Axiom Home Page Forums General Discussion Home Theater MP3 vs Lossless Compression - the proof

Doh! I can't believe I made that mistake. Thanks for clearing that up. So that means that the MP3 would be using 1/8th of 1/6th (in round terms) of the bandwith of an average slow wireless network connection. That's something like only 2%.

Well let's assume that an 11 Mbps wireless network gets 6.4 Mbps real-world transfer rate. This would be 6400 Kbps (not [6.4 * 1024] since network transfer rates are base 10 and not base 2), which equates to twenty times the bandwidth required by a 320 Kbps MP3. In this scenario, the MP3 would take 1/20, or 5 % of the wireless bandwidth. In the real world, unless you have a very good transmitter and card (or a signal amplifier somewhere in the chain), you are not going to achieve this speed at a long distance. If I walk around my apartment complex into friends' places, even with my 802.11 G network I often dip down to about 1 Mbps which is 1000 Kbps. This would mean that if I am playing a 320 Kbps MP3, I would be using roughly 1/3 of the network bandwidth.

(Note: I am not taking into consideration any error correction and which would lower the transfer speed further when the signal is poor.)

Also keep in mind, that at this speed (1000 Kbps), we are under the 1411 Kbps requirement for Redbook Audio CD Playback. Here is a situation in which compression proves useful.

The math:

Uncompressed redbook audio:
44100 (samples) x 16 (bits - 2 bytes) x 2 (channels) = 1411200 bps or / 1024 = 1378 Kbps

Bren R.

BrenR's correct... Just that since it's in bits instead of bytes, it is not 1378, but rather 1411.2 Kbps (since throughput is base 10 number system not base 2).

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Just that since it's in bits instead of bytes, it is not 1378, but rather 1411.2 Kbps (since throughput is base 10 number system not base 2).

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Oops... yes, it's kilo as in the metric prefix for thousands. I originally had it in KB/s, of which there are 1024 bytes to a KB (and 1024 KB to a MB, 1024 MB to a GB - regardless of what the snot-nose at Future Shop tells you), realized my answer was in a different unit and forgot to change the equation.

Bren R.

Yep yep - I'm still surprised at how many people think that a KB is 1000 Bytes... Scary how they end up working for computer shops, heh.

The really sad thing is the whole disk size "scandal." Well, I call it a scandal. I don't understand why disk sizes are measured base 10, so that a "120 GB" drive is really only ~111.76 GB. Then formatting and partitioning it gives us even LESS usable space; simply unfair!

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I don't understand why disk sizes are measured base 10, so that a "120 GB" drive is really only ~111.76 GB.

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I think the first time I ran into that was with my gigantic Samsung I think it was... 560MB or so... was actually 546 or so, then after an FDISK and FORMAT... less again.

I felt ripped off.

Bren R.

Such a scam! Here's another computer scam that upsets me: CAV (constant angular velocity) drives only giving max speed, instead of both the minimum and maximum. If everything were just CLV (constant linear velocity), there would be no problems with this, but every drive maker wants to have the highest speed rating - *shrug*.

Very interesting, Bren and Will, but true audiophiles want to know which sounds better, a bit or a byte?

A byte - it would contain 8x the information.

Ha - bet you didn't expect a clear answer.

Bren R.