Okay, some time ago I posted an entry about what MP3 player to get. There was some flak about my ideas on ripping music to place on your MP3 player, so I thought I would make an attempt at the end-all-be-all rip guide.ADHERER

In case you’re wondering, “ripping” MP3s (or other audio files) is the act of pulling the audio information off of a standard audio CD and creating compressed (or in some cases, uncompressed) audio files on your computer. This is a very common activity these days as practically no one has a computer that doesn’t use it for audio in some form or fashion. Herein, I will refer to tracks and songs, but you can do this with any audio, from books on CD to comedy albums to whatever your heart desires.

The quality at which you rip your audio depends on several factors:

1. Where you will listen to the audio
2. What type of audio it is
3. What compression format are you able to use?
4. How discerning is your ear?
5. How big is your DAP (Digital Audio Player)?
6. How much music do you want on your DAP?
7. Ego

Let’s explore these one-by-one. But first, let’s start with a base. Many of you will disagree with this starting point, but please, read to the end first. You may well get satisfaction.

Many audio rippers consider 128kbps (kilobits per second) to be so-called “near CD quality.” Without going down the road that says yes or no to that, let’s just agree to start there and see where it goes. Each of the above factors will raise or lower this number accordingly. So for now, let’s say we’re starting at 128kbps.

Where will you listen to this audio? This is a big thing. If you are going to be in a sound-proof room, with $1,000 headphones on your head plugged into a $5,000 stereo, then you will be able to hear every little imperfection, so you will probably want to rip at a higher bitrate. However, if you mainly take your DAP to a construction site, listen to it in your car, use an FM modulator, or use el-cheapo earphones, then the audio quality will suffer anyway, so you can go to a lower bitrate if you want. I probably wouldn’t go below 128kbps regardless, but you may wish to bump up to 256kbps or even to a lossless format if you are going to be in a very sound-proof area listening to this audio.

What type of audio is it? If you are listening to Brahms, Bach, and Beethoven, then you probably want to increase your bitrate as imperfections will be glaring in this type of audio. However, if you listen to Blink-182, Boston, and Breaking Benjamin, then the bands’ own distortion will not get any clearer at higher bitrates, so you may wish to stay at 128kbps or maybe even a smidge lower (depending on the other factors in this list). Furthermore, if it’s a standup comedy album or an audio book, then you can probably choose a lower bitrate, since spoken voice doesn’t command a lot of bits to sound acceptable. And if you are ripping a CD full of old radio broadcasts, then you may wish to drop the bitrate a tad since these tracks are already distorted anyway. And if you have mono tracks (instead of stereo) then you can drop the bitrate there as well, since a stereo track will have the bitrate divided between the left and right channels, but a mono track won’t.

What compression format are you able to use? iPods can play more than just MP3 formatted tracks. And many DAPs can play Windows’ WMA format. Both of these are touted to be the same quality as MP3 at half the bitrate. I wouldn’t go cutting the bitrate in half just yet, but if you are okay with 128kbps MP3s, then 96kbps WMAs or AACs (the Apple-preferred format) might be fine for you as well.

How discerning is your ear? If you are in the audio “biz” then you will probably be able to pick out imperfections far better than the average bear. If this is the case, then you may wish to increase your bitrate so that you don’t hear as many cringe-worthy niggles in your music. On the other hand, if you are like most of us and can’t really tell the difference, then you may wish to choose a lower bitrate.

How big is your DAP? This is where bitrate really becomes the issue. On your PC, where there is tons of free hard drive space, you may wish to rip everything at high bitrates, because there is plenty of room to grow. However, your portable player doesn’t have infinite space. If you have a 1GB player, then you can fit about 17 hours of 128kbps audio on it, give or take. That might seem like a lot, but you’d be surprised how fast audio can fill up a DAP as well as how much music you really want to take with you. If you go uncompressed, then you can fit about 1.5 CDs worth of music, or about 90 minutes, onto a 1GB player. Somewhere in the middle is the sweet spot, probably, but you have to make that call. If you have an 80GB iPod or a 120GB Zune, then you have plenty of space… unless you are going to suck up a lot of that with video. But that’s another topic for another day. My entire music collection is a tad over 21GB (that’s 21 Gigabytes), most of it at 128kbps (which was the standard in the Napster Heyday). I could probably play my entire collection from the start and die before it gets to the end. My iPod is 80GB, so I put everything on there. But my iPhone is only 8GB (and I keep a good deal of video on there) so I have to be more selective of what I put on that device. In the end, I could get more music on the iPhone if I rip at a lower bitrate.

How much music do you want on your DAP? This goes hand-in-hand with the previous factor. If you have a small 128MB DAP and want enough music to get you through your workout routine, then you need to factor that into your calculations. A player that size will get about 2 hours of 128kbps music on it. But if you go to 256kbps, then you’re down to an hour’s worth of music. Here’s a formula for figuring bitrate for a given size and how much audio you want to carry with you.

Take the size of your player in MB (Megabytes). So, an 80GB iPod is 80,000MB. Let’s use a small 128MB player for our calculations.

Multiply that number by 1,000,000 to get bytes. Manufacturers use the base-10 number for their calculations. So our player is 128,000,000 bytes, give or take (I’m ignoring certain small factors, like drive space taken up for settings and such).

Multiply that number by 8 to get bits (there are 8 bits in a byte) and divide by 1,024 (the base-2 “kilo”) to get kilobits. So our player has around 1,000,000 kilobits to play with.

Divide that number by the number of seconds you wish to get on your player. Say we wish to have 3 hours of audio, which is (3x60x60) 10,800 seconds. The answer is about 92, so you should rip at close to that (96kbps, for the base-2-oriented number) to get close you your desired amount.

There are, of course, other alternatives. If you aren’t satisfied with the above, then you can put less music on your DAP, or you could bite the bullet and buy a larger DAP.

Finally, the last factor is ego. There are MANY in the webosphere that will criticize ANY bitrate below what they feel is good. Mostly, this is ego, plain and simple. Anyone that tells me that they can hear the difference between 256kbps and 512kbps on a Metallica song playing in a Jeep with the windows down over a cheap stereo with an FM transmitter getting the audio from the DAP to the stereo is simply lying. But they want to SEEM like they’re rockstars that can make the distinction. And if you wish to avoid the wrath of their ego (which is an idicator of YOUR ego), then you may wish to go higher with your bitrate when ripping. Of course, you could always rip at what you want and just tell those nerds that you ripped at a higher rate. That should shut them up, especially when they say they can tell you ripped it at a higher rate and then you drop the bomb that they’ve been the victim of a Folgers Switch. “Interesting,” you can say, “you’ve been listening to 96kbps all the time.” Watch their face turn red.

Okay, so what’s the final answer? Well, that’s difficult to say because there are the many factor listed above to consider. I try to keep my audio in the 128kbps AAC range, although I do have some 128kbps MP3s. I can’t fix that because much of that was downloaded and I don’t have the original CDs to re-rip them (take note, you lose quality when you transcode — or change the bitrate — and you can’t increase the quality by transcoding to a higher bitrate… you’ll have to go back to the original CD and re-rip). I listen to classic rock and alternative rock mostly (with some heavy metal thrown in), so the 128kbps is fine for my not-so-discerning ear (with permanent tinnitis from too many Rush concerts). I do most of my listening in the car, so I surely don’t need a very high bitrate in a road-noisy environment. I would suggest you take my baseline and go up or down (most likely up) from there to get to your sweet spot.

Good luck, and have fun.