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charliemouse
04-09-2007, 06:34 PM
Hi,
Is there a plan to restore the 11.5 functionality of being able to select maximum and minimum bitrates for mp3 (left right click on sliders) rather than using quality setting?

This was mentioned amongst other problems by a user in this thread,
http://forum.dbpoweramp.com/showthread.php?t=12115
..but only the use of command line was suggested. Any other ways to do this?

I'm a bit confused as to why it was removed?

thanks

charliemouse
04-09-2007, 07:07 PM
Further to that question, possibly broadening it:

A few test with the various VBR settings find *much* more variation in file size than using the old VBR with min/max settings. Variable 128-160 tended to result in all at just below 160.

The new settings at V4 which is supposedly an average of 160, seem to result in just about everything being below 160, but much more variability between files. Some are even below 128 - simple acoustic seemingly the lowest, classical fairly high, and electronic variable between 128 and 165.

I'm wondering if the -new setting gives byte-for-byte more sound quality than the old one? I don't have a requirement for specific sizes, as some do, but I used to work off principal that encoder could have no more than 160, but it might as well drop to 128 if it didn't need that.

Advice on that also appreciated.

PS Great V12.1 reference certainly resolves all WMa-MP3 issues for me :)

Deano
04-10-2007, 05:15 AM
LAME quality settings make sense for VBR mp3 files. LAME allocates bits based on QUALITY and not a minimum bitrate requirement. LAME's bitrate setting is incredibly intelligent and does a very good job, it goes low if it feels the complexity of the music is low and higher than when needed. Just because the encoder bitrate goes lower, does not mean the audible quality of the file is any lower. In fact, it is liable to be better because higher bitrates will be used in the sections that require it. The bitrate noted is purely "average" and no more than a guideline.

I don't see why hitting a bitrate target it important to you, if it is surely ABR is going to be more useful to you rather than a quality based VBR setting?

bhoar
04-10-2007, 01:20 PM
In this case if you are concerned, just bump up a quality setting or two. It'll probably end up being overkill, but it'll make you worry less about having to rerip. But the truth is that recent LAME builds have become very good at getting nearly the best quality/filesize ratio using the presets.

LAME is limited by the constraints of the (aging) MP3 standard, however: at some point the law of diminishing returns will provide a rather steep slope against any further improvement. This is one reason people who have multiple-codec players are tending to move to AAC. The standard is more mature: it can give either better subjective quality at similar bitrates (though certain bitrate "bands" show the most subjective improvement while others show very little), or give smaller filesize at the same apparent subjective quality level.

-brendan

charliemouse
04-10-2007, 06:23 PM
OK, thanks for comments. Yes, I'll probably just stick with VBR at a certain quality - I've no worries about having to re-rip: I keep everything as flac files, I just keep one drive for WMA / MP3 versions too so I can copy stuff to my player, and habbit led me to keep using min/max bitrate settings for MP3s. I'll go with the quality setting instead.
I'm still unsure as to why feature was removed, but no worries.