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General Forums => The O' Club => Topic started by: miko2d on January 06, 2004, 10:35:05 AM

Title: MP3 questions.
Post by: 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
Title: MP3 questions.
Post by: Chairboy 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.
Title: MP3 questions.
Post by: vorticon 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"
Title: MP3 questions.
Post by: capt. apathy 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
Title: MP3 questions.
Post by: kappa 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...
Title: MP3 questions.
Post by: miko2d 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
Title: MP3 questions.
Post by: Tarmac 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.
Title: MP3 questions.
Post by: kappa 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)
Title: MP3 questions.
Post by: kappa 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..
Title: MP3 questions.
Post by: Pfunk 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
Title: MP3 questions.
Post by: Pfunk 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/
Title: MP3 questions.
Post by: DA98 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 (http://www.cdex.n3.net/).

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.
Title: MP3 questions.
Post by: JB73 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.
Title: MP3 questions.
Post by: Staga 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.
Title: MP3 questions.
Post by: capt. apathy 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
Title: MP3 questions.
Post by: JB73 on January 06, 2004, 06:37:26 PM
Quote
Originally posted by capt. apathy
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
ya.. i been looking into one of those myself. you got a link?
Title: MP3 questions.
Post by: capt. apathy on January 06, 2004, 10:23:28 PM
http://www1.dealtime.com/xPO-Mito_Mito_AUDIO_BUG_Wireless

since my cd/mp3 stereo was stolen from my car last summer, I've decided to go with a cheap stereo in the jeep, and use the audio bug with either an mp3 discman or regular mp3 player. (hopefully soon, this no-music thing is killing me)

if the range is good enough this would also allow me to buy cheaper, more disposable boom-boxes for work, and just keep the mp3 player in the tool bucket where it won't get burned up.
Title: MP3 questions.
Post by: miko2d on January 15, 2004, 08:22:14 PM
I've got myself a Nomad Jukebox Zen NX.

 So far the only good thing I can say abut it is that it took me one minute to get a support guy on the phone - not that he was able to help me but he was very nice.

 My home computer (Win 2000) installed fine. The sofwtare interface is crappy but I figured out which button does what.

 I've got a bunch of lectures encoded at various bit-rates - from 16kbs and up. Loaded them into the Nomad and tried playing them. Some play fine, others are slowed down - with corresponding low pitch.
 All of them sound great in every single software player I have on my computer - 5 or 6, even the Creative Media Source itself.

 On my office computer the software installation seemed to go through fine, but the software does not see the nomad when it is plugged in. The operating System (Windows 2000) sees that it is plugged in and recognises it by name but the device manager claims the drivers are not installed. I've wiped it out and reinstalled several times, same result.

 miko
Title: MP3 questions.
Post by: JB73 on January 15, 2004, 08:31:56 PM
bummer dude im sry to hear that.

mine has worked great since day one.

yes i'm using win98 @ home but my buddy's PC is XP and i loaded all the software there too. all works fine.

did you try DL'ing new drivers from creative for the win2k maching @ work?

do you have permissions to add new hardware @ the work PC?

how about on the taskbar... is there an icon for the new device and is there an option to "connect" it (again @ work)?


for the audio tracks... when they are playing slowed down did you check if the EAX settings were on and what they were set to? (there is an option to slow down or speed up audio)

let me know
Title: MP3 questions.
Post by: AKS\/\/ulfe on January 15, 2004, 08:34:00 PM
Quote
Originally posted by capt. apathy
128 kbit/44khz  is CD quality sound.  


172KB/s  16 Bit  44,100Hz is CD quality.

128 is a noticeable downgrade from CD quality music.
-SW
Title: MP3 questions.
Post by: miko2d on January 15, 2004, 09:06:14 PM
JB73: bummer dude im sry to hear that....

 I can install stuff on my office PC - which is pretty much my only way to get phone tech-support, since by the time I get home and sort out the babies, the working hours are usually over.

 There is a standard icon of an external device that appears on a taskbar when I plug it in, and it offers an option to disconnect it. It knows the device by name but it is marked as "missing a driver".

 The EAX were off originally. I tried the EAX on and off and various time rates. Since it accelerates the play without changing the pitch, there is no way to make it sound like it is supposed to - only to shorten or prolong the torure...

 I will try to DL the drivers tomorrow on my office PC. I see that they have a driver update from 26 Nov 2003 that supposedely Resolves the issue of the "Device not connected" and a firmware update from 24 Nov 2003.
 
 If it does not work, I will probably return it.

 miko
Title: MP3 questions.
Post by: Pfunk on January 15, 2004, 09:46:52 PM
see my aformentioned post...the software that comes with the Nomad is chit.....try this instead


http://www.redchairsoftware.com/notmad/
Title: MP3 questions.
Post by: sshh on January 16, 2004, 12:53:34 AM
Miko try figure out what is common thing in those mp3s that dont play well. It could be lower encoding bitrate (16 vs 32 vs 64 kbps), different sampling frequency (44 vs 41 vs...), encoded using VBR  (variable bitrate) or CBR (constant). Other than that drivers and player OS (firmware) update may help too. But I'd rather try figure out whats wrong with specific files first. Only then update player OS.
Title: MP3 questions.
Post by: miko2d on January 16, 2004, 11:30:39 AM
The driver update cleared the problem of the invisible Nomad.
 The firmware upgrade did not help much.

 I made a test of a dozen of various kinds of encodings using CDEX. CDEX allows to use the LAME encoder or window MP3 codec.

 The lowest bitrate that works seems to be using the windows codec 24kbs/22,050Hz.

 The LAME encoder set at that rate or at 16000Hz works too but the actual rate it produces is much higher - apperently one can specify the minimum rate but not the fixed one.

 The Nomad just seens having trouble playing anything at 11,025Hz sample rate and while it plays 18kbs/16000Hz files fine, I have no way to encode at those settings.

 24kbs/22,050Hz is still 5.3 times more compact than 128kbs rate - which makes moving and storing the files easier, so I will probably keep the Nomad.

 Thanks for your advice.
 miko
Title: MP3 questions.
Post by: sshh on January 16, 2004, 09:58:27 PM
Glad to hear is works. I'm not sure what you mean by :

Quote
The LAME encoder set at that rate or at 16000Hz works too but the actual rate it produces is much higher - apperently one can specify the minimum rate but not the fixed one.


Is that 16 kbps ? Anyway Lame of course has options to specify lower bitrate (as low as 8 kbps) -b 8 or -B 8 for maximum allowed rate - see here http://lame.sourceforge.net/USAGE

Also there is option to set sampling freq and Lame supposed to resample original file to your wishes --resample 8 for  8 kHz. You may try RazorLame http://www.dors.de/razorlame/ to play with Lame options without actually typing them in the command line and looking up the manual.

Last link for today :D  http://www.exactaudiocopy.de/ - best CD extraction tool. And quickstart doc for it http://www.ping.be/satcp/cd2mp3-en.htm
Title: MP3 questions.
Post by: miko2d on January 17, 2004, 01:31:17 PM
CDEX uses LAME encoder as a promary MP3 encoder but can also use window codec which happens to be Frounhoffer algorithm.
 So I am not using LAME directly but via CDEX. I suspect that LAME allows to set the exact bit rate but CDEX apparently only allows to set minimum bit rate when working with LAME.

 16000Hz I mentioned was a sampling rate, not a bitrate. Sampling rathe is how many samples per second are taken from the signal. It should be a bit over twice the desired frequency range, so for reproducing music in the whole range a human ear can hear it (100-20,000Hz) the sampling rate of 44100 is standard.
 Other common sampling rates are 22050 and 11025 but any other one is possible.
 For speech, 4KHz is sufficient, so a rate of 8kHz or 16kHz is fine.

 The higher the sampling rate, the better high-frequency fidelity.

 With the set bit rate, the higher the sampling rate, the fewer bits are available for encoding each sample.  The fewer bits ised to encode each sample, the greater the sampling error, which is exibited as increase in noise.

 Standard .wav files use 16 bits to encode each sample - 32,000 values at 44,100 samples per second.

 So there is a tradeoff between frequency reproduction and noise.

 Thank you for the links, sshh.

 miko
Title: MP3 questions.
Post by: JB73 on January 17, 2004, 04:45:12 PM
umm you know and understand all that and are asking lowley schmucks like me about advise on mp3 players?

again hope it works out