Jack, I've responded in the 'Split file size and volume' thread.

Mani.

I've just tried this, and am quite surprised by the results - not what I expected at all...

Just to give some background, I can vary the base CPU rate of 133MHz by between 9x-21x using the mobo's BIOS utility. I normally have it set to 9x. But I've just tried 15x and 21x also, keeping the split file size fixed at 12MB. I used a single track for evaluation throughout; David Sylvian's 'When Poets Dream of Angels', which is beautifully recorded and starts with three acoustic guitars at left, centre and right.

9x 133MHz = 1.2GHz
The sound is as I described it before - very detailed, but edgy and fatiguing after a while.

15x 133MHz = 2.0GHz
The sound is fuller. It's almost like the split file size has been increased.

21x 133MHz = 2.8GHz
The sound is fuller still. Rich and warm. Again, it's like the split file size has been increased further.

So, increasing the clock rate has a similar effect to increasing the the split file size!!! This is not what I expected at all. Certainly, with the CPU rate set to 21x, I have no problems listening with a split file size of 12MB - it sounds so much more refined than with the CPU rate set to 9x.

The only explanation I can offer is this: With a smaller split file size, data is transferred more often (though in smaller chunks). Maybe more CPU power allows things to settle down more quickly, well before the next data chunk is sent.

Of course, God knows what happens to other things, such as RFI, with increasing CPU rates...

Peter?

Mani.

From the Schumann thread:


Interesting Jack.

My understanding is that the higher the split file size, the more 'stress' is placed on the PC. So, could it be that the changes in SQ that I'm (we're) experiencing are all due to different stresses placed on the PC with different split file sizes? Maybe.

An easy test would be for me to set the split file size and then increase the CPU clock rate and/or CPU voltage. I'll do this and report back...

EDIT But what's particularly interesting about different split file sizes is that you can hear the change in the sound immediately, within the first second or two of the music playing. I mean, you don't have to wait until the data is transferred internally in the PC, when a smaller split file size should place less stress on the system. And the sound seems to be quite consistent - it doesn't seem to change between the points where data is being transferred internally.

Does this make sense?

Mani.

Unfortunately, I don't think this is possible. You see, if I swap my RME interface with my Weiss interface, everything changes. So yes, I think I can find the best settings for my setup, but I really doubt they'll be the best for anyone else. Hey, but who knows? I'll certainly do this and let you know what I come up with...

But for now, I'm finding that if I play 16/44.1 with a split file size of 65 (my favourite 'fixed' setting), then I need to play QAP with 70 or so to take a slight edge off and bring the bottom end back. Not a big difference in split file size at all - certainly no where near the increase that native 24/176.4 seems to require to sound right.

I think it depends what you mean by 'sounds better'. The bass seems to tighten up with lower split file sizes., but can lose some of its weight and fullness. For example, a grand piano can start sounding like a smaller stand up. Generally, the sound can get too thinned out.

But I haven't really listened out for differences between various volumes - if the volume becomes yet another variable, I really will lose the plot and might just descend to using WMP.

Mani.

Ah, and there's the rub, as a certain gentleman, who was born 10 Km down the road from me in 1564, would say.

But as Peter has said, he won't be able to determine this on his own. (I'm not sure if I trust his ears at his age anyway - he's started hearing 'rain'!)

Mani.

Without meaning to stir the pot, I hope people realise how important this topic is. It's started to make me think that any comparisons that I've made in the past between, say, 16/44.1 and 24/176.4 files are invalid because I've not optimised the split file size for the two resolutions. For example, at 100MB, most 16/44.1 tracks sound OK. But 24/176.4 tracks sound too bright and forward. At 400MB, this brightness goes... but 16/44.1 tracks now sound too dark.

We've GOT to get to the bottom of what's going on here...

EDIT

Oh, and some people who use a large split file size may not agree that it sounds 'dark'. But I bet these people are of the 'ultra-low latency' brigade, which tends to sound brighter and more forward.

EDIT EDIT

Actually, this wasn't what I meant to say AT ALL.

It seems to me that the split file size has a simlar affect to the sound as the device buffer size - the larger the darker, the smaller the brighter. Now, for ultra-low latency you'll obviously have a low device buffer size, BUT... you're probably going to have to set the split file size quite low also to get glitch-free palyback. So, can you now be sure that it's the low latency that's causing the change in sound, and not the low split file size?

I think that's what I meant to say!

Mani.

I'm not sure I've got much to say really. But I agree that the Schumann device seems to have more affect on the listener than the equipment
necessarily.

But hearing rain drops? Oh, I've been hearing the rain drops alright - to such an extent that my basement is now flooded! But I'm pretty certain that I've been less stressed than I might otherwise have been. For example, many of my CDs, including many very expensive MFSL releases etc, have been ruined (not the discs themselves, but the booklets), and I'm just going around thinking, oh well it could have been worse - at least it was clean rain water and not sewage water...

But one thing the Schumann device isn't helping with is the now so obvious affect that the split file size has on the sound. It's really bugging me for some reason. I think it's because unlike the Q knobs, which once set you can leave alone, the split file size seems to need adjustment on a track-by-track basis, which is starting to infringe on my relaxation/presence and ultimately my listening pleasure.

Mani.

Marcin, I think this is related to Peter's 'warning' above. QAP will be introducing additional processing that will need to be factored in.

In any event, try what you did with a native 24/176.4 file and see what happens.

Mani.

Of course, it could just be that the 'sweet spot' for 16/44.1 material is always around 60MB irrespective of file size (with DAC set to 16 bits and assuming no extra processing in XX). In which case, one would expect the 'sweet spot' for native 24/176.4 files to be around 480MB (with DAC set to 32 bits and assuming no extra processing in XX).

But I kind of hope that the optimum split file size is actually related to the track size, and that this can in some way be automated.

Mani.

Hey Peter, forget these pleas for help... just threated to introduce yet another Q knob instead.

Mani.

OK, there's not a lot in it between a split file size of 330MB and 495MB for this 330MB 24/176.4 file. But I prefer the 495MB - it really does seem to hit the 'sweet spot'. Pure coincidence? Maybe...

Marcin, my signature is wrong actually. I used to use 'no scheme' up until a few months ago when I switched from 4 to 2 cores in my BIOS. With 2 cores, I use 'scheme 3'. But I have to admit that I've always found it difficult to hear differences in SQ between the various schemes. If you're still using a single core, then I suspect 'no scheme' will be best for you, no?

I've updated my signature...

Mani.

Peter, you're right of course. My DAC is set to 32 bits.

I started at 1000MB and then jumped to 12MB to hear the difference, which was as I described. I then continued to increase the split file size until the sound between the recording and vinyl 'equalized'. 330MB seemed to do the trick, but I'll try 495MB... I'll also try this with my Weiss interface, which does work at 24 bits.

Mani.

This post has nothing to do with volume, only split file size.

Firstly, Peter please NOT another Q knob for this - I'll go insane...

But the split file size clearly DOES change the sound. Lower values sound 'clearer', but perhaps too 'edgy'. Higher values sound 'fuller' but perhaps too 'woolly'. It therefore seems logical that there should be a good middle ground and that's what I've been trying to establish.

Again, I used my 24/176.4 recording from vinyl and compared the sound directly to the vinyl.

But everything is inextricably linked - all the other parameters in XX have an affect, so finding an absolute value for the split file size was going to be difficult. Without going into details, I found that my ADC/PC/DAC chain is most transparent when I use a device buffer size of 1024. (This has nothing to do with XX though.) With this set, I played around with the split file size.

And you know what, I got the best sound when the split file size was... THE SAME SIZE AS THE FILE BEING PLAYED!!! (For my 24/176.4 file, it was 330MB.)

Now, how this translates to multiple files and playlists with different formats, I'm not sure. But assuming there is something in my findings, wouldn't it be great if XX could set the split file size automatically, track by track, based on the size of each file being played.

This way we'd get the best sound... and remain relatively sane too... although it has to be said that all long-time users of XX are waaaay beyond this point already.

Mani.

As an interesting aside (and a welcome 'Time Out' from 'Take Five'... ), Blue Coast Records are offering some free downloads here: http://www.bluecoastrecords.com/cas-2010-downloads.

My understanding is that these were originally recorded in DSD on a Korg. They have been converted to PCM in two resolutions: 16/44.1 and a 24/96. It's quite interesting to compare these two versions.

(But I have to say that I really don't like DSD. I wish they'd just have recorded in hires PCM in the first place.)

Mani.