Drums in the box: sequence and control

While I am sequencing with the Tchimera Drum Kit in a process of migration from the Flac_GSCW-2 drumkit in Hydrogen, I realized that the open hihat rather sounds like a half-open one. I listened to the samples and found open hihat sounds. However, some control parameter seemed to be set with a default value that triggers the sample of a half-open snare.

Long story short

The short story is that the MIDI continuous controller (CC) #4 determines the position of the hihat pedal—with 0 fully open and 127 closed—and defaults to a more closed value of 100. A clue to this was the opcode¹ set_cc4 in the hihat.sfz file and the explanation in Michael Willis’ announcement². Using MIDI CC 4 to control the degree of hihat openness appears to be “the common pedal assignment in electronic drum kits” according to sfz format documentation on cymbal muting.

You may be laughing if you learned to sequence drums with mute groups and MIDI CC assignments in the first place. However, as I autodidactically explored this realm with Hydrogen and Flac_GSCW-2 before sitting on the stool, I was unaware of such MIDI capabilities and intuitively worked around such constraints. I guess that this has contributed to the way I am writing a drums score. Hence, I recap some of the lessons I have learned along the way in this post.

Choosing a drum kit

The primary and one of the most important things about working with drums “in the box” is to choose a drum kit that already provides a good foundation for the sound you imagine. For example, I was soon disappointed by the default GMRockKit and TR808EmulationKit supplied with Hydrogen. It lacks a second crash cymbal and some samples seemed to be faded out prematurely in order to reduce the file size. Moreover, there are no more than five layers to reflect the dynamic range without alternative samples to avoid the sounding like a machine gun in snare fills.

For this reason, I soon moved to try other drumkits provided through the sound library import³ function. When I started my digital drums journey back in 2010, there were about 10–15 Hydrogen drumkits available and I chose one depending on the song. Without being aware of concepts such as MIDI CC, I settled on using Flac_GSCW-2, as it provides choked crash cymbals and snare and tom flams. Though I wondered why an open hihat is muted by a following closed one in TuxGuitar’s output, and realized that a flam is written as a grace note—which means that it can be produced manually through triggering the same note twice—I lived with that.

Anyways, the point is that you get started with a drumkit that works for you. And from my experience, this may involve using an out-of-spec drumkit and learning about some technical details later. I wish they would’ve taught us these internals during my academic course, but don’t get me started talking about all the issues of surviving at an university of applied sciences that offers product training rather than sovereign education⁴. ¯\_(ツ)_/¯

Make use of velocity

Another crucial element of a drums groove is to change the velocity of individual notes to add variation and make it sound more human. Hydrogen has velocity lane below the pattern grid and Ardour just implemented “lollipos” in its velocity lane with the release of version 8.1⁵. It’s a matter of listening experience combined with intentional rule violation to create interest while keeping the human feel. Try to think like a drummer: You cannot keep the exact same velocity throughout a couple of bars and accentuate certain beats to support the groove.

To keep things simple, consider the example “bum tchak bum bum tchak” pattern I introduced in my first post about scorewriting and reduced to kick drum (note 35) and snare (note 38) only. The > and ^ signs mark an accentuated and heavy accentuated note on the kick drum to make the 1/4 and 3/4 beat stand out of the sound, as typical for a four-four time bar. However, I could also only accentuate the last kick drum to draw attention to another beat.

C|---------------------------------|
C|---------------------------------|
C|---------------------------------|
C|---------38--------------38------|
C|---------------------------------|
C|-35--------------35--35----------|
   ^               >

It depends on what is happening in the arrangement and how the drums are used in a song. Simultaneously, keep in mind what a human drummer is able to play. Of course, you might want to violate that rule and have drums that are interesting due to being difficult to play by a human. Over time you will learn how to groove your way.

Human patterns

I like to scorewrite drums and create patterns that a human would be able to play. Though it’s fun to experiment with the opposite and push the limits, human patterns work better for my style of music. Consequently, I also keep the “think like a drummer” law in mind for simultaneously hit individual instruments. A human drummer has two arms and feet. For this reason, four instruments can be played at a time (e.g., kick drum, closed hihat, and snare). This means that the following example snare fill is more of a drummer’s fantasy:

C|-57--57--57--57--57--57--57--57--|
C|-51--51--51--51--51--51--51--51--|
C|-46--46--46--46--46--46--46--46--|
C|-38--38--38--38--38--38--38--38--|
C|-45--45--45--45--45--45--45--45--|
C|-35--35--35--35--35--35--35--35--|

For explanation, the notes in addition to kick drum and snare are 45 = high tom, 46 = open hihat, 51 = cymbal (left), 57 = crash (right). A drummer would need five arms to play this bar. If this is your style, go for it. Similarly, you may come up with a pattern full of 64th notes and a tempo of 360 bpm, but I doubt that even an advanced listener is able to identify each single hit. Don’t get me wrong, experiment and push the limits. It’s just not my style.

Leveraging continous control

To conclude my comments on drums sequencing, let’s get back to the new technical detail that I learned recently: continuous control. Using this value, the different levels of openness of a hihat can be controlled. For example, consider a hihat that transitions from rather closed to full open over half a bar just before a chorus in the song. The image below illustrates how a course of automation values would look like to gradually release the foot pedal.

I will experiment with CC for the hihat openness and groove my way along the planned album. I guess the next thing to learn is polyphonic aftertouch AKA channel pressure⁶ and this is used to choke cymbals.