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How do I convert MP3 Audio 6gb files into small size & better audio format

Dear Experts

I got 6 gb MP3 audo lecture of one person, I want to burn on CD to play in my car, MP3 will play in my car but first I want to make these audio files in smaller size files, so hardly I fit all in 1 or 2 audio CDs. Please let me know how can I make this possible.

Thanks
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vigilparikh
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Also keep in mind you have a 700 MB CD which is 5 734 400 kilobits
For 64kb/s at 44.100 kHz it would fit about 25 hours (5 734 400 kilobits / 64 kbit/s = 89600 seconds => 24.8 hrs)
if you convert at 32 kbit/s you would get double the time (about 48hrs) but it would degrade the audio quality a lot.

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☠ MASQ ☠

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hey guys

I think most of the above questions would help me. I will give a go for each reply and see which helps me to reduce the size of current mp3 files.

Masqueraid,
I have attached the image of one of the folder of my audio files I got.. Please have a look
Do you know what bitrate would be the good. not too high not too low. Please advise User generated image
Note:

I just played one of the above track  ' 01 track' , it shows me that it will play for 27 min and 33 seconds.
So I hope if you can find wht bitrate its on.
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☠ MASQ ☠

My mistake, I thought this was a single 6Gb file!

Looks like your current compression settings are about 128kbps
With a 22050 Sample rate and 16 bit word length

If you change to around an 80kbps (good quality spoken word) compression Then you can reduce the file size by about a third (down to 2GB overall) converting to 64kbps would halve the file size but you'd start to notice the quality deteriorate and by the time you've reduced the bitrate to 32kbps, as said above it would be possible to hear the voice but it will start to get clipped (like listening to a voice on a telephone).

Reducing to 64 or 80kbps would mean, if you divided the files equally between each CD, that you could just about get the whole set onto two disks.

There is inevitably a trade off with compression and quality so you really need to try re-encoding one of your tracks and seeing what bitrate is the smallest you find acceptable to listen to.

If you want to estimate file size this is a good calculator
http://www.theaudioarchive.com/TAA_Resources_File_Size.htm#Bit_Rate_Tutorial
If you were to change the sample rate to 22 050 kHz it would not make a change in size (it would if you had uncompressed files)

As MASQUERAID said above, go with 80, see how it suits you.

So at 128 you have about 12.4 hrs @ 44.100 kHz
at 96 you would have ~15.5 hrs
at 80 you have about ~17 hrs
at 64 you have twice at ~24.8 hrs

below that ... I would switch from MP3 to AAC
I for one found that listening to some podcasts at 32 kbps is not that bad.

A bit of counterpoint => your files are already recorded at 22khz and using a 128k bit rate.    Unless you dramatically reduce the bit rate, you're not going to gain a huge amount of space -- recording at 80k would save a bit under 30% ... your total CD requirement would drop from about 9 to 6 or 7.

HOWEVER ... the quality will be notably degraded.    Recording an MP3 from one bitrate to another causes more loss than you would get if you encoded the same material at the new bit rate from its uncompressed original -- the encoding algorithms simply don't have as much data to work with.    Before you decide to do this for the entire colleciton, try a couple and be sure you're happy with the result.    Since this is just voice, you may be fine with it -- but be sure to listen to a few minutes worth before deciding.

Also, check your car's audio features -- many newer cars have USB inputs that you can connect a USB flash drive or external hard drive to ... if that's the case you could simply put all of the files on a single flash drive.    Some also support DVDs -- you could then burn the entire collection of files to a single dual layer DVD.
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Just pickup a small 8gb usb mp3 player with a small radio , its the easiest.
Just pickup a small 8gb usb mp3 player with a small radio , its the easiest.
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Guys

Thanks for your suggestions, it make me understand most of the things which I had questions, I have tried foobar but it didn't reduce the file size at all , it merged all files into one when I select that option. For mp3 it asked for lame which I provided by downloading from Rarewares , then I tried to convert to AAC but it again asking for command line encoder, what I need to do now . Please adivse
Please see the attached file to see difference five files and the one i tried usign foobar.

Snurker

thanks for suggesting mp3 joinner/splitter.
audioimage.bmp
Hi Guys

Please advise if there is any more suggestions?
Only I had valuable info. but not really it helped to reduce the size of the files straight away. but i am happy to give points to all.