It depends. What type of samples are you looking for ?
As DJ Cheeku said, you can check Looperman if you’re searching for drums/synths loops, impacts, up and downlifters… It’s one of the most famous websites. You can buy Vengeance loops if you also want drum samples & loops but they’re quite expensive AND overused by a lot of producers nowadays…
As a producer I like thesample.net there are some good free sample packs and freesound.org has a lot of great free samples too !
Hope you’ll find what you’re looking for ! 🙂
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