HydrogenAudio

Lossy Audio Compression => MP3 => MP3 - Tech => Topic started by: rizukitomi on 2017-05-19 16:27:05

Title: iTunes MP3 highpass 10hz
Post by: rizukitomi on 2017-05-19 16:27:05
Guys, Recently i've been messing around with iTunes, and i want to ask about one of all option in iTunes MP3 Encoder, "Filter frequency below 10hz", i don't want to mess with that option, since i never mess with lowpass and highpass, but could someone explain to me about this ? did this increase audio quality ? and what if i use it in LAME, since iTunes MP3 Encoder use it as general basis.

Thanks guys.
Title: Re: iTunes MP3 highpass 10hz
Post by: [JAZ] on 2017-05-19 18:27:18
I am assuming that the intended usage of that setting, since it is on encoding, is to kill any DC offset that the original audio might have.
Title: Re: iTunes MP3 highpass 10hz
Post by: rizukitomi on 2017-05-19 19:05:59
Thanks for the answer, and what about "smart encoding adjustments" option, for all i know, iTunes only have few options, so why there's "smart encoding adjustments" option ?, i can't really see the difference ? except for stereo separation, <200 kbps have joint stereo, and >200 kbps, other than that i don't know... well iTunes mp3 is not like lame, i can see it every time i encode audio because lame has CLI and iTunes not...

Did "smart encoding adjustments" change all settings that i set ? did that change the 10hz highpass value too, because when i see the support page on apple, it's only "smart encoding adjustments" is to maximize quality, that's all...
Title: Re: iTunes MP3 highpass 10hz
Post by: [JAZ] on 2017-05-20 00:47:40
I can't comment on that other button and it's been ages since I last used iTunes.
Title: Re: iTunes MP3 highpass 10hz
Post by: j7n on 2017-05-20 06:32:43
Killing DC offset on one file at a time is not necessarily safe. If the filter doesn't remember the history of the preceding audio, and resets at the beginning of a track, and there actually is DC or low frequency rumble preset, this will create a click. I don't know how iTunes does it, whether it processes the whole album at once.
Title: Re: iTunes MP3 highpass 10hz
Post by: rizukitomi on 2017-05-20 06:41:56
iTunes does it one file at a time, that's why i ask about it, and it seems like "highpass 10hz" is default option on iTunes MP3, because when i press "restore default settings" that option is checked, should i leave it or unchecked it ?