19.2. Creating a New Instrument

For each instrument in a drum kit, you can load several samples and set different synthesizer parameters. This section will step you through how to create a new instrument and load the samples. For details about the individual parameters please refer to Section 11.1.

To begin creating an instrument, select InstrumentsAdd instrument. This will give you a blank instrument to start from.

Now, you need two samples. Any .WAV or .FLAC file will do. Hydrogen provides several in the data/drumkits folder in the Hydrogen data directory (usually $HOME/.hydrogen/data/).

In the Instrument Editor, click on Layers. You can layer several samples into the instrument. Which one is played depends on the velocity of the incoming note. Click Grey button containing the black characters "LOAD LAYER". and point the Audio File Browser to your sample.


The Audio File Browser will allow you to preview the sample before you load it. It will also allow you to load more than one sample at a time. But for now, only load one.

After you load the sample, you'll see that there is now a 1 at the top, and the topmost rectangle has turned light blue. To load a second sample, click the slot just below it, and then click Grey button containing the black characters "LOAD LAYER". to bring in another sample.

After bringing in both samples, you'll probably notice that only the first sample is being played whenever you trigger the instrument. This is because you need to set the velocity ranges for the layers. Move your mouse to the sides of the light blue rectangles and you see that you get a left-right drag cursor. Now drag the sample to the left or right (like a curtain). You will now see Layer 2 appear.

The velocity setting for the layer is 0-velocity on the left, and full velocity on the right. Set up Layer 1 to sound for soft notes, and Layer 2 to sound for hard notes, i.e. Layer 1 on the left and Layer 2 on the right (see Sample Selection for further info).

Now, in the Drumkit Editor, set up a simple pattern that plays this instrument. Adjust the velocity settings on each note in the Note Properties Editor so that you can get the different samples to sound. Now, set the playback to loop and notice how your different samples are getting triggered. To learn about editing a pattern, see Chapter 9.

For each layer, you can set the Gain and the Pitch. The pitch also has a Fine adjustment.

Use the Gain adjustment to control how loud the sample will be played. This is necessary because it's extremely difficult to get a set of samples that all sound at about the same volume. By adjusting here, the samples that were recorded too quietly can be turned up to match your loud samples (that had to be turned down).


It is very easy to set the Gain too high, causing your sample to clip. Remember to test the gain with full-velocity using the Grey button with a filled black triangle pointing to the right. button in the corresponding Instrument Channel Strip. If you clip your signal here, it will only get worse as Hydrogen processes it.

The pitch of the sample can be modified with the pitch controls. The Pitch knob adjust the pitch in musical half-steps. (So, -12 is down 1 octave). The pitch on the right adjusts the pitch ±50 cents. (One half-step is 100 cents.)


The pitch is adjusted by playing the sample back faster or slower. This is called the Doppler Effect. So, if you have a 1-second sample that you turn down 12 (1 octave), your sample will only last for 0.5-seconds. If you do not want this to happen you should use Rubber Band instead (see Section 12.2)

You can hear the sample in a layer by clicking the layer id (just below the 'General' and 'Layers' buttons).