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Yull
Hello guys, first post here rolleyes.gif I want to know why -Y switch can't supress frequency higher than 16k??
It doesn't work!!
AtaqueEG
What compile are you using?
And don't just say "3.90.2" or "3.90.3", but be more specific, as there are some compiles designed to only encode in -aps (to avoid "experimentation" with switches, that could harm sound quality)

Go to Rarewares and try with a different compile.
Yull
I'm just using lame 3.90.3 and trying "--alt-preset standard -Y" ,but It supress some tweaks! not freq!
Thanks for the reply
dev0
-Y != lowpass
Yull
yes but this switch doesn't work!!
tigre
Are resulting files bit-identical with/without -Y (to check: same size? if yes decompress both and do a wave substraction or EAC wave compare)
dev0
Sorry, but I don't really understand your problem. Please give more accurate information on what you are trying to do, what commandline and lame compile you are using and if you are using any frontends.

dev0
AstralStorm
That switch does nearly nothing on music which has few and powerful transients (percussion)...

It doesn't suppress high frequencies! It only removes most of scalefactor band 21 (>16kHz),
which tends to bloat the bitrate (due to the lack of a scalefator).

To really remove frequencies >16kHz use --lowpass 16
/EDIT\ changed = to space \EDIT/

It probably does work, but is hard to notice with the type of music you compress (classical? jazz?).
Yull
Yeah I use "--alt-preset standard -Y"user posted image
JohnV
What exactly you mean with "does not work"? It does work.
If you mean that warning you get in your console, that's perfectly normal, it just says the meaning has changed. Actually imo that warning could be removed since the change happened soon 2 years ago or something..
Yull
Thanks biggrin.gif I didn't notice any difference with that switch!!
indybrett
It most certainly works. If you want to eliminate the transients, do this:

--alt-preset standard -Y --lowpass 16000

I actually use that command line for everything. I could probably just use the lowpass.
Yull
Good idea to supress some high frequencies, because I think MP3 amplify them. What about "--alt-preset cbr 192 -Y --lowpass 16" for compatibility?
indybrett
The reason for using -Y is to prevent the "bitrate bloat" that occurs with VBR encoding high frequencies. If you are using CBR, the bitrate will never change, so there is no reason to use the -Y switch.

If I'm wrong about this, someone please correct me.
Yull
Right!! I am testing this : "--alt-preset cbr 192 --lowpass 17.3" The High frequencies are not super-amplified!!
ErikS
Normally high frequencies shouldn't be amplified also without the lowpass filter. Are you using some sort of equaliser when playing your mp3s?
AstralStorm
QUOTE(Yull @ Jun 29 2003 - 05:31 PM)
Right!! I am testing this : "--alt-preset cbr 192 --lowpass 17.3" The High frequencies are not super-amplified!!

--lowpass uses only integer numbers, so you should rather use 17.

And better use --alt-preset 192, which should give higher quality
or even --alt-preset standard (highest quality of the three),
which has similar bitrate on the average.
Yull
Yes I use CBR because of compatibility and speed. Love VBR but the difference is not so big with CBR for the quality. But in some case I use --alt-preset standard for encoding!
MP3 is a compression format, alt-preset are designed for being the best switch for encoding, but it will never reach the CD quality!! CBR is good enough.. B)
veryhappyjk
I've played very very much with -Y switch.

In some cases (especially metal music), high freqs need a bunch of bits (i'm talking of 20 kbit/s difference) even if the lowpass keeps 500 hz after 16khz (-->16,5 khz lowpass).

personally speaking, i do not hear difference between 16 khz LP and 18 khz LP, but some people can, so i do not encode in mp3, it would wast too much space.

byebye, saverio m.
Old Nick
QUOTE
In some cases (especially metal music), high freqs need a bunch of bits (i'm talking of 20 kbit/s difference)


I'd say the difference is usually around 40. Sometimes as high as 80-100.
High Fidelity
The -Y switch seems to have no effect on the "3.90.3 Modified" version in combination with the medium preset.

That can mainly have three reasons:
* -Y is already default in the medium preset
* the switch has no effect in combination with the medium preset maybe because of an lowpass ?
* the switch is not mapped for medium

What´s true?

I already searched the board for an explanation of the medium preset, but was just able to find the parameters (+ Dibroms mystical internal tweaks of course biggrin.gif ) what --alt -preset standard stands for.
Does anybody know...?
tigre
QUOTE(High Fidelity @ Jun 30 2003 - 08:18 AM)
I already searched the board for an explanation of the medium preset, but was just able to find the parameters (+ Dibroms mystical internal tweaks of course  biggrin.gif ) what --alt -preset standard  stands for.
Does anybody know...?

add --verbose switch to get information about many settings used. This might also help to find out what's the deal with -Y and --preset medium.

QUOTE(AstralStorm @ Jun 29 2003 - 08:47 AM)
--lowpass uses only integer numbers, <snip>

That's new to me. When has this been changed?
AstralStorm
Sorry, LAME does accept floating-point arguments, but 17.3 is exactly same as 17.
ErikS
QUOTE(AstralStorm @ Jun 30 2003 - 06:50 PM)
Sorry, LAME does accept floating-point arguments, but 17.3 is exactly same as 17.

So if you need more control write 17.3 (kHz) as 17300 (Hz) instead. Then it will work.
AstralStorm
No, it won't smile.gif
LAME always uses polyphase lowpass with varying lowpass frequency.
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