Author Topic: MP3 questions. (Read 758 times)

miko2d · « **on:** January 06, 2004, 10:35:05 AM »

Gents,
I am new to MP3 and I am considering a purchase of an PM3 player. I know the basic theory but not the details.

I need it to hold speech rather than music - two types of it:
1. The books that just have to be of decent quality.
2. Language lessons that have to be a good quality though probably not as good as music.

I understand that the standard encoding for music is 128 kbit/44khz stereo.

What would be good encoding parameters for speech?

How do I calculate capacity required? While we are at that, what's the duration of a standard "song" used to advertise the MP3 players capacity.

I am thinking whether I should 1.5 GB or 20GB model, the former being much more compact.

I intend to store a few hundreds of hours of speech.

What MP-3 player wold you recommend?
It is important that it has a good file management system that will allow me to group items into categories.
Are there MP-3 players that allow quick rewind by a few seconds - which may be important in a language course.

What good and preferably free software I could use to encode (rip) the CD content and re-code the existing MP3s into smaller files?

What about tracks? How many tracks can I split a piece into? How do I do that? Do I need to? Can I fast-forward to a place in text without using tracks?

What else should I know?

Thanks,
miko

Chairboy · « **Reply #1 on:** January 06, 2004, 10:46:45 AM »

I can answer one thing, I've found that 32k encoding is perfectly adequete for spoken word.

vorticon · « **Reply #2 on:** January 06, 2004, 10:55:50 AM »

Quote

How do I calculate capacity required? While we are at that, what's the duration of a standard "song" used to advertise the MP3 players capacity.

capacity required = size of song in megabytes...the actual length has nothing to do with it...

Quote

I am thinking whether I should 1.5 GB or 20GB model, the latter being much more compact.

20GB...more compact and you say you need "hundreds of hours"

capt. apathy · « **Reply #3 on:** January 06, 2004, 12:50:10 PM »

128 kbit/44khz is CD quality sound. I rip my music at 160 (I like a little over-kill). at 160kbit/44khz an average song is about 4MB

kappa · « **Reply #4 on:** January 06, 2004, 02:10:32 PM »

Quote

Originally posted by Chairboy
I can answer one thing, I've found that 32k encoding is perfectly adequete for spoken word.

This, I would think, would be correct..

Miko,

How do you plan to record your voice? Why are you needing an mp3 player?? Are you planning on replaying your voice for an audience? There are many storage devices availible right now. If you plan just to dictate at home, perhaps you might store the files on your home computer. They have small devices now that will fit on your keychain and plug directly into a USB port that act like an external HD. My friend got one that is a little larger than a cig. lighter that holds 128megs. Thats roughly 2 hours of music. Maybe 8 hrs of voice recorded at 32k... Maybe more... If the mp3 player is merely just to move data around, you might want to check into the above mentioned..

Also, if your using a personal recorder, it probably wont record in mp3 format. Conversion from wave to mp3 is pretty simple and many types of progs can be DL'd that will convert wave to mp3 and vise-versa. I use a very old prog. called DB Poweramp I think.. very simple... I could send it to you... I dont like winamp... it has too much 'stuff'....

Trying to think if I have seen a personal mp3 that has a voice record option and I'm drawing a blank.. Further explanation of the intended use might help. But bottom line, if your planning on archiving that much dictation, you should consider either an external or internal HD ... Perhaps even backup w/ some sort of RAID configuration...

miko2d · « **Reply #5 on:** January 06, 2004, 02:19:53 PM »

kappa: Miko,
How do you plan to record your voice? Why are you needing an mp3 player??

Not my voice. I have a lot of educational CDs - language and other subjects - and an access to many hours of educational lectures in MP3 that I can download off the web for free.
We are talking about an hundreds of hours here.

I want to always have it with me so I can use time that is otherwise wasted - driving, waiting, rocking a baby to sleep, etc.

I do not care much about playing it aloud.
If it had a voice recorder, that would be nice but not essential.

miko

Tarmac · « **Reply #6 on:** January 06, 2004, 02:22:01 PM »

If you're intending to rip a few hundred hours of speech, that sounds like a few hundred CD's. A small flash memory player probably won't cut it then. A hard disk player sounds like the way to go. There are new mini-HD players that supposedly hold around 2GB, but I have no experience with them.

From what I've seen, the HDD based players (Apple IPOD, Creative Nomad, etc) allow better organization of songs since they have full LCD screens instead of the small info displays on the flash-based players.

As far as software, I use Poikosoft's Easy CD-DA 5.0 to rip. It's free at download.com for a trial version. The quality can be set as low as 8kbit/s; I don't know if you can turn down the frequency from 44khz. I'd just play around with it, and look for the happy medium between file size abd quality.

I'd search download.com for "CD ripper" or "audio encoder" or "audio converter" programs. There are lots of free demo versions of the software that will allow you to see all the features of a particular program.

Once you've got a general idea of the number and sizes of the files you'll be playing, it should become clearer as to how much capacity you need.

kappa · « **Reply #7 on:** January 06, 2004, 02:23:28 PM »

Quote

What good and preferably free software I could use to encode (rip) the CD content and re-code the existing MP3s into smaller files?

mp3, as far as I know, will be the smallest files size you can reach that will be playable on a wide spectrum of devices. Another file type that may be smaller than mp3 is .raw.. These type files are not as usable as say a wave file or mp3.. Mp3s compress to roughly 10% the size of the Wave file... A 60 meg wave file song will compress to about 6mb mp3... I have a very good prog for this..

Quote

What about tracks? How many tracks can I split a piece into? How do I do that? Do I need to? Can I fast-forward to a place in text without using tracks?

You could prolly goto download.com and get a prog for this. Probably most any basic audio editor will give the ability to do this. Length of track probably has a lower end, but a track a few seconds long would not by unimaginable... Upperend would probably only be limited to memory.. Fast-forward options would almost certainly by limited to your playback device...

Hope this helps.. 8)

kappa · « **Reply #8 on:** January 06, 2004, 02:32:34 PM »

Quote

Originally posted by miko2d
Not my voice. I have a lot of educational CDs - language and other subjects - and an access to many hours of educational lectures in MP3 that I can download off the web for free.
We are talking about an hundreds of hours here.

I want to always have it with me so I can use time that is otherwise wasted - driving, waiting, rocking a baby to sleep, etc.

I do not care much about playing it aloud.
If it had a voice recorder, that would be nice but not essential.

miko

Tarmac prolly has the best option unless you plan to carry all hundreds of hours of content with you everywhere you go.. Mp3 players are nice and now you can even by car stereos that have a direct input where you can plug an mp3 player directly into your car's radio.. Also, some Mp3 players now have removable memory where as you can carry a few memory disk w/ one player...

As far as lecture in wave format on Cds... Thats no worry.. Just need a ripper with conversion prog for Wave to Mp3.. DB Poweramp has been good for me.. Dunno if its still around though.. It was so good and simple that I've had it for years... Mp3s reduce down to roughly 10% of the wave file size..

Pfunk · « **Reply #9 on:** January 06, 2004, 03:46:04 PM »

Just buy a Creative Labs Zen Nomad, it holds 30GB of data is no bigger than your average wallet and cost much much less than an IPOD.

Look around you can find deals on them...for example here is the 40 GB model for $319

http://www.amazon.com/exec/obidos/tg/detail/-/B0000DFZ67/qid=1073425506/sr=1-1/ref=sr_1_1_etk-electronics/002-9997780-6952813?v=glance&s=electronics&n=172282

Buy.com for $294.99

http://www.buy.com/retail/product.asp?sku=90127419&dcaid=1688

Pfunk · « **Reply #10 on:** January 06, 2004, 03:51:26 PM »

software that allows far more options than the one that is bundled with the nomad

http://www.redchairsoftware.com/notmad/

DA98 · « **Reply #11 on:** January 06, 2004, 04:08:40 PM »

One of the best audio format converters is CDex (and since it's free, we could say that it's simply THE BEST format converter

). It can be downloaded here.

One minute of audio encoded at 128 KBPS/Stereo equals roughly to 1 MB. If you use 32KBPS/Mono you have 8 minutes of audio in one MB. With a 20 GB unit you have... +/- 2.600 hours of audio, or 108 days of continous speech. I suppose it's enough... you could also encode the files with Variable Bit Rate, wich reduces the size of the file without compromising quality (or the inverse); it should be very effective with speech.

JB73 · « **Reply #12 on:** January 06, 2004, 05:46:59 PM »

i bought this:
http://www.nomadworld.com/products/Jukebox_ZenXtra
for myself from Christmas money (the 30GB version)

i LOVE it!

with usb 2.0 i can transfer 1000 songs in 20 min.

sound is great.

battery life is odd... i did what the manual said and charged for 4 hours or more before using it... but sometimes it lasts like 2 days other times for 1/2 day. i guess it has to do with how much you really play it.

charge takes about 2 1/2 hours.

menu is decent.. though there are options i wish it had.

storage size is good too. i have over 1100 mp3's (average size 128bit rate is about 3.5MB), both the current AH and AHII beta 1.99.7 full apps and about another 1/2GB of misc carp on it. i still have over 23GB available on it.

best buy had a rebate offer and i got it for $249 US. pretty good deal IMHO.

i dunno where you live but it is illegal to drive and listen to headphones in WI... you'd need one of those CD player adapters for a tape deck or something.

Staga · « **Reply #13 on:** January 06, 2004, 06:26:16 PM »

Does any of those players support Ogg Vorbis ?
At lower bit-rates Ogg is superior to Mp3 and IMHO at higher bitrates it also sounds better than mp3 does.

capt. apathy · « **Reply #14 on:** January 06, 2004, 06:35:03 PM »

Quote

i dunno where you live but it is illegal to drive and listen to headphones in WI... you'd need one of those CD player adapters for a tape deck or something.

the tape deck adapter sucks. if you go that route get the 'audio-bug'. it plugs into the headphone jack and then broadcasts to FM, just turn your car stereo to one of 4 channles. about $30-35