RAMDisk

[manisandher]

Without meaning to steal anyone's thunder (I hope you don't mind Marcin), I thought this topic was worthy of its own thread.

So, how exactly can running XX from a RAM partition improve its sound? I have a hypothesis which is related to this thread over at CA: http://www.computeraudiophile.com/content/Monster-raises-its-headagain.

Could it be that its all down to the SATA cable? Presumably, running XX from RAM would eliminate any ill effects that the SATA cable and HDD/SDD might be introducing.

It's a hypothesis (a far-fetched one, I know), that's all.

Mani.

[Raj.V]

Mani,

regarding your point on the SFS & Ramdisk, here is my system observation. (Note: my system may not be the most revealing.)

Yes, it still does make a difference with the SFS settings even with my Vista OS. For optimal SQ, I have to keep mine at 120-150 (I have always upsampled 4x).

But, interestingly I hear no difference in core-appointment settings, which I used to hear when playing with XXHE on harddisk.

Raj

[boleary]

So, in the Ramdisk Configuratio utility, what disk size should be selected; I have 4 gigs of ram on the computer? Also, should one select Fat 16 or 32? n the "Load and Save" tab, which checkboxes should be checked, I presume one would want disc image saved but.....Lastly, do I reinstall xx directly on the Ramdisc drive? Thanks in advance for your help!

[Raj.V]

I just used FAT16 and used the size which was already displayed (you should increase it) if you want to play flac or "copy to XXHE HD".
Click run. That's it.

Unzip XXHE in the newly created ramdisk. Create XXData folder. Basically the usual steps...

Run XXHE from the new Ramdisk and start also the original one from your HD - then you can A-B the XXHE/HD and XXHE/Ramdisk.

Raj

[PeterSt]

Select FAT32

I used 1GB for it, and can normally play an album.

Copy your current XX folder onto it, but use the complete structure. Thus, supposed you now have XX in

c:\Player\XX-0.9z-2\

make that folder on the RAMDisk and copy the complete contents, including the subfolders. Better leave out the TemporaryData (log data) to save some space.

Sadly you will have to set all your settings again.

When after a reboot the driver letter is the same for the RAMDisk, you can again copy the XX files, but now the settings will have been preserved.

About saving the "image", so all goes automatically after a reboot ... I must test this, and therefore now reboot this PC.

Peter


PS: Raj was ahead of me. FAT16 should work too -> it only allows less files (but think in millions).

[PeterSt]

The Save Image thing works by itself, but it seems that as soon as you use this (see 2nd tab), the RAMDrive isn't created automatically after a reboot. However, starting it up again, will now recreate the contents automatically. So, very much workable.

[Gerard]

The Save Image thing works by itself, but it seems that as soon as you use this (see 2nd tab), the RAMDrive isn't created automatically after a reboot. However, starting it up again, will now recreate the contents automatically. So, very much workable.

Peter,

Can you make this in XX? Use a button to do this automatically??

 

[manisandher]

No, once you select 'load disk image at startup' and also 'save disk image on shutdown' then everything becomes automatic. You will notice that your PC takes longer to shutdown, as RAMDisk saves the RAM disk image. On startup, the RAM disk is created automatically with XX and all the previous settings totally intact.

That's how it works on the 3 machines I've tried it on here.

Mani.

EDIT

I forgot to mention, once you've pressed 'start RAMDisk' and everything looks OK, then just close the window - DO NOT press 'stop RAMDisk', unless you actually want to delete the RAM disk and XX (if you've installed it there).

[boleary]

Thanks to all. 

[Nick]

My thoughts on why RAM disk work for music go back to the basic architecture of a PC. Music is generally improved by PC responsiveness (speed) in the right parts of the hardware, OS and HighEnd processes. Micro or even pico seconds must surely count in some areas. The responsiveness of the PC to the few software processes actually involved in playing music is what all our OS tweaks are about in the end.

This is NOT all fully worked through as a theory but...

For XXHighend to read from a Sata HDD, the CPU’s read request has to be transmitted from OS > SATA drivers > North Bridge > South Bridge > SATA implentation of the south bridge > the HDD itself. The HDD heads then find and read the data and load into the HDD cache if it’s not already there. To return the data from the HDD to XXHighEnd the data follows the reverse route; HDD Drive > Cache > SATA > southbridge > northbridge > CPU.

Disk sub subsystems are very well optimised for speed but not to the same level as CPU to RAM by DDR data transfer. If you assume that a the SATA HDD and RAMDisk software drivers are equally efficient in terms of  code and use of interrupts (big assumtion), you can seen from the diagram in this link http://www.tomshardware.com/reviews/intel-p45-chipset,1961-3.html that the access of the CPU to RAM is both shorter and conducted over the higher bandwidth parallel channels of  DDR.  Much faster than CPU to a HDD access.

My guess is that the extra speed of access and data transfer, translates to MUCH more timely delivery of the data to XXHighEnd processes. RF and cables may also play a part but I’m guessing timing is the main influence.
Just a theory    any thoughts ?
Nick.

[Marcin_gps]

Nick, I'm sure you're right about it. I'll just add that from my experience lowest latency works/sounds best.

[Raj.V]

Nick,
your theory definitely holds water.

If the idea is to keep the transfer rates high and the paths short... perhaps it will help to have XXHE on Ramdisk and the music on a SSD connected through PCI slot. Then South bridge is out of the picture.

Is that possible???

Raj

[Nick]

Raj,

When I chose my mobo I didn't know what chipset to go for and what would work best for PCI based interfaces so I did a bit of reading on chipsets. Nothing too technical but I recon RAMDISK takes the southbridge out of the equation (and a lot else as well).

Nick.

[Josef]

I'm not sure I buy Nick's theory when it comes to XX:
For simplicity, let's say there is only 1 track in playlist - As I understand, before playing XX will first perform conversion to WAV (if needed) and then load resulting file into a pre-locked RAM - Only then, it starts playing i.e. reading music bits from there.
So the path bits have to travel to get to XX engine is identical to one used with RAM disk: no SATA cables magic etc...bits come directly from RAM in both cases.

If, however, RAM is not locked but merely 'allocated' and memory-mapped files API is used instead then it's a different story.... 

Peter, can you comment if this is not too much proprietary info you'd rather not disclose?

[Nick]

Josef,

Now I think about it, I think you are right. Both HDD play and RAMDisk play are playing from RAM already !!

I think I remember reading that preconverted files are loaded to memory before play (except WAVs that are not processed which need Copy to OS setting). This means as you say both HDD and RAMDISK are playing from RAM.

What is making the difference ??

Nick.