Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

[Kyin3]

Okay so I'm trying to compress some mp3s I have (someone once told me I can get most mp3s to half the size it currently is by compressing them), but I have too many features I don't know what they do!

So my question is after choosing the 96 bit rate option what do the rest of the options determin?

for example what is frequency?
and Channels?
and what is the option preserve ID tags?
in power pack option what are conversion runs?
lastly I know some of my mp3s has album art display if viewed with some programs can dbpoweramp remove all this excess album arts and lyrics that take up space within the mp?


basicly I'm intrested in what will give me the smallest compression w/o having to sacrifice anything lower than a 96 bit rate sound quaility.
thanx

[Spoon]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

Set everything to [as source] for the best results. ID Tags are information about artist, etc, you want that.

[Kyin3]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

after I set As Source what do I do with the other options?
and when u mean best you mean like what?

and how do I get rid of the album arts and lyrics within the mp3?

and do id tags take up space?

[ChristinaS]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

No lyrics or album art will be in the dMC converted mp3's as they are not supported, not part of standard tags.

The id tags only have title of song, artist, album. I think the space will be there just the same whether you preserve them or not. In any case that is very small compared to the overall size of the audio file.


The frequency setting does not really affect the file size, so leave that "as source". However at very low bitrates it may sound betetr with a lower frequency setting. Don't bother changing that yet, until you have seen what you get by leaving it "as source".

The bitrate is what affects the resulting file size (and the audio quality) so if you want a smaller file, you have to set the bitrate to a smaller value than what it is currently.

The space savings are really proportional to the bitrate used.

Channels refers to whether it is mono or stereo. Stereo, all other things being the same, takes up twice the space of mono. Joint stereo is a good compromise, because it's basically like mono but with extra information so it can recreate the stereo separation - thus it will take up less space then actual stereo, but somewhat more than mono - it depends on how different the two channels really are actually.

[Kyin3]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

^ wow your awesome!

Okay so in advance options you get "Encoding:" in which you can choose constant, average, or vairable. What will they affect and whats the best for smaller compression? (not to mention the bar next to it and the bit reservior box)


And whats the deal with "Set Bits" and "Write CRC Checksums" at the bottom?


lastly how will the Preset affect the size and audio quality?

[ChristinaS]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

In the Set Bits you can implement your own copyright protection of sorts. I wouldn't use that. Keep it on Original.

I prefer not to use presets so I keep the quality on No preset. Presets override whatever else you have selected in the window before. There's an explanation somewhere of what each preset is equivalent to if you were to pick the options manually.

Constant bit rate allows accurate prediction of the file size. Average and Variable bitrates don't. Variable bitrate may provide a better audio experience, but it could result in a larger file (or smaller) depending on the complexity of the audio content itself. This is my interpretation of what I understand VBR does: some passages may be encoded at low bitrate (e.g. quieter parts or plain speech maybe) while others of a more complex nature (e.g. multi-instrument passages covering a wide spectrum of frequencies) will be at a higher bitrate to enhance the audio quality. Some portable devices may not handle VBR though. And as I said you cannot accurately predict the file size. Not sure how to describe average bitrate.

I have to recommend you experiment with VBR and CBR yourself, also select different bitrates and see what you consider acceptable audio-wise and filesize-wise. Remember, keep it all on No Preset - at least until you figure out which actual settings you'd like to use - and then see which preset may match that. depending on the quality of the file you are starting out with you may compress more or less until you find the audio quality unacceptable.

The last thing, Write CRC checksums - I keep it checked, as it is useful to establish if a file is corrupted. What this does is perform a particular computation using some bits in the file and writes out the result. If the file becomes corrupted, the value in the area used to store the result of the checksum will not match what is in the rest of the file, indicating probable corruption.

Keep in mind a PCM wav 16-bit, 44.1KHz, 2-channel stereo (i.e. the same as an audio cd track) occupies about 10MB of space for 1 minute of audio. That's the yardstick you use to compare all compression.

The space a file takes is really proportional to the bitrate used, no matter if it is mp3 or wma or other formats. At 128kbps, CBR, 2-channel stereo, you have about 1MB per minute of audio. At 256kbps it's twice as big. At 64kbps it's half the size. And so on. There is little variation simply due to the format, it's really all in the settings.

[NoOne]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

Don't forget as well, 96kbps for music is almost unbearable to listen to by most people. If size is the only thing you care about then fine, but if you want decent audio quality, I suggest at least 192kbps (and some will say the minimum should be higher than that).

Experimenting for yourself is the best way.

[ChristinaS]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

Unless you specifically want to have your files as mp3, wma offers higher audio quality at a lower bitrate, thus resulting in smaller file sizes.

You never did mention what quality your current mp3 are, i.e what bitrate.

Re-encoding mp3 to any other lossy format, no matter what settings, will result is a somewhat worse audio quality than if you had started out with the original wav (or audio cd track) and encoded to that new lossy format in the first place. Just so you know, but it cannot be helped. You cannot ever "improve" quality by encoding to formats with higher settings, so don't bother.

The thing is if you want to encode from whatever current bitrate your mp3's have to a lower bitrate, and if you can afford it, then encode to wma at the lower bitrate, rather than mp3 at that lower bitrate. You will have space savings and preserve a bit more of the audio quality. But best is to test it yourself, as all comrpessions may give strange results based on the quality of the audio file you start out with.

Don't delete your originals no matter what. If you have to make room on your hd, burn them to cd at least before deleting them.

[Kyin3]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

yeah thanx I guess I will try them

but yeah my mp3s are of 128kbps-256kbps they vary most are in the 196s.

But I tried 96kbps compression and it didn't seem to have any quaility change

[Kyin3]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

Hey what is DSP effects?

[xoas]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

DSP effects come with the Power Pack. A brief description, from Spoon is:

DSP is short for Digital Signal Processing, think of a DSP effect as altering the sound in some fashion (for example you can alter the treble on a HiFi, DSP effects can do this too with a Graphic Equalizer DSP Effect). dMC comes with advanced and varied DSP effects, obviously you will not want to run them all, be selective thinking of what final effect you are trying to achieve. DSP effects are listed and explained alphabetically and later examples of using multiple DSP effects are given.

This quote and other information can be accessed through your Help files if you go Start>All Programs>dBpowerAMP Music Converter>Help>dBBpowerAMP Music Converter Help find the section re:Power Pack and click on DSP Effects. Here you will find some more detailed information including brief descriptions of each effect.

Best wishes,
Bill

[Kyin3]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

DSP effects come with the Power Pack. A brief description, from Spoon is:


This quote and other information can be accessed through your Help files if you go Start>All Programs>dBpowerAMP Music Converter>Help>dBBpowerAMP Music Converter Help find the section re:Power Pack and click on DSP Effects. Here you will find some more detailed information including brief descriptions of each effect.

Best wishes,
Bill

So pretty much if I leave it alone my mp3 will sound the same and in no way with lessen the quaility of the audio correct?
and if I do add some effects will it increase the mp3 size?

[LtData]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

Right, if you don't use DSP effects, they won't change your file. As for the size, it depends on the Effect used. Some can cut part of the file off, some can strip vocals, some increase the file to 24-bit, etc.

[Kyin3]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

okay last question ty for all your help much appriciated
the presets in the advance option are pretty much auto config right? if you want to config the settings your self (e.g. bitrates frequency etc) you leave the preset at no preset?

[xoas]

Re: Compressing Mp3s into 96 Bit Rate, but what do I do with the other options?

The simple answer is yes.
The slightly more complicated answer is that if you are comfortable using a command line interface you can tweak even more with the Lame (CLI) codec.
But if, like me, you are not comfortable using the command-line interface the simple answer will more than suffice.