I'm currently trying to transcribe Come As You Are by Nirvana, for piano. I've got the melody right, but I'm struggling with the drum part, and without the beginning sounds it's really boring. Any tips?
There isn't a particular method. That's the art of arranging: you decide how one composition for a particular arrangement gets transformed to work effectively on other instruments.
This arrangement treats the verses as just bass and melody. You could take that as a queue that you don't necessarily need to rearrange the drum part, or at least not completely, and certainly not note for note (rhythmically speaking.)
If I were doing the arrangement, I would probably think of it in terms of what do the drums do in the original? A big part is timbre, tone color. Drums bring so much color from cymbals, snares, and all the ranges of toms, and all of that tonal color changes hugely through dynamics. You can't even come close to that timbral variety on a piano. But, there are also drum fills. Those server a more phrase structure purpose, filling in empty space of the melody, and leading from the end of one phrase to the start of another. Also, the drum serve as accents or doubling up with other parts. Often kick bass drum and bass work together, or snare and rhythm guitar might be in sync. You could try taking the drum fills and accents as queues for places to "dress up" your arrangement.
For example, in the intro to the song, you have the guitar solo for a few bars, then the floor tom is hit a few times as both a doubling of the guitar and as kind of fill, an anacrusis to lead into the next pattern repeat.
What could (could, not must) the piano do to fill that purpose? You could sort of "Mickey Mouse" it and hit some kind of low range tone cluster to "mimic" a low drum. (Not sure that would really work.) You could try some kind of glissando, that's much more a real piano effect to create a fill. Probably the safest thing to do is put a middle voice between the lower part from the guitar and the main melody and have it follow along with basic time keeping patterns - quarter notes/eighth notes, etc - which is part of what the original drums do, and then give some original countermelody/counterrhythm ideas to the inner voices along the rhythmic lines of the original drums.
In the original records you get three floor tom hits in the intro, then a light crash cymbal on beat one of the next bar. You could try something like a three note middle voice line leading up to a chord on the one beat and held (mimicking the crash cymbal.) That all happens while the left hand does the guitar arpeggio part.
Another quick idea. In the part where the lyrics is "memory" (of whatever he's mumbling) the drums do a lightly building roll. It's serving largely as a crescendo. The piano could do something like sixteenth note turn figures rising up the scale, or perhaps a tremolo on a chord of just an octave.
Don't be shy about jumping around the various registers of the piano, or breaking up the notes of several parts between the hands. On time, when I took a composition class, the teacher told me to stop treating the piano like a harpsichord. He wanted me to use the full range of the instrument, and one thing that will give you is more timbral color. In the end, you won't make your arrangement sound like the original recording. That should be obvious. The challenge of the arrangement is how to make it interesting piano music.
Totally of the top of my head, try listening to these few things, if you don't already know them...
- Gershwin's three piano preludes
- Prokofiev's piano toccata
In the case of the Gershwin stuff, I think the prelude convey the feel of a small jazz combo, also take note of the interesting syncopated accents throughout, and the Prokofiev is pure aggression. Both provide nice antidotes from "classical" piano, and may give you ideas about how to arrange rock music for piano without it having the feel of Muzak.
In the case of a "boom-chick" part like this one, I use a low octave for the "boom" and mid-range chords for the "chick". The low octave imitates the kick drum, and the mid-range chords (played staccato) give the feel of a high-hat. The combination provide the sort of rhythmic drive the drums provide.
For this song specifically
- on the downbeats, I'd double the bass an octave lower;
- on beats two and four I'd play whatever the prevailing chord is.