The KENDANG (drums) act as leader of most Gamelan ensembles, helping to establish the speed and energy of a piece. Just like KOTEKAN interlocking on GANGSA, there are usually two different rhythmic parts made to fit together to achieve a speed and complexity which would be difficult for one player alone. By altering their repeated grooves the drummers give signals for changes in volume, tempo, and cues to ANGSEL breaks.
Check out the start of the GILAK video below, even if you don't have any kind of drum to practise on at home, because it's important for everyone in the ensemble to recognise the sound of these basic rhythms. The knee-tapping exercise is quite good at giving you a feel for the GILAK pattern, which is used in many of the tunes we play.
The next most common groove you'll get to know is BATU-BATU. Technically this is the name of a semi-improvised style of paired drumming but it's very common to play fixed versions to begin with. Also this particular version of BATU-BATU is said to be appropriate for the tunes WIRA YUDHA and CRUCKCUK PUNYAH. Of course drummers like to mix things up a bit and have fun, so as long as the rest of the ensemble is prepared for a little variation, the drummers have a certain amount of freedom. (More about BATU-BATU variations in later videos...)
Learning the names of the various drum strokes enables us to communicate the patterns vocally, as they do in Bali, and gives you another way to practise. In CEDUGAN drumming, which uses PANGGUL (sticks) to play the KENDANG the sounds are "DAG", "TAT", and "KAP" for the WADON. LANANG has the sounds "DUG", "TET", and "PAK". So, for example, we can recite the slow section of CRUKCUK thus:
Dag _ Dug _ Dag _ Dug _ Dag _ d'Dug _ KaPaKaPak d'DaDuDag _ d'Dug _ KaPaKaPak d'DaDu
Dag _ Dug _ Dag _ Dug _ Dag _ DuDaDug _ Dag _ Dug _ Tat _ Tet _ Dag _ Dug _ DaDuDag _ Dug _
To quote a great book *DON'T PANIC* about the example above. You're not supposed to learn it from the written words, but it sort of sounds like that once you have learned it.
Maybe an example from these videos would be better. Here's the PINDAH_PINDAH 'swapping bar' of BATU-BATU:
_ Ka Pa Ka Pa Ka Pa Da Du Da Dug _ Da Du Da Dug
If you've mastered all the WADON parts above you should try adding the LANANG patterns to your vocabulary. It's surprising how much better your WADON rhythm will feel once you've learned both halves.