Guys... Talking about MP3 quaility. It's not as suckable as you think. Get back to earth... You know what's the bitrate on ALL of your CD systems starting at 25$ and ending at 10000$? It's not more, not less, than 150kb/sec (remember those times, when we all were astonished by first 2x CD-roms (300kb/sec), then 10x, then 900x... So do the math what is 1x... And MP3 bitrate over 150kb/sec (the nearest i know is 160) is useless: too small difference, too much space. PLUS - mostly all of the decent trance tracks on the net you are (were, will be) mixing are VINYL-RIPs, which are apriori know to be of lower quality then the worst CD after 2 or three plays (even if you'll put latex oil-stopping supergloves before putting your middle finger on a 12" to cue it). Dust, moist, sometimes, heat... Listen to the best compilations mixed by the best DJs who don't even breathe on their records (once again, JUDGE JULES JUST RULES) with the use of the best Ortofons and edited by the best editors, and you'll still be able to hear "the sound of vinyl" which a cartridge's needle produces when encountering the pieces of dust on the label (which will inevitably appear even during the 5 minutes of cueing, mixing and playing). And we can all hear that when the beat goes off and some vocals (or just silence) go in. So, it all depends on where you get your MP3 from.

The last passage is on the problem of "notbeingabletodoallthetricks"... You can use keyboard binding to do all the stuff and do three things at a time (check out MJ Studio at http://www.d-lusion.com)

Peace!

Okay, I have to disagree. A CDs bitrate is 172 kiloBYTES per second.... mp3s are measured in kiloBITS... so a cd has about 8 times the amount of data as a 192kbit mp3. Single speed is 150k/sec, and since audio isn't played with data correction, the CD player can go faster at 172k/sec. Compared to 24k/sec for an mp3. But the quality difference between a well-encoded 192kbit mp3 and a CD is negligible except maybe on a really good sound system, or a surround sound system (an mp3 takes out inaudible data, a surround sound system tries to play that missing data on the rear channel, and it often sounds like crap :P)

But the fact is that alot of the mp3s that you get off the net (except the popular songs) aren't in 192; most often 128, or 160 if yer lucky. And the difference is quite apparent on a good sound system at those bitrates. I don't mind the dust sound of vinyl as much as the warbly-ness of the treble on badly encoded mp3s, or other problems like that.

And as for the keyboard binding thing, I haven't tried that program so I can't comment

But a key has only 2 states: off or on. Imagine if you could only control crossfaders and records and so forth with either on or off, not variable speed.... just think of the extra accuracy an analog system gives you to keyboard input in lets say, a racing game

I think you'll find your wrong about qualities... CDz have a frequency cut-off point of 44100hZ (the same as your average mp3/WAV) this is so they can fit huge amounts of music onto one CD. Now when you're listening to it it doesnt make much difference because frequencies below and above the ones on CD are inaudiable. Vinyl on the other hand has a cut-off point at 77000hZ which means you get much higher & lower frequency noises. These inaudiable noises make a difference to how the rest of the noises sound, so it doesnt quite sound the same... Try it, listen to a tune on a CD and listen to the same tune on vinyl and the vinyl version will sound a bit more bassy and will have higher treble ranges.

This is why if you have a good enough turntable and amp, vinyl always sounds better than CD. Ever wondered why professional DJ's never use CD? Well now you know!

So if you want proper quality mp3 vinyl ripz you make the .WAV you're ripping to 77000hZ (floating) and you get much higher quality than a CD rip (before you ask, no theres no point in doing this with CD ripz coz it wont make any difference coz the input freq is still 44100hZ)

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MUGGETS

When you encode an mp3, it cuts off any sounds over about 22000 Hz anyways, so I can't see that making a difference. Plus I don't think many programs support odd bitrates like that.

Thanks, I learned a lot of new things from your posts.

a) If you don't know what you're talking about then by all means DON'T PROCLAIM YOUR IGNORANCE TO THE WORLD !!!

b) Audio on standard music CDs is a simple 44100 Hz 16 bit 2 channel wave file. Meaning that the SAMPLING RATE is 44100 Hz (or 44100 samples per second). The best theoretical frequency cutoff is 1/2 of the sampling rate = 22050 Hz. Usually, the frequency of a CD goes up to 20000 Hz.

c) Different MP3 encoders have different cutoff values - the Xing codec and some others kill everything above 16 KHz, the rest usually cut at 20 KHz.

d) The human ear is not capable of registering sounds over 20 KHz, most people can't register frequencies above 18 KHz and quite a bit can not hear frequencies over 16 KHz !!!

e) C't (a respectable German magazine) did a subjective listening test on MP3 encoded audio and came to the conclusion that a 256 Kbit mp3 is indistinguishable from the original on CD.

f) Unlike CD, vinyl is an analogue medium, so there is no samplin frequency and hence no real cutoff value. Yet most turntable cartridges aren't capable of reproducing sound frequencies over 30 000 Hz (theses are extremely expensive audiophile carts). So even if vinyl HAD the capability of storing audio up to 77000 Hz, no cart would be able to reproduce it and it would be impossible to hear.

g) Tu-face, vinyl rips (done with conventional soundcards) can NEVER be as good as CD rips, because the audio signal goes through your sound card's Analogue / Digital converter. Since these units aren't exactly meant to encode high-quality audio, distortion and loss of sound quality is introduced. When ripping audio off a CD, it is read as digital data to begin with. Now dynamic range is a totally different thnig, and I have to say that a lot of CDs have
been recorded with very low dynamic range (on purpose). That might be the reason why vinyl sounds better compared to a CD.

h) No matter what anybody here says, no medium will be able to replace vinyl as a DJ's choice for quite some time. The ease and accuracy of spinning records and the ability to directly manipulate your medium can not be replicated by a CD player / MP3. Also, MP3 mixing programs aren't reliable enough to be used profesionally - just imagine your machine crashing in the middle of the set ... hahaha. And also, the people who go to parties want to see a DJ actually do something, not just sit in front of the computer and click around with the mouse.

peace

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djskywarp.com
:: Ways of the Wikkid :: Canada's premiere Artist, DJ, Promoter, and Club Portal ::

As a response to a) and c), I admit I pulled the 22000 figure out of my ass, but I knew the cutoff was close to that Regardless, you aren't gonna have 77000Hz sounds saved in mp3 format....

And I believe that even those people can't hear anything above 20000Hz or so, a 80KHz recording would sound better than a 40000Hz recording just because of the higher 'resolution' that you'd get of the sound...

Regardless of the sound quality of 256kbit mp3s, you barely ever get mp3s of that high quality off the net... so unless you're talking about ripping your own cds at 256kbit and spinning those, it isn't an important point.

Correct me if I'm wrong, but if you had a digital connection from the turntable to the computer (optical or whatever), would that not have better sound quality than a cd?

Hopefully someone more knowledgable than me (skywarp) can see if I'm missing anything here

You confuse sample frequency of a wav file (44100Hz) with the maximum frequency of the sound wave that can be recognized by a human's ear (It's a certain value of 16kHz, not more. It has nothing to do with anything but physics). The confusion can be compared with the following:

Frames per second on your screen during some game have nothing to do with the inability of a human's eye to "refresh" the picture more than 24 times a second. So the more - the better.

Now, about the mp3 compression. Once again, let's refer to biology: there is a threshold, after which even the best systems won't give the ear an opportunity to recognize the difference. If not consider a zooming factor, a JPEG file with a compression rate of approx 95 will give you the same quality (for your eye) as the original. Where there are less colors used, it's a little bit more (due to the technology of JPEG compression). We can transit the same thing to the MP3 files.

Now, in packed clubs you will never get sound as nearly good as on the average sound system (crowd lets everyone know how big it is. So there will be no noticeable difference between the superclear CD and a 160 kbps MP3. And if you go to clubs to listen to the music and not to dance, then you've got a really big problem.

...

A DJ on turntables does not more things than a DJ behind the computer, if looking from aside.

Jocker, there is a direct relation between the sample rate of a piece of music (digital, uncompressed) and its maximum frequency range - which, theoretically is exactly

sample rate / 2 = maximum frequency

I wouldn't be able to tell you why off top of my head, but it is so. Hence, let's say an Audio DVD would have 96KHz sampling, and the maximum theoretical frequency would be 48KHz. What Morbius said, though, about higher sample rate having higher resolution is true ... high sample rate recordings sound better because of that fact, not because they can reproduce higher frequencies.

Ok, technical babble aside, the reason that MP3 won't replace vinyl at clubs / raves isn't sound quality - it is easy to encode a MP3 to sound just as good as vinyl, and like Jokcker pointed out, very few clubs have systems of such quality where one could notice the difference between MP3 and CD or vinyl. The thing is, it is just more convenient to spin vinyl than CDs or MP3 ... I don't know if you're a DJ yourself but if I had a choice what medium to use at a party, I would use vinyl without even having to think twice. Like I already said, it is just more intuitive to be able to physically manipulate the record than having to twiddle with pitchbend buttons and other workarounds used on professional (DJ) CD players (don't even get me started on MP3 DJ programs ... ).

Morbius, whenever you have an analogue source being converted to digital, the signal has to go through an Analogue/Digital converter. The quality of that converter is crucial to the quality of the recording. Your soundblaster class cards usually have a very poor A/D converter, which is also under a great deal of interference from other components in the computer. That is why professional sound cards that are designed to do stuff like that cost $500+. And I don't know of any turntable that has digital out, besides the new Denon series. But again the signal has to be converted to digital at some point. Yet most of the time the quality of the record itself and the cartridge used to play it is the limiting factor (the DJ cartridges sound very bad, in audiophile terms ...).

yeah, just spilling my thoughts here ... hope you can use this, and feel free to correct me if I'm wrong.

peace

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djskywarp.com
:: Ways of the Wikkid :: Canada's premiere Artist, DJ, Promoter, and Club Portal ::

I am a DJ and I absolutely agree on the fact that vinyl is the most user-friendly medium. I just tried to point out for those who say that MP3 mixing sucks that it's not as suckable as it seems... Of course, nobody is going to play in the clubs, using the computer. But if you are at home, MP3 mixing really gets to the front because it doesn't cost you spit to download, listen to and learn the very new tracks from the net, while you have to spend about 100$ to get a 1-hour set on vinyls, half of which you probably won't like.

Just thought I'd help clear this up.

CD quality audio is 44.1 kHz, 16-Bit stereo digital audio.

As skywarp said, Nyquist theory says that the highest frequency that can be represented without aliasing in a digital system is just under half the sampling rate. Also, the dynamic range of a digital system is approximately 6.02 * no of bits.

So CD has a frequency cutoff of about 22kHz and a dynamic range of about 96dB.

The bitrate of CD-Audio is therefore 44.1*16*2 kBit/s. As also mentioned above, CD-Audio includes error detection and correction using a method called Cyclic Redundancy Check. The data on the disc is actually encoded as 96 bit words which includes CRC and 8 layers of sub-code (for describing time and index and track info) as well as the audio.

mp3 works using psychoacoustic principles similar to the ATRAC system in minidisc. As mentioned, the first thing to go is high frequency response for 2 reasons - you need a higher bit rate to encode it and you can be quite harsh before you notice a big difference.

Secondly, masking theory says that a loud sound will mask a quiet sound if they're of similar frequency, so mp3 gets rid of anything which would be masked - you can hear it if you listen to something that's sustained with a regular percussion over it, the strings (or whatever) appear to get quieter when the percussion sounds.

Thirdly it squashes the dynamic range.

When an mp3 says 44.1kHz 16-bit, it means that is what the source was, not what you're listening to.

About higher sample-rate == higher resolution. It only affects frequency response, and what you're hearing as higher resolution is actually the parts of the sound above the normal cutoff. Hence, if you recorded a 100 Hz sine wave at 500Hz, 44.1kHz or even 10,000 GHz, and then played it back, you'd notice no difference.

Theoretically, vinyl is the ultimate recording system because it has an infinitely high sampling rate. Unfortunately, it's dynamic range is only about 60dB because of the noise floor.

Any questions?

Everything's clarified