Samplerate at 96k

[SVSX]

Hi folks, i allways was recording my stuff at 44.1k. After watching some videos about audio aliasing and folding back of overtones into the audible range, i've tried to set my samplerate to 96k. Now when i compare Kontakt 6 Hybrid Keys sound quality i can hear a big difference.

Problem is that it shouldn't be that much of a difference, or am i wrong? Its extreme, so that you can see it on your spectrum analyzer. The bass sounds much louder and the frequency curves are much thicker, than on 44.1! Something seems to be wrong here. Whats the cause for this? Did someone have similar results? 

I'm working on a ESI Juli@ PCI interface btw. Maybe its converters cannot reproduce  higher samplerates right?

[SVSX]

This is a Vital sound i've recorded as an example. 

96k SampleRate.mp3

44.1k SampleRate.mp3

Edited December 5, 2021 by SVSX

[azslow3]

That is well known effect. It comes from bad math inside plug-ins, but used as an argument 96kHz sounds "better".

In Cakewalk you don't have to do everything in 96kHz (that is one time decision since you can't change sample rate in existing projects),  you can use "local up-sampling" when make sense http://www.noelborthwick.com/cakewalk/2015/10/24/improving-your-synth-sounds-with-real-time-upsampling/

Some people just use 96kHz for everything, to not think about possible troubles with plug-ins. If you do that,  check what you send to your monitors doesn't have high frequency (apply LPF to the limit of your hardware).

[SVSX]

Thats interesting ?

Do you know which one of these is the right sounding one? The 96k file or 44.1?

[azslow3]

What you mean by "right"? May be the person who has created the settings was using 44.1kHz, and so that sound is intended. May be he/she was using 96k. And it can happened it was 192...

There are way more frequencies in 44.1 version. I am not an expert, but that can be aliasing results from math. I mean everything over 22kHz calculated in 44kHz rate produce something inside 22kHz. Your "96kHz" mp3 is 48kHz, only you can see (on original 96kHz track) what is inside ultra high range.

Plug-ins/preset developers who care check that generated (also intermediate) frequencies are always in reproducible (by sample rate) range, and oversample + LPF when not. Other don't care. Fortunately Cakewalk can do that too.

[SVSX]

If you are interested i have some pics taken from Span:

 

[azslow3]

I guess everything over ~20k (as you can see quite a lot...) lands somewhere under 20k (with full "weight"). The synth can also try to use resulting frequencies later in the own chain. Just imaging a band 30-40kHz is used to modulate sub 100Hz band. What I mean, end result is not limited to just digitally aliased frequencies, any kind of distortions can be triggered.

BTW such spectrum is a definitive confirmation the plug-in/preset creator has done something wrong. Audio plug-ins should not produce ultra-sonic components. That is no longer "audio" since there is no equipment which can reproduce it (and even in case such equipment is created, no one is able perceive it, except resulting analog world distortions and aliasing).

[SVSX]

Thanks azslow for your knowledge.  Crazy! I tried different VSTi's and some sounded similar, some had a huge a difference, like my example here from Vital synth. The other bad example i found was Kontakt 6 "Hybrid Keys 2" Library from Native Instruments.

So i keep staying at either 44.1k or 48k and use 2x upsampling if needed. That way i dont get these frequencies.