Question on encoding for iPod

So I have decided to encode a bunch of new stuff for my iPod, wiping out the lossless 24 bit stuff I had on it. I listen in the car, and I doubt I can hear the difference in that environment, and, even if
I could, I want to fit more songs on it. I have 160gb, so I should fit a lot.

My question is what kind of file is best - constant bit rate or variable bit rate? I will be using DB Poweramp to rip the CD's to Apple Lossy (highest bit rate allowed).

I also have some high-res stuff, like the Led Zeppelin material from the deluxe editions. My question is this - should I use the 24 bit files to encode to Apple lossy, or the CD's? Which would be the better source? Or does it not matter at all?

 

Well if you're using Apple Lossy then I would go with 256AAC VBR. They'll sound great in the car.

 

I also have a 160GB iPod. I used to put as hi-res a file as I could fit on my iPod, but I was running out of room quickly. I recently decided that 256 AAC (like @BayouTiger recommended above) is perfectly suited for my portable listening needs. They do sound perfectly fine in the car, which is where I do a lot of listening with my iPod.

There is a setting you can put on your iPod while it is connected to iTunes that automatically converts your music as you drag it to your iPod. It does not touch the files in your library. So, if I dragged a 16/44.1 lossless file to my iPod, my iPod would get a 256 AAC file, while my iTunes library would still have the untouched lossless file with no duplication.

 

I would also use 256kbps VBR AAC as it's fairly transparent imo.

As for the high-res stuff, I would use the best mastering as the source. Essentially whatever source sounds the best to you, use that one.

 

I might also note that if you're computer is pretty powerful, you may find the conversion pretty invisible as it some cases the PC can transcode the file a move the much smaller file across the iPod's USB2 connection faster than it can move the much larger file.

 

Thanks, guys. I will try a test using the 24/96 Zep files vs. the CD versions. The CD's would be easier, but whatever sounds best.

I assumed that the dither the record company used for the hi res to CD transfer would probably be better than what I have at home. Maybe not...

 

Like supermd said, if the high-res (or lossy) files are already in your library, just use the convert-on-the-fly option.

 

If you have 160 GB available to you, go with at least 320 AAC.
But, with that much space, why not go with Apple Lossless instead?

 

I used Apple Lossless when I had everything at 24/48. But I do a ton of driving, and it seems I am always wishing I had different stuff on there to listen to. I figure AAC will keep me entertained for a while...

 

Like I said, if you have 160 GB, you can afford to continue to use Apple Lossless.
When you use iTunes to rip CD's to ALAC it automatically adjusts the bit rate for each song to keep the file size small as possible while keeping sound quality.

 

AAC is just fine for the car IMO.

 

The only drawback to converting on-the-fly is that syncing takes much longer.