Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

[Max Dread]

Hi

I will be using VBR, but the quality slider I might vary depending on how much I like the album.

I could not find too much info about the Encoding Setting (Slow/Normal/Fast) and wondered if someone could explain the difference and which in my case would be best.

Many thanks

Max

[Max Dread]

Re: Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

Just to add a couple more things to this....

In Configuration I have the following settings:

- mp3 Decoder Output: 16 bit
- mp3 Decoder, Decode Errors: Ignore.

Should these be left as is? I will only be using DBPA to rip CDs. I've read the help fiule but still not sure whether to leave these as is or what the other options do....

Cheers

Max

[Spoon]

Re: Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

It is the different quality mode in Lame, set to slow if you want the best quality.

If only ripping to mp3 those decoder settings are not used.

[Max Dread]

Re: Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

It is the different quality mode in Lame, set to slow if you want the best quality.

OK, thanks. Does it effect file size at all? How much difference does it make to the time it takes to encode?

If only ripping to mp3 those decoder settings are not used.

OK, I'll leave them then. But just to clarify and be sure, I am ripping to FLAC and MP3 at the same time...? Out of interest, when are those settings relevant?

Cheers

Max

[Spoon]

Re: Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

Size should not change.

Those settings are for decoding mp3, if you convert from mp3.

[Max Dread]

Re: Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

Thought I would try some experiments.... This is what I found

SPEED
The speed to encode made no difference between Normal and Slow (High Quality). I checked three times and on each check it took the same amount of time to encode for both speeds. I tested with just one track at a time (each track varied from 4 to 6 minutes).
On the other hand, Fast (Low Quality) was quicker. For a 4 minute track, it encoded approx. 2.5 seconds quicker than the other two settings.

SIZE

Contrary to.......

Size should not change.

.....I found that whilst there was no difference between Normal and Slow, Fast DID produce smaller file sizes. For a single track (length 4:45), encoded to VBR -V2, I got the following results:

Slow and Normal: 6724KB
Fast: 5062KB

More interestingly, I did the same experiment on a track only 20 seconds shorter (4:25) and the results were far more different than I would expect for a 20 second difference:

Slow and Normal: 6471KB
Fast: 5948KB

Why would the longer track have a smaller file size in Fast? That is strange.....

Admittedly, this has become largely academic now because i think I will stick to SLOW all the way. But it would still be interesting to find out why this is happening. And it may help someone else out in the future.

Cheers

[Max Dread]

Re: Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

Any thoughts on these odd results guys? Cheers.

[garym]

Re: Which mp3 Encoding Setting to choose? Slow? Normal? Fast?

Any thoughts on these odd results guys? Cheers.

i suspect fast vs slow and normal is creating different sizes based on working "less hard" to do an optimum encoding to vbr mp3. A "better" encoding algorythm could make a file larger or smaller depending on certain factors. If you're really interested in this issue, I'd suggest running your experiment with about 20 tracks. Choose several different styles (loud songs, soft songs, "big" sounds of full band, solo instrument stuff, etc. I'd bet that the file size being more or less will be all over the place. Bottom line, a quality mp3 codec like lame is not simply trying to make the file smaller....it is trying to make the lossy file as transparent as possible as compared back to the lossless file.