Looping Samples with Math’s.

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Sharp
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Looping Samples with Math’s.

Post by Sharp »

Hi all.

Here’s a tip for looping drums using Math’s.

Tip 1 – Drum Loops

Hz x Beats x 60 / by BPM = Your loop point in Samples.

“Hz” is the frequency of your Sample.
“Beats” is the number of beats in your Drum Loop.
“60” is a constant value that comes from 60 seconds in B – “PM”
And the BPM is the speed of your drum pattern.

So now that you know that, lets say you have a 4 beat, 60 BPM / 48Khz drum pattern and you would like to loop it perfectly in time so that it does not wander above or below 60 BPM even if held for long time.

Here’s what the sum for that would look like….
48000X4X60/60= 192000

So your start loop point is 0 and your end loop point is 192000
That’s all there is to this.

I’ll post another tip that works out the loop points for instruments later. It’s far more complicated but it’s well worth the read.

Regards.
Sharp
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Stephen
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Post by Stephen »

Thanks Sharp!
:D
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Diego
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Post by Diego »

Can you give a demonstration of why it works?
I can't beleive a simple calculation can work!

reagards!
Diego http://www.myspace.com/diegoinmusic

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Sharp
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Post by Sharp »

Hi didoxxy.

No problem, if you look at the sum above you will see that I said the BPM of the loop was 60BPM. I did that for a reason. I was hoping that anyone reading the post would noticed that the answer “192000” divided by the number of beats = 48000 which is the same number of samples that can be found in a 48Khz sample 1 second long. And the sample is 48Khz.

Same rule applies to everything else. If you change the frequency, then that value corresponds to everything else. For example, a one second long 44.1Khz sample will have 44100 samples in it.

Because we know that, the math’s above works in any situation.
The example was an easy one; you actually get the most benefit out of this sum when you start throwing other BPM at it.

For example, a loop 4 beats long at 132Bpm and at a quality of 48Khz works out at…..

Start Loop point 0.
End Loop point 87272

Pretty cool huh !!!!.
This will give you such a perfect loop that it will never fall out of time with your song.

Sampling is an Art :-) You won’t find this stuff in the manual.

If you think this sum is good, wait until you see how you can find out the loop point of an instrument using nothing but maths. That one will blow your mind. It’s far more complicated so just give me a moment to word it correctly so it’s clear enough to follow.

Regards.
Sharp.
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Diego
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Post by Diego »

Hi Sharp!

thanks a lot for your explaination.
very clear!

Regards
Diego http://www.myspace.com/diegoinmusic

Korg M3 with EXB Radias & EXB-256 onboard
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Sharp
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Post by Sharp »

No problem.
I’m glad you asked. Pretty cool trick huh !!!.

Regards.
Sharp.
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Diego
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Post by Diego »

Yeah, really cool trick!

Thanks again for sharing it!
Usually I don't sample anything, but I must admit that it's a good trick to have in my pocket!

regards
Diego http://www.myspace.com/diegoinmusic

Korg M3 with EXB Radias & EXB-256 onboard
MOTU Traveler - iBook G4
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aman_sam123
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loop point of an instrument using nothing but maths.

Post by aman_sam123 »

please tell how to calculate loop point i m very interested to know it, i like what you have written in teh material here.
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