Bit rate question
I wish to get the most compression of recorded music practical on the 256 GB iPod I expect to obtain soon. I would like to sync my entire 415GB iTunes library to the iPod and have room for additional downloads. I am using 192kbps mp3 compression in my iTunes library and 128kbps in my current 160GB iPod Classic. (I previously used 320 kbps in iTunes but then decided I needed more "room" and did a "do-over" of the entire library. It still works the same for my poor ears)
My hearing is poor and even with digital hearing aids it is down 60 db at 5KHz. The speakers I use with my iPod (via bluetooth) are not great, I use the iPod & speakers for background music in a store where I work part time. When I want to listen to music at home I have several other options and I would not use my iPod "on the go" other than to plug it into the car radio-something I only tried once in 8 years of iPod ownership.
So I wonder if I can get away with 64 kbps compression for my purposes. What will I lose within my hearing capability?
If you listen to a lot of violin music, it will sound very "glassy" at low bitrates. I wouldn't recommend it.
What is "glassy?"
Its probably a subjective term.
With a 256 GB Ipod you will be able to put hundreds of CDs on it using Apple Lossless Compression (I use FLAC on my non-apple devices). I can hear the difference between 320Kb/s and lossless, and you probably can too. Lossless is the way to go.
At high compression rates, I find that a violin starts to have a sort of sharp, hollow edge to the sound, as if the string were glass that were being scraped. That's what I meant.
Thank you all for your inputs. I don't know what is clipped when mp3 files are compressed. With too much compression I might miss very crisp transients - I don't know, but because of my hearing deficit I am unable to appreciate musical sounds above about 3,000 Hz and I really resent the dynamic range available on CDs because if I can hear orchestral pp or ppp, I cannot tolerate ff - and my wife definitely can't..
Try it and decide for yourself. I would suspect you will hear some type of degredation
Jason, mp3 fixed bit rate compression is far more intelligent than just making a smaller frequency range. Its not just in high and low frequencys different when you choose a lower bitrate. That would be digital stone age.
For mp3, 128kbps is the rate at which people typically begin to notice a difference between the compressed and uncompressed stream. Smaller stream rates will work for normal speech.
Aac is about the same in terms of result, slightly more options but basically the same idea. In the usual rates you wont be able to call one better or worse. Is it really closed apple stuff? I thought they just jumped on it and helped coding, but I didnt do research on that.
Newer compression formats like Ogg Vorbis and AAC will sound comparatively better than MP3 at the same bitrate. I don't recommend compressing anything below 128 kbps j-stereo though. Especially for classical music, the compression artifacts stick out horribly.
Cancel the order and buy FiiO X7 or X5.
@ Rocky I agree, FLAC is one of the best types of compression to use if you must compress. 256-320 mp3 is passable 128 is not very good. 64 mp3 is horrible no matter what the program material is.
I went through this exercise some years ago when my ears were better than they are now. I recorded a few minutes of symphonic, chamber and solo violin music from good quality CDs as wav files at 44kHz sampling rate, and saved them successively as 320, 256, 224, 192, 160, 128 mp3 (I didn't have FLAC). Then I spent an hour listening to and comparing the recordings. I couldn't tell the difference between 320 and 256; 256 v 224 was just about discernible with very careful listening, but certainly not off-putting; 192 was starting to get noticeable, and 160 more so, but both were perhaps bearable for some kinds of music or music from radio; as for 128 - forget it except for spoken voice on radio.
Well, Trevor, it depends a lot on at least 3 factors:
Rocky, I should have mentioned that I used, and still use, Sennheiser HD205 headphones - perhaps not Bose quality, but certainly not bad.