Desmond is spot on with his assessment...
A 'sample' is a recording of a sound. Someone might not own (or need to own) the copyright of the sound (if there is one) but they own the copyright on the 'recording'.
That is why you can sample an analogue synth or a piano or a guitar freely but you cannot sample a ROMpler or a sample library or a sample based drum machine, whatever.
So you can sample a real piano but you can't sample a digital piano. And if you sample a real piano, you (technically) hold the copyright on those samples/recordings and if someone else nicks them and re-distributes them (even if they modify them), you can wallop them. But if you sample a Clavinova, Yamaha can wallop you ... but they can't if you sample their C7 acoustic grand!
Technically speaking, you can sample the kick and snare of a TR909 (analogue) but you can't sample its toms, hi-hat and cymbals (samples).
But you can freely sample an entire TR808 (all analogue) and you can sell them or give them away but, technically, you cannot call them "Roland TR808" because that is exploitation of a registered trade name which can also be copyrighted and Roland can have your arse and have your work withdrawn if you did make a "Definitive Roland TR808" soundset ... but you could call it "Ultimate Dance Beatbox" or somesuch without any problems.
You may remember a little upset a while back when all Fender Rhodes library suddenly disappeared and returned with a new name ("Classic EP", whatever). This is because someone bought the Rhodes trademark and objected to the name being used on sampled products from the likes of Scarbee, etc., even though it is perfectly legal to sample the sound!
But there are grey areas... sample based products long discontinued where the manufacturer no longer exists and the samples/recordings are of no commercial interest to the original copyright holders (if they still exist), for example, are fair game. There's a chance that someone might come out of nowhere and say "Oi! That's my copyright - cease and desist" but it's unlikely (and as I have experienced, some can actually be grateful for resurrecting some of their lost 'children' .. so to speak).
However, others are much stricter. Roland, for example, forbid the sampling of their old drum machines because they still hold copyright and they may want to use them in a new product of theirs. Which is fair enough. So sampling and re-distributing their TR707 is a no-no. But Roger Linn's probably not bothered about his old LM1 and 2 being sampled (even though, technically, he could object and be within his rights to). But even if he doesn't object to those old 8-bit drum sounds being sampled, he MIGHT object to his tradename being used. Or might not... depends if he thinks it benefits him and his current products - which it might. More specifically, it depends whether the usage tarnishes his name/professional reputation and that is a big concern for trademark owners...
These CDs flogged on eBay that the seller advises is a 'must-have' are a case in point.
Yeah! Right! A single sample from each sound, badly recorded, badly looped (if at all) and sounding like utter shite and totally unusable. That (potentially) tarnishes the professional reputation of the original manufacturers/copyright holders and the seller can be hammered on so many levels (if eBay gave a sh!t about copyright that is!).
There's also something called "Unfair Competition".
For example, I get a MiniMoog Voyager in and I multi-sample its presets extensively, one sample for very note - maybe even multi-velocity samples for every note - using long samples that breathe and evolve. I spend time carefully programming everything so that it is, to all intents and purposes, indistinguishable from the original Voyager and I put that on sale for $50. A bargain. All the presets from a Voyager for 50 bucks. Wow!
Even though it is perfectly legal to sample an analogue synth such as the Voyager, Moog could rightly claim "unfair competition" in a court of law and would probably win because their £1,200 products' sales are quite likely to be affected by my $50 soundset. They could also have a claim that the settings used for the various presets are (effectively) their copyright ... which would probably be supported.
However...
I could sample the presets from a Prophet 5 without any real danger of litigation.
Now, I could get a Voyager in and sample sounds I create myself on the Moog and also avoid litigation. But if I 'exploit' the Moog trademark to add kudos to my soundset (i.e. "Ultimate Moog Voyager") to enhance my sales, Moog could get stroppy ... and rightly so - "unfair competition" again. But I could sell it as "Ultimate Analogue" without risk ... whilst running the risk of not selling any because the 'Moog' name is not exploited to give the library credibility ... it's just a.n.other analogue synth lib and there are loads of those out there - it would be the 'Moog Voyager' tag that would make it desirable.
Similarly Doepfer, whoever. Even though their modular systems have no presets (obviously), Doepfer would be within their rights if I released a 3GB DVD of Doepfer sounds I created from scratch for $150 called "Definitive Doepfer" on the same grounds - exploiting their trademark/brandname to add kudos to my product and enhance my sales and potentially troubling theirs ... "unfair competition". But I could release it if I called it "Definitive Modular".
It's a bit of a minefield but to be honest, a lot of this is just common sense. I just wouldn't make a comprehensive library of Voyager sounds on moral grounds (even though I could probably make a pot of money) because Moog (and Doepfer, whoever) deserve respect and I wouldn't want to do anything that might jeopardise their sales. I could have sampled the crap out of a DSI 'Evolver' a while back and released it as a product but that would be unfair to Dave Smith.
On the other hand, I would have no moral turpitude sampling the crap out of a Prophet 5 extensively.
Do you see what I mean?
Basically...
You can sample a Roland Jupiter 8 freely and without restriction but if you are going to sell it or give it away, whatever, you cannot use Roland's trademarks
You CANNOT sample a Roland Fantom because the sounds utilise copyrighted 'recordings'. Well...
technically you can't - you certainly can't sell it carrying Roland's trademarks
However, you could combine and splice and merge samples from a Jupiter 8 with your own programs from, say, a Korg Trinity or whatever to create something totally new and that would be ok - but not if you tried to sell it using any of the manufacturers' trademarks. It is unlikely that such a commercial soundset would fall foul of the original samples' copyright holder(s) (although it could in theory) because they're on the lookout for more blatant contraventions.
If all this seems confusing and draconian when sampling ROMplers, think of it another way...
You wouldn't buy a product that had sampled, say, the Garritan Orchestra sample library and which was called 'Ultimate Garritan'. You would immediately think "Wow - what a f'cking ripoff ... selling someone else's samples? That's terrible" ... but it's the same for ROMplers - selling someone else's samples!
Of course, there is a way around this ...
Get permission!
At the end of the day, apart from an understanding of copyright law (essential in this business), a moral compass is also required. Sadly, some peoples' are pointing south!
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