Resampling

[Bhaveshpa]

What is Resampler cutoff frequency ratio? It is set on 97% by default, should i change it?

[Fitzian]

cutoff # : specifies the filter cutoff frequency in terms of fraction of frequency bandwidth, also know as the Nyquist frequency. If upsampling, then this is the fraction of the original signal that should go through. If downsampling, this is the fraction of the signal left after downsampling.

SoX documentation recommends default value of 0.95 (95%).

[Bhaveshpa]

Most of my songs are being upsampled at 96khz so should I go with 99%?

[Fitzian]

2 hours ago, Bhaveshpa said:

Most of my songs are being upsampled at 96khz so should I go with 99%?

Doing that goes against the recommendation of SoX's developers, but I won't stop you.

[Bhaveshpa]

Can u provide link of the article?

[MotleyG]

22 hours ago, Bhaveshpa said:

Most of my songs are being upsampled at 96khz so should I go with 99%?

You can simply try this on your device. If you don't hear any difference or have any other issues, then you can keep it as high as you want. But I don't think this is really something that will make an audible difference for you - just a hardware/battery usage increase.

[Bhaveshpa]

Hmm

[Fitzian]

1 hour ago, Bhaveshpa said:

Can u provide link of the article?

5. What are the best 'rate' settings to resample a file and retain the highest quality?

Resampling is a series of compromises so there's no one true answer for all situations, but the following rules of thumb should cover most people's needs for 99% of the time:

 

• Phase setting: if resampling to < 40k, use intermediate phase (-I), otherwise use linear phase (-L, or don't specify; linear phase is the default).
   
• Quality setting: if resampling (or changing speed, as it amounts to the same thing) at/to > 16 bit depth (i.e. most commonly 24-bit), use VHQ (-v), otherwise, use HQ (-h, or don't specify).
   
• Bandwidth setting: don't change from the default setting (95%).
   
• If you're mastering to 16-bit, you also need to add 'dither' (and in most cases noise-shaping) after the rate.

~Link~

 

Reference is made to settings we do not have access to in Poweramp, but the one we do have is bandwidth (and dither). I would presume it is using parameters equivalent to VHQ and linear phase (but we just don't have options to change these, and we honestly don't need them).

Edited October 19, 2022 by Fitzian

[Bhaveshpa]

Are the quality and phase settings available on pc only?

[Fitzian]

5 minutes ago, Bhaveshpa said:

Are the quality and phase settings available on pc only?

these are command-line like settings on PC, yeah. you can also see these with the SoX foobar2000 component. I don't know if those options need to be implemented for mobile use, it's safe to assume the proper options are set internally in Poweramp.

Edited October 19, 2022 by Fitzian

[░▒▓█ クリス █▓▒░]

14 hours ago, Fitzian said:

5. What are the best 'rate' settings to resample a file and retain the highest quality?

 

•  
• Bandwidth setting: don't change from the default setting (95%).

~Link~

why is Poweramps default setting 97% then? 🤔

[andrewilley]

8 minutes ago, ░▒▓█ クリス █▓▒░ said:

why is Poweramps default setting 97% then? 🤔

That's what the developer decided upon, presumably as the best compromise for various scenarios. Feel free to adjust to anything you like though, that's why it's a setting.

Andre