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Q ... Quite often just before the release into the body of the song, you'll hear what sounds like a percussive hit (or sweep or swell) with a super long decay that just ends up sounding like white noise during the body of the song and this noise will continue till the end of a section where it is usually faded.
The question is, how do you tweak a sample so it will carry this characteristic without sounding as if its being looped?
Any help much appreciated...
A ...First of all, you could just loop a sound and filter it, that's a valid technique that I've used a number of times in cases where I need more control over the length and filtering of the resulting repeats.
But it sounds to me as if you're describing a tape delay with high feedback and filtering.
Luckily these days we don't have to fork out a small fortune for a second hand Roland Space Echo to get the same effect. We have some very generous and talented programmers that have created some excellent emulations that are made available for free such as the one above; Retro Delay by Image Line.
For another excellent tape delay emulation plug-in with a particularly nice sounding tape distortion in the feedback path, try the free Bionic Delay created by Daniel Interruptor:
Set the feedback parameter to around 55 and dub out, but be ready with the channel fader to control your volume.
You can download it from Daniel's site here here
Another excellent option is E-Phonic's suitably retro looking "Retro Delay" which also has an optional spring sounding reverb in the delay path (similar to the Roland Space Echo) along with various other tape saturation and distortion emulations for authentic gritty Jamaican dub studio aesthetic:
Link to E-Phonic's site where you can download Retro Delay here
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