I have a few specific questions/examples about sampling music and the legality of certain techniques.

Example 1:
I sample a one bar guitar riff from an artist's song.  I loop the entire one bar guitar riff, and add my own drum pattern.
-Is this copyright infringement? (the answer should be yes)

Example 2:
I sample a one bar guitar riff from an artist's song.  I chop the guitar riff into two parts, and reverse the order in which the parts are played. Then, I add my own drum pattern.
-Is this copyright infringement?

Example 3:
I sample a one bar guitar riff from an artist's song.  I chop the guitar riff into FOUR parts, and reverse the order in which the parts are played.  I then add a phaser effect to the guitar part, and EQ out all of the high end, leaving only bass and mid range frequencies.  Then, I add my own drum pattern.
-Is this copyright infringement?

Yes

Yes

and Yes

As soon as you take someone elses work and use it, it's a copyright infringement no matter how short or what you do whit it. (If you brutally mangle it it beyond recognition, it's still a copyright infringement, even if no one will ever know about it.)

Also there are two sets of rights you need to clear. Firstly the right to use someone elses composition (i.e. the songwriter) and then you will also need to clear the usage of that specific recording of the song (same song can be recorded by multiple artist and/or at multiple sessions)

you only need 2 clear samples if u plan on selling them

^not technically, you only have to worry about clearing samples if u plan on selling them. but if there 'published' somehow then you should clear.
otherwise i could sample a michael jackson song, and by sample i mean take in its entirity and not chnage at all. then put it on the internet, and say its not copyright infringement as im not selling it

so lets say u sampled something from a big producer, how do u contact him? and what if i sell that beat... is it still my responsibility to clear that sample or the artist thats bought the beat!

As far as copyright infringement goes i would not cross that bridge until i know my ish is 100% gonna make some noise and then an only then would that be an issue. If i did make something and it was being looked at for radio or cd just major play period i would be glad to let the world know what i used and how i did it to me it is all a part of the fun or creativity word." Of course after the samples clear!!!"

I just don't understand how so many sampling producers can exist in the world of hiphop if that is the case.. there's a ton of  labels that have producers who sample... and there is no way that most of these producers are obtaining sample clearances for every single .wav  they use in their music.

How many units would you need to move before you expect someone to come after you? I mean really... I want a number.

I mean, does the radio or television really set the standard for it anymore either?  Theres people that are selling a ish load of music and they aren't on the radio...  is anyone coming after those people?

@R&P prod. Theres clearing houses that can go about the business of getting samples cleared for you for personal things. Will set you back about $500-$1000 for the priviledge though. Or if your dealing with a record label at all, they will have their contacts. As for whos responsibility it is, I'm not really sure tbh, some people say its the producer, some say the rapper. i'd say whoever is said to be publishing the music (i.e. 'putting it out') has responsibility. So if your putting beats on soundclick, thats your responsibility. If you've sold it to a rapper who's then put it on a mixtape or something just to sell to those in his neighbourhood, then its probably up to him. But as said before, unless your making money from it, no-ones coming after you. And the only way your really making money off it is through a label, and then they will handle it.

@Sage. I think you may be confusing samples as in any sound that has been recorded or created (for example, the stock kits in FL) and a sample as the creative basis of a song. The first, whilst you may have to clear (many many are royalty free etc), no-one is ever gonna know or be able to prove that you used Kick1002-Bassy from a kit you found online. Even if you chopped a snare from a james brown break, it would be very hard to prove that its the same snare, so much so its not worth persuing.

As for samples as the basis of a record, like sampling a soul record. Then the sample will be cleared unless someone like madlib or black milk has gone to work on it so you couldnt tell the sample. But if its being published and sold by a label, it'll be cleared, or it wont be cleared and theyll be sued.

As for units, who knows. Someone could come after you anytime, even if you've just sold one mixtape with a sample on. I suppose you have to ask, what level of units or what level of exposure can you achieve before someone who cares notices that you've used a sample. 2nd question would have to be, is it then worth their while to come after you. Even if you've sold a thousand and made a bit, is it worth the legal fees and hassle to claim a portion of that thousand back?

okay...

what about samples downloaded at this website????
or
if i take a single note from a song, thene make my own melody wit it???

and what if someone uses the same bass line or, melody using a difrent instrument??

If you took a single note from a song, chances are it wouldn't be recognized as far as where it come from. If you recreate the same melody within your record, your are not using the recording at question. A lot of main stream songs emulate other mainstream songs with no type of clearing. For example, drum patterns are used over and over. No one has the right to a particular drum pattern. There really is no fine line but you cant just remake a whole pre-existing song and get away with it. Once again, as mentioned earlier in this post, if you are doing it just for your personal enjoyment then you are ok. If money is made (not just by you but by anyone) then there will be problems.

yeh, theres no way you can get in trouble for sampling drum patterns. and sounds on VST plugins because you dont own them.