?A heat sink / processor fan will sit on top of your processor and it's job is to keep the processor from burning up. Most processors can make it only a few seconds without the fan / heat sink to keep them cool. For a recording computer, I would not cut corners here. You will find drastically different levels of noise in a heat sink / fan combo. Most fans and such have noise ratings. Find the lowest amount of noise as possible for your budget.

While I said that I wouldn't recommend any brands, Antec, seams to be one of the top brands for finding a quiet heat sink. There are probably others that you should research too, but Antec usually has some unorthodox designs that will give you some insight as to where you should start your research.

As long as a heat sink / fan is quiet and does it's job, there really isn't THAT much thought that should be put into it. Just get the quietest heat sink / fan you can afford.

Also keep in mind that the bigger the band, the lower the RPM required. This means the lower the noise. So if you have the option of using a larger fan with a heat sink, always do it.