Hello,

I use Lame v3.97 and -V 2 --vbr-new switch. _Some_ of resulting files have bitrate of around 124 and during playback bitrate drops to 96 kbps at some places! Is it normal behavior? Does the encoder consider some tracks too simple to encode in high quality? I encode from original CDs that have high quality and no scratches. EAC says no errors. I have to use the -b 160 switch all the time to be sure I get good quality rips. Such files then have only 160 kbps and don't go higher. Other tracks go higher as usual, but don't drop below 160. It's just strange how selective Lame is. Do any of you have similar experience? I used 3.98b6 to test, but the files were just the same bitrate ~130 kbps.

Thanks for your answers!

First off, take away the -b 160 command as that alters the way Lame encodes. It should encode every frame at 160kbps or above but it also makes the encoder less VBR and more like ABR at 160 meaning that more frames will be encoded at 160kbps when they should be at a higher bitrate.

It is completely normal for the bitrate to drop to 128kbps or even 32kbps, this is called being VBR. Make sure that you can properly ABX the files first. If you can't ABX them then don't worry about it. Too many people focus on the actual bitrate or the way a frequency graph looks rather than the way music sounds. So leave your command at -V 2 --vbr-new. More than likely the -b 160 is a thought in your head and not something that you will actually be able to hear.

Hello Louck,

the resulting bitrate mainly depends on the kind of music you are encoding. If you, for example, encode an Eric Satie CD using -V2, the bitrate will reach the levels you describe here.
Would you tell us what music this was?

This happens usually when you encode CDs with "mono" tracks (both channels have the same information), like early Beatles CDs and even their "1" album (first three tacks)

Bitrate isn't quality.

With CBR, bitrate is constant, but quality can vary.
With VBR, the idea is to make the quality constant, but to let bitrate vary.

effectively, silent parts could reach down to 32kbps... like the people said above, VBR is the use of several bitrate to store different kinds of samples, some samples may require nothing, other samples may require even more than 320 kbps.

I encoded The Rolling Stones CD and some songs like the famous "I can't get no satisfaction" and number of others had bitrate of 96-128 during playback, not during silence as you suggested. The same thing happened to most of Aretha Franklin. The files sound perfectly, but as you said, it's in my head: <192 kbps is bad. And I would otherwise delete any file of 128 kbps on my hard drive, not to say 126 kbps as with Rolling Stones. But it's my encode with standard preset! I was a bit confused.

Thanks for so many answers. I think I shall keep the encoded files.

On near mono or mono signals this low bitrate is expected. At -V3 I have a PJ Harvey track @ 116 k , yet other stuff like REM, VAST uses up to 200 k

A wise decision, Louck.

Classical musical CD's can have this effect I think as there are many almost silent parts in most recordings, that means I expect the encoder lowers bitrates when this occurs.

For LAME, only <92 kbps is probably bad. ... And >128 kbps is un-ABXable for me.

"Some_ of resulting files have bitrate of around 124 and during playback bitrate drops to 96 kbps at some places! Is it normal behavior?"

Yes it very often happens to me with old material that is mono or near mono. No it's not a bug, that's what it's supposed to do when the material is very easy to encode. Mono tracks only contain somewhere near half the information so it's to be expected.