[fearless]

Do -alt preset standard VBR files sound about the same as 192 kbps ABR files? Does one sound better than the other?

 

[egglick]

That all depends what quality VBR you're using. I typically use a constant bitrate, because I don't trust that the VBR encoder will always choose the correct bitrate for a given section of audio. I'd rather have my bitrate be too high when it doesn't really need it, than too low when it does.

I'm by no means an audio encoding expert, but those are just my feelings.

 

[fearless]

I currently use -alt preset standard and -alt preset extreme for certain music. Wondering if there would be any advantages, eg. better sound quality, smaller file space to switching to ABR.

 

[blessingx]

It does depend as if you have a VBR scheme that hits consistently below 192, it's unlikely a ABR 192 is going to sound worse. That said, I'd disagree with egglick in that -aps will in all likelihood will average above 192, so by the numbers should sound better, besides I'm not sure why you'd trust all the other aspects of lossly encoding (perceptual weighting, joint stereo, high/low pass filtering, etc.) and not trust this (assuming you're going below 320 kbps). Unless you're trying to find a consistent file size or encoding very low bitrates (where CBR may be best) VBR is the way to go. The sound improvement on especially complex passages should be there and although it probably doesn't warrant re-encoding albums, I'd definitely use it going forward. As the guys over at Hydrogen say: VBR>ABR>CBR... in most cases.

EDIT: Quote:

Originally Posted by fearless I currently use -alt preset standard and -alt preset extreme for certain music. Wondering if there would be any advantages, eg. better sound quality, smaller file space to switching to ABR.

No you won't get smaller file sizes and better quality going ABR. You may get one or the other (256 ABR may sound better than ~200 VBR), but not both. You may prefer moving to a new codec (Ogg Vorbis or AAC) at similar bitrates, but again it depends on which artifacts bother you most. I say stick with -aps or -api if you're going MP3 or have a very small flash player and need the space (with doesn't support AAC or have battery issues with Ogg).

 

[fearless]

I think I'm going to stick to -aps, I can't see much benefit of -alt preset extreme with my current setup nor ABR. -Aps sounds good to me and seems like a good comprimise between filespace and quality.

I have another question, how much does the fast option on -aps degrade the sound quality? Is it very noticeable?

 

[electrosoccertux]

Quote:

Originally Posted by fearless I think I'm going to stick to -aps, I can't see much benefit of -alt preset extreme with my current setup nor ABR. -Aps sounds good to me and seems like a good comprimise between filespace and quality. I have another question, how much does the fast option on -aps degrade the sound quality? Is it very noticeable?

Well you know if you use CDex you can rip tons of CD's as wav's to your hard drive, then hit encode as mp3 at night and leave your computer to do its stuff. I'd rather do that than risk sound quality. Unless you have a super-cheapo computer, you should be fine, and even then, the worst that would likely happen is your PSU go out (easy to replace).

 

[blessingx]

Quote:

Originally Posted by fearless I have another question, how much does the fast option on -aps degrade the sound quality? Is it very noticeable?

Using the 'fast' tag it's more "potential quality loss" so it's far from substantial and may or may not be noticeable. Depending on your LAME version it may even be recommended. I use it all the time for MP3 (though mostly using AAC now myself).

 

[fearless]

I do use CDex 1.51 and I probably won't use the fast option. The lame version says it's 1.30, engine 3.92 MMX. If I were using EAC more often I might consider it though.

 

[Febs]

If you upgrade to the 3.97b2 version of LAME, you will notice a huge improvement in encoding speed without quality loss.

 

[egglick]

Quote:

Originally Posted by blessingx It does depend as if you have a VBR scheme that hits consistently below 192, it's unlikely a ABR 192 is going to sound worse. That said, I'd disagree with egglick in that -aps will in all likelihood will average above 192, so by the numbers should sound better, besides I'm not sure why you'd trust all the other aspects of lossly encoding (perceptual weighting, joint stereo, high/low pass filtering, etc.) and not trust this (assuming you're going below 320 kbps).

I'm not familiar with the particular VBR switches you guys are discussing. As I said, it all depends on the quality of VBR you're using versus the quality of CBR. If you're using 256/320kbps CBR files, it's hard to argue that a VBR file even over the same ranges is going to sound "better". VBR may be more efficient in filesize, but you still run the risk of having too low a bitrate in a particular passage. Using a high bitrate CBR prevents this from happening, at the expense of often having too high a bitrate in many low quality passages (and thus having a larger overall file). Sound quality wise, the latter is perferable.

You bring up a good point about the other aspects of lossy encoding, which is why I try to keep those things to a minimum by not introducing another variable. I also don't use joint stereo.

 

[Febs]

Quote:

Originally Posted by egglick Using a high bitrate CBR prevents this from happening, at the expense of often having too high a bitrate in many low quality passages (and thus having a larger overall file). Sound quality wise, the latter is perferable.

On the other hand, CBR runs the risk of not having enough bits for passages that require higher quality. By using CBR, you are basically stealing bits from passages that require higher quality and forcing the encoder to use them in passages that don't require a high bitrate. I strongly disagree that this is preferable to using a VBR file. VBR encoders provide substantially higher quality for a particular filesize than CBR.

Quote:

You bring up a good point about the other aspects of lossy encoding, which is why I try to keep those things to a minimum by not introducing another variable. I also don't use joint stereo.

Again, if you only use L/R stereo and you don't use joint stereo (which at higher bitrates should more accurately be called Mid/Side stereo) where it is appropriate, you are forcing the encoder to use a less efficient encoding method than it would otherwise be able to use. This can only result in a lower quality file for a particular file size than what the encoder is capable of.

Why use a lossy encoder at all if you're just going to cripple the encoder's ability to produce the highest quality for a particular file size? Using a lossy encoder means that you are trusting the encoder to alter your file in a way that reduces its size but does not result in a perceptible change to the sound. If you go that far, there's no reason to reduce the encoder's functionality.

 

[fearless]

Quote:

Originally Posted by Febs If you upgrade to the 3.97b2 version of LAME, you will notice a huge improvement in encoding speed without quality loss.

I might have to check that out, maybe use it with EAC.

One thing I don't like about -aps is how silence is recorded as 128 kbps, it seems like such a waste.

 

[egglick]

Quote:

Originally Posted by Febs On the other hand, CBR runs the risk of not having enough bits for passages that require higher quality. By using CBR, you are basically stealing bits from passages that require higher quality and forcing the encoder to use them in passages that don't require a high bitrate.... Again, if you only use L/R stereo and you don't use joint stereo (which at higher bitrates should more accurately be called Mid/Side stereo) where it is appropriate, you are forcing the encoder to use a less efficient encoding method than it would otherwise be able to use. This can only result in a lower quality file for a particular file size than what the encoder is capable of.

Good points which I will take into consideration. For a particular file size, yes VBR would be higher quality, but I wasn't assuming equal file size. At lower bitrates, VBR may very well sound better, but you guys seem to discard the fact that I'm using high bitrate CBR (256/320) for comparison. Would a VBR file which ranges from 160-320kbps sound better than a CBR encoded at 256?? In my mind it's hard to say. Said VBR file might only hit 320kbps on a couple of occasions, and typically reside between 192 and 224kbps.

As I said, I'm not an audio encoding expert. I'm also very interested in getting into lossless compression, just haven't had the time to research it as of yet.

 

[fearless]

I've got a question on EAC. Under the Waveform tab under compression options, if I choose Lame -aps will any of the settings I make in the LAME.dll tab do anything to change the files, or is it overridden by the -aps settings?

 

[Febs]

Quote:

Originally Posted by egglick Would a VBR file which ranges from 160-320kbps sound better than a CBR encoded at 256?? In my mind it's hard to say.

See, I think of it as the converse. A CBR file at 256 can never contain a frame higher than 256, even if the encoding would benefit from a higher bitrate.

If you have a chance, use LAME's command line encoder to encode a file at --alt-preset standard (which is known in the 3.97b2 version as -V 2). As LAME encodes the file, it keeps a histogram showing the bitrates that are used in the file. You'd probably be surprised by how many frames are encoded at 320kbps.