CD bitrate?

I’m a little confused about the bitrate on audio cds, is it 1411 like wav files or 1536 like PCM on dvds. Thanks. :confused:

Bitrate 1411?? lol

A bitrate for plain CDDA Audio, for what purpose?

It’s 44100 Hz or 44.1 KHz.

Audio CD’s native format is 44.1 kHz, stereo.

Yeah thanks I figured it out 16 bit * 44.1 kHz * 2 channels = 1411

I just wanted to make sure I wasn’t losing quality when I was ripping my cds to wav files.

Er… maybe next time you should be a bit more careful before LOLling… :bigsmile:

Regards, :wink:

ET

EDIT: opps… bob23, you were faster than me! :stuck_out_tongue:


Thanks eltranquil

I thought bitrate would mean bits per second. Is this not correct? If it is bits per second then it would be 1,411,200.

I meant 1411 kpbs, you are right.
1,411,200 bps = 1411.2 kbps ~ 1411 kbps

Yes. Even “dimensionally”, multiplying bit * kHz you get Kbit/s. :slight_smile:

ET

oops. I understand, sorry bout that.

Don’t forget the number of channels. :slight_smile:

44100Hz × 2 channels (stereo) × 16 bits per channel = 1,411,200 bits per second.

Isn’t it what bob23 said a few posts above?

However, I think that it is quite clear now. :bigsmile:

Regards, :slight_smile:

ET

OK, I was under the impression that a bitrate for an standard AUDIO-CD isn’t that important at all, because it’s always the same anyway. :wink:

However, it seems to be solved, thanks to you guys.

Yup and it seems that you missed it (or just had a lapse… ?) because when you repeated it you left the number of channels out of the formula.

No :disagree: , I just spotted the dimensions that were present in the formula (like you do in physics): bits (16), kHz (44.1). I don’t see the 16 as bits/channel but merely bits: for me the ‘2’ of the two channels was a pure number (with no dimensions, like sin x), so I didn’t mentioned it.

ET

Well, fellows i think that "1411200 b/sec is not quite correct number…

We talking about AUDIO CD bit rate. The PCM audio tracks have constant bitrate. That bitrate actualy defines the size of the cd medium converted from lenght in min (74 or 80) to bytes capacity.As you know cd audio players reads cd tracks on 1x speed. First speed is very close somewhere near 150 Kbytes/sec.Thats not just my words, but as i know a international auido standarts! What i really mean? Let`s see:

1x=~(150 kbytes/s)*1024= (153600 bytes/sec)*60=(9216000 bytes/min)*80 min=((737280000)/(1024))/1024= 703,125 Mbytes total cd space, like we expected ,right?

I`m not so sure about yours calculations:

“”“16 bit * 44.1 kHz * 2 channels = 1411200 bits/sec”"", because,
(1411200 bits/sec)/8= (176400 bytes/sec)*60sec=(10584000 bytes/min)*80min=((846720000 bytes)/1024)/1024=807,49 Mbytes total cd space. WOW!

Quite big contradiction,dont you think!??!?!??!!?! :))))))))))) I made a experiment with 30 audio (WMA) files with total lenght of 4772 sec.They perfectly fit on 703 mb cd as AUDIO PCM format.Lets do math again: 4772 sec*153600 kbyte/s=732979200 bytes= 699 mb + 1 mb file system =700 mb finaly burned to audio CD.
If your theory (1411200 bits/s) is right , it will newer happen.You do the math by yourself with your constant like me (^).

Therefore, bitrate of PCM AUDIO CD TRACK is 703mb/80min=149,9~150 kbytes/sec or FINALY (150*1024)*8=1228800 BITS/SEC.

From www.wikipedia.com

"The bit rate is 1411.2 kbps:

44,100 samples per second × 16 bits per sample × 2 channels = 1,411,200 bps = 1,411.2 kbit/s.

As each sample is a signed 16-bit two’s complement integer, sample values range from -32768 to +32767.

On the disc, the data is stored in sectors of 2352 bytes each, read at 75 sectors per second. Onto this the overhead of EFM, CIRC, L2 ECC, and so on, is added, but these are not typically exposed to the application reading the disc.

By comparison, the bit rate of a “1x” data CD is defined as 2048 bytes per sector × 75 sectors per second = 150 KiB/s, or approximately 9.2 million bytes per minute."

These calculations are done in base 10 whereas byte_math did all the calculations base 2.

FWIW 1536 for DVD PCM is because of the 48 KHz sample rate.