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[soundcheck]

Hi folks.

Just loaded MC12.

I am running MC as pure audio playback engine.

Since RAM buffered playback offers better sound quality, I would like to push one issue again:

The function is more or less already existent.

The buffering during playback is still only configurable by registry changes.

Would be nice to have that in a config menu.

As a maximum setting I'd like to see a full file buffering option as it is available in other audio-applications such as foobar.

Should be really not too difficult to implement.

Until than I am running my RAMdisc.

Cheers
Klaus

[Matt]

Since RAM buffered playback offers better sound quality, I would like to push one issue again:

Could you explain why you think this one more time?

Media Center is bit-perfect whether the file comes from file I/O, TCP/IP, a ramdisk, etc.  The digital bitstream delivered to the soundcard is IDENTICAL.

The only argument I can think is the hard drive head movement makes a little noise (and an electromagnetic field).  However, a good drive in a good case (P180, etc.) is next to impossible to hear.

[hit_ny]

Still interested to understand the reply

I am not saying latency is causing distortion. Latency is just another word for delay and that's what's all about it. For playback it is not a real issue as long as the latency is kind of linear.
What I am saying is that non-linear latency-jitter or jitter is causing distortion, if it is induced to the data-stream which goes (realtime) right into the DAC-chip.
The RME side explains very well the differences.
If your soundcard and its drivers are able to cope with this non-linear-latency-jitter-in-the-datastream fact, you shouldn't have a big problem, as long as your soundcard does a real great job.
I know that some high-end soundcards/DACs do some buffering and reclocking before the stream leaves towards the DAC-chip to avoid these kind of Latency-Jitter or Jitter problems.

The major source for latency jitter is the interrupt handling. And you can't get around it.
This is by the way the reason why UNIX systems are the prefered systems when talking about real-time applications.

Example: Let say you got an USB soundcard. Playback and  datastream is running towards your soundcard. Suddenly "Interrupt" pops-up  saying - "Hold on - I have to read the data from HD first" to fill the 6000ms buffer. This one has higher priortity than USB. Next One. Graphic Card is saying: Stop if have to refresh the GUI.
And there are at least 40 other processes running from which a lot of processes have higher prority than the USB-bus in charge for your Latency-free realtime datastream.

My theory:  If the buffer is 6000 or 12000 that's  not the key issue. The key issue is to avoid long interrupts from e.g. your Harddisk during playback, which potentially influence negatively the USB realtime stream at a point in time where there is no chance to get the Latency-Jitter effects cleaned up anymore.
 
Anyhow. I think this is well known fact - at least to MS. I hope that the "exclusicve mode" in Vista will limit these kind of impacts.

[soundcheck]

Hi there.

In the meanwhile I think it is really the extra noise the harddisc produces, which has a kind of impact on the system and indirectly on the stream.

Anyhow I don't actually care where the sound degradation is orignated. There are others out there who might find that out. 

Perhaps we'd check with hit_ny! 

I am running also Samplitude, a professional mastering software. These kind of features are basic for such applications and even foobar is delivering it.

Would be a nice to have!

Cheers

[Matt]

In the meanwhile I think it is really the extra noise the harddisc produces, which has a kind of impact on the system and indirectly on the stream.

I still haven't heard a reasonable argument about how a hard disc hurts sound quality. (any more than a northbridge chip, PCI card, etc.)  It sounds like snake oil.

However, if you're really worried, my advice would be to invest in an outboard DAC or outboard soundcard.  Then only a digital bitstream leaves the computer.  You could also use NAS harddrives so no hard drives are in your computer.  This is better than prebuffering because prebuffering still would spin a drive up and down and read from it for a while.

I am running also Samplitude, a professional mastering software. These kind of features are basic for such applications and even foobar is delivering it.

Mastering software often needs tricks to reduce latency.  (think MIDI simulation from a hardware keyboard, or instant application of mixing effects)  This doesn't really apply to playback programs like Media Center where a 100ms delay in the DSP chain for a change to take effect is not such a problem.

[soundcheck]

I still haven't heard a reasonable argument about how a hard disc hurts sound quality. (any more than a northbridge chip, PCI card, etc.)  It sounds like snake oil.

However, if you're really worried, my advice would be to invest in an outboard DAC or outboard soundcard.  Then only a digital bitstream leaves the computer.  You could also use NAS harddrives so no hard drives are in your computer.  This is better than prebuffering because prebuffering still would spin a drive up and down and read from it for a while.

Mastering software often needs tricks to reduce latency.  (think MIDI simulation from a hardware keyboard, or instant application of mixing effects)  This doesn't really apply to playback programs like Media Center where a 100ms delay in the DSP chain for a change to take effect is not such a problem.

Hi Matt.

I am not worried all.  The way I am running my setup right now is great working and shows more than obvious sound improvements. I am really happy with the outcome.
And I do not intend to discuss this fact.
From convenience point of view it would be a nice-to-have feature if it was integrated into MC. Programming effort should be very low here.

Anyhow - If you folks don't care. I don't care.   

As far as you know MC is doing 6s pre-buffering. And this is the reason why I ask for full file buffering, as you said this 6s prebuffering is useless since the drive would always be spinning.
Spinning up the HD at the end of the track doesn't harm the sound at all. If it is done smart, the loading won't be even recognized. To load a 30 MB average wav-track into RAM won't take
more than 2s. To load a complete CD into RAM takes less than 20s.

I am running an external DAC. Playing with the buffer sizes and latencies, which is possible with Samplitude and the used ASIO driver will have a great impact on sound quality! If done wrong
it can really mess up your sound. It is not a PRO or midi issue only!

BTW I am running a different HW-profile for audio. You can switch off  - wlan, network, internal sound, bluetooth asf. This also makes a difference!

Before I start using NAS drives, I try to get my PC, with its given configuration, best configured as possible.

Cheers
 

 

[chrisr]

This topic of loading full music files into memory seems to be getting some attention.  Apparently Soundcheck is not the only one hearing a benefit from playing a full music file from a memory compared to buffering from a hard disk:

http://www.novaphysicsgroup.com/MemoryPlayback.html
http://www.lessloss.com/computer_audio_usb.html
http://www.audiocircle.com/circles/index.php?topic=37387.msg334742#msg334742
http://www.digido.com/bob-katz/jitter.html

I don't know if it makes a difference.  It might be snakeoil or placebo.  But if it does help, it would be great to be able to do this.  Or at least be able to try it...

I have no hidden agenda here, just a quest for best possible sound and I love MC12.  I suppose one could use a ramdisk, but they only hold a few songs--there is no functionality to automatically move new files into the ramdisk from a playlist.  Buffering a full song would overcome this problem.

[Listener]

MC 12 is a well-engineered product that provides a lot of function and does it reliably.  That took real knowledge of computer and software architecture and lots of work.  Thanks, JRiver.

I would hate to see JRiver people diverting their resources to implement RAM based playback or any other cure to hypothetical problems that a few people are completely certain they can hear. 

The audio world is awash with people proclaiming that they can hear differences where there is no reason to believe that there should be differences.  There isn't much effort going into careful investigation to verifying such claims and even less to understanding how such differences might occur.  Just claiming to hear a difference is enough to starting proclaiming that the problem should be fixed.

One thing is seems likely: there will always be more people claiming that they hear a new difference.  Placating them is a never ending task that will only make MC 12 worse.

The Novaphysics and lessloss material is full of incorrect incorrect statements and wild claims.  The material on "purifying" audio by compacting memory is completely irrelevant to the real process of playing audio.  Buffering audio data is necessary for computer based playback to work at all.  Once you tune the playback process so that the buffers never run dry, it is not necessary to have audio data stored contiguously in RAM.

The lessloss link lists a number of hypothetical effects that are claimed to produce audible differences in sound quality and suggests remedies.  For example, turning off the monitor is claimed to produce an audible difference.  Why not just turn off the entire computer and go back to using a CD player?   What's missing here is any verification of the claims of differences.

Look for threads about the MemoryPlayer and lessloss and you'll find that their claims have been criticized strongly.

The existence of companies like Novaphysics and lessloss.com is a perfect solution to the "problem".  Let's let JRiver stick to sound engineering and the Novaphysics and lessloss people can design fantasy based products for their audience.

Bill

[JimH]

This topic of loading full music files into memory seems to be getting some attention.  Apparently Soundcheck is not the only one hearing a benefit from playing a full music file from a memory compared to buffering from a hard disk:

Horse feathers.  Bogus.

There are many reasons for playback problems (drivers, virus checkers, etc) but the fact that the bits comes from a hard disk instead of from memory is not one of them.  This is like debating creationism.