Topic: Better sound quality and depth

I have only just discovered that it is possible to have excellent sound quality in pianoteq without using much CPU. You guys probably already know this so I may be a bit slow but I'll post it anyway just for those who, like me, didn't know this neat little trick!

In options under devices select a sample rate of 48000Hz
In options under performance select an internal sample rate of 12000Hz
(your host sample rate of 48000Hz which you have just selected under devices will show below the 12000HZ internal sample rate).

Now you have excellent sound at minimal cost to your CPU!

Sorry if I'm teaching my Grandmother to suck eggs!

Last edited by sigasa (30-07-2009 00:43)

Re: Better sound quality and depth

When the Pianoteq sample rate differs to the device sample rate, what does the sample rate conversion?  I haven't tried it yet, but if the quality is still excellent with the differing sample rates, that's great.

Greg.

Re: Better sound quality and depth

Gave it a quick try with the CP80 - it lost a fair bit of it's metallic edge. I'm sure it'd be pretty good with the acoustics though. (haven't bothered testing these)

Greg.

Re: Better sound quality and depth

Nice. I'm hearing noticeably less bite and dynamics (and volume?) in the acoustics, too, but these steps do create a very playable instrument that only takes up around 10-15% of the cpu.

I'm not sure I understand what happens. The first step raises the sound card\chip sample rate and the second lowers the program's sample rate, so the effect is to decrease the quality of the source material (with the 2nd step, on the Performance tab) and resample it, in a sense, at a higher rate than by default (with the 1st step, on the Devices tab)?

Somehow, I would expect the sound to degrade much more, given the deep cut in the Performance sampling rate.

Last edited by Jake Johnson (30-07-2009 18:09)

Re: Better sound quality and depth

IMHO the reason it works pretty well is that pianos simply aren't *that* bright.  (i.e harmonically rich) Very bright instruments like cymbals would suffer more.

I suspect the reason for raising the device sample rate to 48000 is just to allow Pianoteq to have it's internal rate "a little bit higher" than it would be otherwise. If the device rate was 44100,  Pianoteq's rate would be 11025, because Pianoteq appears to restrict it's internal rate to "integral submultiples" of the device rate.  At such a low internal sample rate, every little bit counts. At a device rate of 48000, we can also set Pianoteq to 16000 - that might be a more reasonable compromise for some instruments.

Greg.

Last edited by skip (30-07-2009 20:45)

Re: Better sound quality and depth

"If the device rate was 44100,  Pianoteq's rate would be 11025, because Pianoteq appears to restrict it's internal rate to "integral submultiples" of the device rate."


Skip,

I'm getting confused--I've always just kept both sample rates at 44100. I thought this was the default, but I may have changed the settings at some point and forgotten...

Re: Better sound quality and depth

You're right Skip, 16000Hz would be a better compromise. Having said that though, 24000Hz sounds wonderful and is still easy on the CPU! Actually, 48000 / 24000 is still easier on the CPU than 44100 / 44100! Also all the harmonics are audible at this setting (48000 / 24000). Personally I like the sound with the 48kHz / 24KHz and think it superior than that obtained when using 44.1KHz / 44.1KHz. Added to that the obvious drop in CPU usage and I think we're on to a winner!
http://www.forum-pianoteq.com/uploads.p...5650fc1742
The link is to a demo using 48KHz / 24KHz. Bare in mind that the quality of .mp3s' are not as good as .wav files!

Last edited by sigasa (30-07-2009 23:31)

Re: Better sound quality and depth

Jake Johnson wrote:

I'm getting confused--I've always just kept both sample rates at 44100. I thought this was the default, but I may have changed the settings at some point and forgotten...

It is the default, and that's how I run mine too.

What I meant was:
Given that the idea posed in this thead is to try to save a *lot* of CPU cycles by reducing Pianoteq's sample rate a lot,  rather than dropping it to 11025Hz, we can get back a *bit* more fidelity, consuming only slightly more CPU cycles,  by increasing it to 12000Hz. But to do that, we have to *also* change the device rate to 48000Hz - 12000Hz simply isn't listed as an option if the device rate is 44100Hz.  If we restricted the device rate to 44100Hz, that limits us to 11025Hz and 22050Hz, with no intermediate settings - it's a big jump.

Greg.

Last edited by skip (31-07-2009 00:12)

Re: Better sound quality and depth

I see. Sorry not to read it correctly.

Re: Better sound quality and depth

That's ok pom-pom man. 

Greg.

Re: Better sound quality and depth

Guys, are you nuts? lol  (meant kindly) -
seriously though, go read about the Nyquist Theorem...

The highest frequency pianoteq can produce is HALF the sampling rate it uses. Using 12kHz would mean no notes or harmonics above 6kHz!! That's not much better fidelity than your average telephone...

Re: Better sound quality and depth

But it sounds better than that.

Re: Better sound quality and depth

feline1 wrote:

Guys, are you nuts?

no but squirrels still like me!

Re: Better sound quality and depth

sigasa wrote:

http://www.forum-pianoteq.com/uploads.p...5650fc1742
The link is to a demo using 48KHz / 24KHz. Bare in mind that the quality of .mp3s' are not as good as .wav files!

The mp3 is 44.1 kHz, so here's also some resampling done to further change the sound. You should have made a 48 kHz mp3 as well.

Also, you could have explored more dynamic levels in that improvisation, so that we can hear what is exactly lost.

I'm still using my PTQ3 on 48k/48k.

Hard work and guts!

Re: Better sound quality and depth

Jake Johnson wrote:

But it sounds better than that.


well it shouldn't
lol

Re: Better sound quality and depth

feline1 wrote:
Jake Johnson wrote:

But it sounds better than that.


well it shouldn't
lol

Actually, the highest note on the piano is around 4300 Hz and low notes don't produce harmonics much higher than 7000 Hz, so it makes sense, though I haven't tried it myself.

Re: Better sound quality and depth

Gilles wrote:
feline1 wrote:
Jake Johnson wrote:

But it sounds better than that.


well it shouldn't
lol

Actually, the highest note on the piano is around 4300 Hz and low notes don't produce harmonics much higher than 7000 Hz, so it makes sense, though I haven't tried it myself.

I worry that the strike transients would have higher freqs, though, which would explain the loss of apparent brightness and amplitude when playing harder.

Last edited by Jake Johnson (01-08-2009 16:40)

Re: Better sound quality and depth

Yep, 48000Hz / 48000Hz is best! I've just been comparing and comparing and yes, the only way you're actually gonna get the best out of pianoteq is to use at least 48000Hz / 48000Hz. But for those who don't mind loosing a little presence and brilliance - especially noticed in the way some notes at certain velocities at 48000Hz / 48000Hz sound like kissess which is lost at any lower sample rate - go ahead and save on CPU!!!

Last edited by sigasa (01-08-2009 22:00)

Re: Better sound quality and depth

Gilles wrote:

Actually, the highest note on the piano is around 4300 Hz and low notes don't produce harmonics much higher than 7000 Hz, so it makes sense, though I haven't tried it myself.

RE: the 7kHz, I said words to this effect recently, however I can't find anything to substantiate this - do you happen to have a reference?

Greg.

Re: Better sound quality and depth

skip wrote:
Gilles wrote:

Actually, the highest note on the piano is around 4300 Hz and low notes don't produce harmonics much higher than 7000 Hz, so it makes sense, though I haven't tried it myself.

RE: the 7kHz, I said words to this effect recently, however I can't find anything to substantiate this - do you happen to have a reference?

Greg.

Actually, this is a bit empirical for me. I just looked at some of my spectrum analysis graphs and never got any significant values above 7 or 8 KHz. (See my post in the "Two more pop-rock Yamaha videos" thread.)

8KHz is sometimes given when searching the web for this information but with no justification.

Still I managed to find the following reference under Google books which seems trustworthy and seems to agree.

http://books.google.ca/books?id=RUDTFBb...mp;f=false


By the way, my value for the highest note is off and closer to C#8 probably due to octave stretching.

Re: Better sound quality and depth

Thanks Gilles - much appreciated. (I was beginning to think that I had dreamt it!)

Greg.