my ear
against it. Not with this new amp though. So it might not matter at all.
For what it's worth these were some of the quietest fans i could find.

Thanks. You might be right about the bottle of wine and Cds at that. I
hope so. I could use some more books to read while i'm listening to Yoko
Kanno via jack.


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Re: Will my new PC to PC setup work for Jack 2?

Ralf Mardorf
Bearcat M. Şandor wrote:
> Wouldn't hooking up a battery to it make a difference to the analog portions of the card?

When I was engineer for Brauner I never heard a difference between good
filtered DC power supplies and very, very, very good filtered DC power
supplies. I never have seen very, very, very good filtered DC power
supplies anywhere else, because there's no need to do this. The only
thing that would make a difference would be discrete circuits with
selected semiconductors instead of using ICs, but even the usage of
special capacitors or special 1 cm short cable for discrete circuits is
esoteric humbug. To be honest we just did blind tests and it's said that
only double-blind tests are scientifical. The "Großtuchel" jack has
self-cleaning contacts. This is useful, but anyway nobody today is using
"große Tuchel" jacks any more. For measuring instruments the power
should be by battery. For measuring bridges you need special short
cables. But for analog audio components you never ever will be able to
hear any difference. I saw cables with overprints for the direction,
output to input, only on equipment used by audiophile people, I never
have seen such overprints on really good cables used by the best audio
studios. Some people do feel better when using hype.

OTOH what exactly should make the difference when using a battery?
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Re: Will my new PC to PC setup work for Jack 2?

Ralf Mardorf
Ralf Mardorf wrote:

> Bearcat M. Şandor wrote:
>> Wouldn't hooking up a battery to it make a difference to the analog
>> portions of the card?
>
> When I was engineer for Brauner I never heard a difference between
> good filtered DC power supplies and very, very, very good filtered DC
> power supplies. I never have seen very, very, very good filtered DC
> power supplies anywhere else, because there's no need to do this. The
> only thing that would make a difference would be discrete circuits
> with selected semiconductors instead of using ICs, but even the usage
> of special capacitors or special 1 cm short cable for discrete
> circuits is esoteric humbug. To be honest we just did blind tests and
> it's said that only double-blind tests are scientifical. The
> "Großtuchel" jack has self-cleaning contacts. This is useful, but
> anyway nobody today is using "große Tuchel" jacks any more. For
> measuring instruments the power should be by battery. For measuring
> bridges you need special short cables. But for analog audio components
> you never ever will be able to hear any difference. I saw cables with
> overprints for the direction, output to input, only on equipment used
> by audiophile people, I never have seen such overprints on really good
> cables used by the best audio studios. Some people do feel better when
> using hype.
>
> OTOH what exactly should make the difference when using a battery?

PS:

For my PCI sound card there is some "digital sounding" noise, especially
when there's no signal and all faders are torn opened. Perhaps it's
because of the used components by the card, perhaps it has to do with
shielding inside the computer case, I dunno. maybe you should take care
about this, when buying a sound card.
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Re: Will my new PC to PC setup work for Jack 2?

Ralf Mardorf
Ralf Mardorf wrote:

> Ralf Mardorf wrote:
>> Bearcat M. Şandor wrote:
>>> Wouldn't hooking up a battery to it make a difference to the analog
>>> portions of the card?
>>
>> When I was engineer for Brauner I never heard a difference between
>> good filtered DC power supplies and very, very, very good filtered DC
>> power supplies. I never have seen very, very, very good filtered DC
>> power supplies anywhere else, because there's no need to do this. The
>> only thing that would make a difference would be discrete circuits
>> with selected semiconductors instead of using ICs, but even the usage
>> of special capacitors or special 1 cm short cable for discrete
>> circuits is esoteric humbug. To be honest we just did blind tests and
>> it's said that only double-blind tests are scientifical. The
>> "Großtuchel" jack has self-cleaning contacts. This is useful, but
>> anyway nobody today is using "große Tuchel" jacks any more. For
>> measuring instruments the power should be by battery. For measuring
>> bridges you need special short cables. But for analog audio
>> components you never ever will be able to hear any difference. I saw
>> cables with overprints for the direction, output to input, only on
>> equipment used by audiophile people, I never have seen such
>> overprints on really good cables used by the best audio studios. Some
>> people do feel better when using hype.
>>
>> OTOH what exactly should make the difference when using a battery?
>
> PS:
>
> For my PCI sound card there is some "digital sounding" noise,
> especially when there's no signal and all faders are torn opened.
> Perhaps it's because of the used components by the card, perhaps it
> has to do with shielding inside the computer case, I dunno. maybe you
> should take care about this, when buying a sound card.

PPS: "digital sounding" noise stands for noise that might or might not
have digitally causes. It's a click noise.
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