How do I turn a discrete sound effect into a seamless loop?

Development Audio
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So, I’ve got this sliding mechanic, and I’ve got a sound effect here off of freesound, and right now the fact that it’s looping is painfully obvious.

I’ve been trying to learn Audacity and Metasounds to try and find a remedy, but all the tutorials I find online are for looping music and my attempts to transfer that to a sound effect don’t work. I’ve attempted to cut overlapping segments from the beginning and end of my sound, swap them and crossfade, but I can’t get a good result.

Any advice? A tutorial you could recommend perhaps? Or at least explain to me how you’re suppose to convert a discrete sound into a looping one because I don’t think I even understand the theory here.

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It is a short sound, which doesn’t help. Although I do think it’s possible to get a better result than you have there.

To be clear, you need to make the end of the loop sound like the beginning. So cut a chunk from the start of the loop, and put it on another channel at the end. Then crossfade between the real end of the loop, and your pasted segment. Then it has to fit.

Just upload the sound here, if you can’t get it working…

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Well, if the duration’s the issue I was able to get a decent elongation with a paulstretch. A little spooky sounding but for this game that’s a-okay. But I still can’t get a smooth loop :c

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I’ve also tried isolating the beginning and end of the slide, figuring I could do something like

Start Slide → Looping middle bit → End Slide using metasounds or blueprints or something.



But again, looping the middle bit is rough. I just can’t seem to hide the transition.

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Is one of these the original? Ah, it’s the second, right? :slight_smile:

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I’m thinking it might be easier to generate a longer version with white noise, similar sounding to the first bits of that sound part you posted, then work from there. Audacity can do it but you get more flexibility with software like Reaper (volume / pitch / sound generation graphs). You could also add in noise recorded with a microphone (crumbling paper, moving rice, grinding stone etc.). Very short sound effects are not easy to stretch I think…

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The shorter one is the original clip, the longer one is modified.

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Was there something wrong with my paulstretched solution? Is 10-11 seconds still not long enough?

I’m hesitant to try learning additional programs right now since I’m already a bit overwhelmed with learning every other aspect of game dev. I might try out Reaper like, a year from now when I’ve got a better grasp on my current tools.

And my current setup is not conducive to audio recording :c

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Personally I dislike stretch because it is a very noticable effect on its own. The original sound’s characteristics and details are lost.

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I had a try, but the whole sound it too short. You need a longer sound to start with, sorry :slight_smile:

Even with a crossfade, you will get a pulsing sound.

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How long does the sample need to be?

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I’d like to take the old games as example, where sound quality was simple and files small.
Old Tomb Raider 1 had this sliding sound played right here:

https://youtu.be/DS2KNHdh9OI?t=46

You can hear how it loops. Anything shorter would just be more obvious. Compare that effect to a sine wave. Anything longer is less noticeable, also easier to mix in with other sounds or effects over time to make the loop less noticeable. Anything shorter sounds more like repetitive clicking.

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Right, so ballpark estimate here, how long should my sliding sound be? I don’t want to go track down another sound only to come up short again.

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I could give a few more examples (mirrors edge glass sliding, pipe sliding) but there isn’t a X amount of seconds per sound type. It depends on what is recorded. That tomb raider sample I sent is I think < 1 second, and this fits the game in its time, but might not fit yours. There will also be loops that are longer (rain, wind) in ambient music and games in general that can’t possibly fit within that time properly.

The best advise I can give if you look for a sound effect online, is that the provider of that effect allows you to preview (download) it so you can test it before buying a license for use. Even better if the provider sells looped sounds. If a sound ends different from how it starts, you might just have to cut half of it to hopefully get remotely close to creating a looping sound the hard way.

I’d like to think from the end user’s perspective. The sound is going to loop, that’s expected. It doesn’t have to be 20 seconds long. But most importantly, it should not be annoying to listen to, fit the overall sound design of your project, and fit the situation. Sounds can also be dynamically modified at runtime (pitch, volume etc.) within Unreal Engine to provide dynamics. An end user will not enjoy a sound of sliding on stone when the visual design is walking on mud. The balance is critical. Again, it’s most important to be allowed to test the sounds and have a library to pick from before spending money and time on it.

I’d definitely not go buying short (< 2 seconds) loose files without having selected them with a purpose. You’d be better off using samples cut from real recordings on youtube to test your sound design. You’d better be off buying a cheap mic to record them with materials found nearby.

A lot of sound artists actually create sound effects in a mic using materials you would not expect, but sound natural. It’s best to keep in mind that everything is designed with a goal in mind. You can find two packs on the internet that sound good initially but still sound wrong / weird when mixed and put in your project. That’s because they use different materials, techniques, hardware, mixing, quality with different goals (styles) in mind.

Testing this is crucial and I hope you find a way (perhaps a full sound pack, or by sampling youtube) that you can get a better idea of the whole.

If you are comfortable with command line, you can use an open source video downloader for samples to test with like:
Github: YTDL

I’d be very careful with the overall sound effect seller. Copyrighted and AI generated content is sold too often.

If you look for a mic, you can honestly often get away with the cheapest thing available. I use a somewhat expensive Blue Yeti mic which is very portable to take with you outside (usb connector, pop / fluff filter etc.) it’s tiny, clear and popular in the ASMR community as well.

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I meant how long does a sound need to be for it to be made loopable? Without hearing seams?

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A “seam” depends on content more than time. The seam (making a loop most noticable) is made less noticeable by blending it in with the content, optimally removing the seam entirely right?

So if you have a sound of 4 seconds of sliding down glass, 3 sec of which is somewhat loopable and 1 sec of glass squeaks, you loose 1 second at least. because you don’t want it to squeak on loop, it would be annoying. Now you look at the remaining 3 seconds. It’s somewhat loopable with a slight difference in pitch and the sound characteristics are scratchy with some environmental noise in between. Looping that is now a manual task either in audacity or other software and again depends on the sound to carefully make cuts in place or filter. Filters at this point (stretch, equalizer, reverb or any other) only damage the original data into blurred result. This particular sound effect (if you manage to loop it) went through a process which you can not apply to just any other. That is what I try to say :slight_smile: . That is why, with one sound you can get away with one second (the Tomb Raider 1 example), perhaps 4 to slide down a metal pipe, and perhaps 6 for a mud slide with some runtime sound modifications. I’d say, not longer than that. Unless you are working with a looping sound you hear constantly (wind, rain, tree leaves, city chatter, car sounds), they can be half a minute to minutes, or multiple effects randomized (but still sounding like a natural whole!). It depends

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You need a few seconds to loop without it being obvious.

Adding in the start and end, then you’re looking at 5 seconds upwards.

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