Just a bit of guideline on bitrates:
128kbps is the typical bitrate for most songs, some being 192 as well. 64kbps is really the minimum you'd want to go for. This will convert the file size to approximately half of what it was. I'd only go for 64kbps if your phone supports 32 chords or more, as it tends to sound a bit iffy on 4,8,16 and 24 chord phones. If you have a 64 chord phone (maybe a Samsung), then you might just be able to go that bit lower. If you can help it, try to make 16kbps an absolute minimum, as this sounds truely awful. Hope this helps

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