MAKE MUSIC NOT WAR

Forum: General Discussion

Topic: how bout a kill-motor button? - Page: 2

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Home userMember since 2003

To reply on the post of Dadegian (on page one, before this debacle started): he sais you need to pitch -100% to stop the sound. Of course that's true, but it'll really sound bad. On a real turntable this works: here, you have a continuous stream of analog audio data. On a CD or in a MP3 file, like Atomix uses, this is different. As you maybe know, this is "digital" sound, and the sound is stored as samples. These samples are little amounts of data. When you record (rip) an mp3 file, you take multiple samples of the original, about 44000 samples a second, and when you play your file now, these samples are put together, with a little time between them. This pause is so little, you even can't here it. If you pitch your sound (datastream) down untill -100%, this pause between 2 samples becomes 100 times the pause between 2 samples without pitchdown (you only get 440 samples a second), and it is possible you can hear this (well, not the pause, but you can here there's something wrong). This can be solved by interpollation. With some algorithms, your computer can calculate what he should put between 2 samples, like this he can calculate 44000 samples per second again, but to calculate this, you need loads of processing power, so your program will slow down a lot, or even don't work anymore. I don't know how they do it in VTT (I never used VTT? I'll try to test it a.s.a.p.), but I can't believe they really pitch down 100%, or they pitch down, but you get real bad music, I don't know.

Wasn't this too confusing? Sorry about my english. If I made a mistake, please correct it, I have to learn! Or if there's something not clear, please ask, I'll try to explain again.

Greetz & happy new year, ikke

Posted Sat 29 Dec 01 @ 4:01 pm

alrea

Home userMember since 2003

For a french user, your english is understandable :)
If you just use this pitch for a short time, as an effect, interpolating wouldn't take so much time processing?

Adrien

Posted Sat 29 Dec 01 @ 6:39 pm

ikke

Home userMember since 2003

OK, but if you want to pitchdown to -100% to create a kill-motor effect, it last 10 seconds or something, and that's a lot. You have to calculate 440*100=44000 extra bytes of sound data, every second. For every calculation, you use at LEAST (normally even more) processor instructions. So you get 88000 or even more instructions/second, plus the other processor time Atomix uses. That's a lot.

BTW, I'm not french, I'm from Belgium and speak dutch ;-)

Greetz & happy new year, ikke

Posted Sat 29 Dec 01 @ 6:46 pm

alrea

Home userMember since 2003

I was the french user ;)

Adrien

Posted Sat 29 Dec 01 @ 7:18 pm

wicked