It was recommended to me that I tune kick‑drum samples to the key of my song, so I used a tuner and an analyser on my stereo master and soloed the kick-drum track. The tuner said that it was playing an Eb at 78Hz. As my song was in Bb, I used a pitch‑shifter to tune the kick drum down to Bb, but it sounded really bad. What's the right way to go about this in a digital environment? I appreciate that I could just use my ears, but I'm interested in it from a technical perspective.
Via SOS web site
SOS contributor Mike Senior replies: The discussion of drum tuning tends to receive most coverage with regard to live kits and band recording, but the same kinds of issues also apply for kits in hip‑hop, R&B, and indeed any other style based heavily on programmed drum samples. If any drum sample has a prominent pitched element to its sound, there is the potential for that pitch to conflict with the harmonies of the production as a whole, and if there's a clash, the pitch of the drum sound in question won't tend to blend as well with the mix. This isn't necessarily a problem — and in some cases it can help the drum sound poke out of the mix and remain more up‑front. However, if you do match the drum sample's pitch to a note that blends into the track, that causes the pitched element to be masked by the other instruments in the track better, so its pitched component becomes less noticeable. This means that you can often mix the drum higher in the balance, thereby emphasising the noisier elements of the sound and making the drum feel punchier. So, to some extent, drum tuning is an artistic decision as much as a technical one. With kick-drum samples specifically, however, there is the added issue that many powerful‑sounding electronic kick drums (most notably the Roland TR808 kick) incorporate a very prominent, pitched, sub‑bass tone, and this will almost always make a mess of your song's harmonies if it doesn't fit in with the key, so it's usually safest to tune it to the key note.
Pitch‑shifting isn't the way to do this, though, because even the best pitch‑shifters tend to compromise the attack of percussive sounds. It's much better to simply speed up or slow down the sample's audio as a traditional sampler might do. There's a way to do this with the audio editing tools in most sequencers as well, but failing that you could import the sound into a dedicated hardware or software sampler and adjust it from there. Yes, the tone of the drum will change, but you won't get the kinds of nasty, flammy artifacts you'll get from a pitch‑shifter. I also wouldn't trust a tuner to reliably report the perceived pitch of a drum sound. Pitch‑detection algorithms are pretty good, but they won't always agree with what you're actually hearing. Trust your ears.
The simple answer to the question of how the lowest frequencies of the kick combine with those of the bass is: they don't! In almost all cases, one of them gives way to the other to avoid exactly the kinds of problems you're anticipating. With 808‑style kicks, you may even want to high‑pass filter the bass line to keep low‑end sludginess at bay. In the case where the bass has the sub frequencies, the kick can often be surprisingly light sounding, but you usually won't notice because it never actually appears in the arrangement without the bass.