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In Reply to: RE: Vista 32-bit max = 4 Gig posted by Scrith on January 22, 2009 at 19:15:45
Windows is happily reporting that you have 4GB installed, but that doesn't mean it can actually use all of that!Yeah I guess its really a mute subject seeing that my memory usage never goes further than 20% anyways, so even IF Vista were only using 3G of RAM I never use more than .6G of RAM anyways....:-)
During normal listening the machine is hovering around 14% memory usage...keep in my this is 'after' it loads the entire CD to RAM.
I guess that would explain why there is no difference between the 4G machine and the 2G machine running Vista.
So what do you do, that requires 8G of RAM???? Do you use your machine for gaming???
Karma Means Never Having To Say You're Sorry
Edits: 01/23/09Follow Ups:
Yes, I play and create 3D games, do software development in Visual Studio, use spreadsheets, surf the web, and play audio in Foobar2000. All at the same time! With no difference in audio quality between running all that and running just Foobar2000. I continue to be mystified by all the attempts to minimize system usage and resources in order to get "high quality" audio around here...audio playback (assuming no resampling or other DSP-like manipulation of the data by the audio player) is a trivial task for any modern computer (much easier than, say, surfing web pages with pictures on them). My Foobar2000 CPU-usage is usually 0-1% of CPU resources (according to the Task Manager).
Of course, a quad-core extreme edition Intel processor w/ 8GB of fast RAM, fast hard drives, a nice motherboard, 1GB video card, etc. doesn't hurt. :-)
Scrith wrote:
> > "I continue to be mystified by all the attempts to minimize system usage and resources in order to get "high quality" audio around here - audio playback . . . is a trivial task for any modern computer."
Audio playback is indeed a trivial task for a modern computer but that is far from the whole story. The optimal presentation of the processed data to the outside world is much less trivial.
As we all know, hearing is sensitive to remarkably small timing errors in the digital reproduction of music or, in the jargon, to “jitter”. (That the term is as much abused as used in audiophile circles is unfortunate but it is nevertheless clearly defined and well understood by audio engineers.)
Judging by posts on this list, it seems that many do not understand that the final stage of PC audio reproduction is a 'real-time' process which, absent design measures to tackle it, is especially prone to “jitter”.
The process cannot be optimised by throwing computer power at it. On the contrary, theory and experience suggest that minimising, not maximising, data processing power is a more fruitful route.
The designer (amateur or professional) is attempting to handle signals that require the rigour of instrumentation electronics in the worst possible environment - inside a desktop computer.
A major cause of the degradation of the audio signal is the electrical noise in the computer. One obvious way to address this is to select quality components and to configure or modify them to minimise the noise they generate.
A related approach, a feature of the cMP2 project, is to dedicate a small and relatively low-cost computer exclusively to playing music and to ‘underclock’ it to the slowest speed at which it can perform satisfactorily. This reduces power draw and thus noise pollution.
It is difficult for amateurs to quantify results but there are enough subjective reports to give both approaches credibility.
Another major source of timing errors is (for lack of a better term though one is certainly needed) “operating system jitter”. This reflects the fact that, while audtion is a real-time process, computer operating systems are not.
This is obvious at the macro level: at the drop of a hat, Windows does things when you least want it to: e.g., when an AV update slows everything down.
In extreme cases, the listener experiences “drop outs” - detectable breaks in the audio stream. No one would dispute the need either to have enough computing power to avoid the problem (as Scrith recommends) or to reallocate resources to tackle it.
Optimisation procedures similar to those recommended for cMP2 (though less thorough) are described on the pro-audio web sites and are commonplace when running any processor-intensive software.
Increasing computing power may avoid breaks in the data stream but it is inevitably accompanied by increased noise pollution and thus tends to be self-defeating: it improves the availability of music data but not necessarily its integrity.
For “high-end” reproduction, a more fruitful approach is to tackle OS “jitter” where it is less obvious but probably more critical - at the micro level.
The problem is well expressed in the documentation for the useful Windows utility DPC Latency Checker:
“Processing of streaming data in real-time is a very challenging task for Windows-based applications and device drivers. This is because by design Windows is not a real-time operating system. There is no guarantee that certain (periodic) actions can be executed in a timely manner.”
(See: http://www.thesycon.de/dpclat for the full text.)
We can squabble at leisure over the relative merits of the cMP2 project and of various Linux setups but both adopt this approach and report good results.
It can be demonstrated (and, to a limited degree, quantified) using DPC Latency Checker whilst successively performing cMP2’s optimisation steps.
The documentation for cMP2 reports jitter levels measurements which, while incomplete and thus inconclusive, nevertheless offer strong support for the approach.
In summary, the argument is that suppressing electronic noise and reducing the response time of an operating system to its core task both significantly improve the quality of computer-based music reproduction but that throwing computing power at it is less fruitful.
If the user's aim is simply to keep Foobar busy while doing other things, then fair enough.
But if the aim is to achieve the best possible reproduction of music from a computer, it is possible to do a great deal better with a slightly unorthodox approach.
Critics are free to deny the extent of the claims made by proponents of the techniques described here or to question the merit of some of the measures they propose.
However, there is nothing especially esoteric and even less that is mystifying about what they are doing. True, it needs good software and some innovative thinking (who'd think of using a Fit-PC to play music?) but the rest is basic electronics. No more.
Best
Dave
Of course, a quad-core extreme edition Intel processor w/ 8GB of fast RAM, fast hard drives, a nice motherboard, 1GB video card, etc. doesn't hurt. :-)
Wow!!!
You got that right!!!!!
Karma Means Never Having To Say You're Sorry
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