KICKS, CLAPS AND HATS ...

RUMBLE KICK

The first new model is the so-called 'rumble kick', a classic right out of the Techno production bag of tricks.

To make a techno track sound 'huge', it can be interesting at first sight to put a reverb on it, to sound like it's played in a large club or dance hall. However, this may quickly start sounding very 'muddy' as the kicks only poorly stand out against the background of reverb. So, to not interfere too much with the main kick sound, this reverb sound is then made to 'duck' to to the kickdrum sound, using a compressor.

Secondly, to separate it from other rhythmical elements in higher frequencies, the reverb is often lowpass filtered, eventually after some distortion stage.

That's the basic trick. The result is a kickdrum sound followed by a low reverb rumble that gives it a huge, spacious feeling and eventually some bassy afterbeat groove.

We integrated this complete scheme into a single kickdrum model on the DR-2.

• A sinewave oscillator is controlled by the pitch and amp envelopes, to generate the basic kick sound.
• The result can eventually be distorted somewhat with the Z-parameter.
• This dry kick sound is then fed into a reverb-distortion-lowpass sequence to create the rumble, the lowpass filtering frequency can be set with the Y-parameter.
• An envelope generator then simulates the ducking process. The X-parameter determines the delay time between the start of the kick sound and the moment the reverb tail comes in.
• The T-parameter finally, sets the balance between the dry kick sound and the reverb tail.

A little remark here: it's also possible to use only the dry signal, this kick drum model is also very usable without the reverb tail!

FILTER HIHATS

The original hihats model of the DR-2 is a nice but quite general sounding algorithm. With this new 'filter hihats' model we're using some less ordinary filter techniques to create a bit more 'edgy' sounding hihats.

This hihat synthesis algorithm works again with a mix of so-called 'cymbal noise', a set of 8 harmonically unrelated square wave generators, and pink noise, created out of white noise with a ~3dB/oct low boost filter. A mix of these two is fed into a lowpass and a hipass filter in series with adjustable filter slopes, from 0dB/oct -no filtering at all- to 84dB/oct, in steps of 12dB/oct.

Thanks to the filtering with steep filter slopes it can be very easy to put these hihats in their own, well separated frequency range.

• The T-parameter sets the balance between cymbal noise and pink noise
• The Z-parameter controls the spectral content of the cymbal noise
• The pitch parameters determine the central filtering frequency
• The X-parameter sets the slope of both filters, in steps of 12dB/octave to 0, 12, 24, 36, 48, 60, 72 or 84dB/oct
• The Y-parameter sets the distance between the lowpass and hipass filter frequencies, or the 'bandwidth'

FILTER CLAPS

The original claps model of the DR-2 has a simple design, that sounds, let's say, rather 'electronic'. More like the sound of claps found on many vintage drum machines, than the actual sound of a real person clapping his hands.

At the time those vintage drummachines were built, they made an effort to mimick the sound of a group of people clapping by using bandpass filtered noise. Repeated short attacks were added at the start of the sound to mimic a group of people clapping almost, but not entirely simultaneous.

Later on, this became the standard 'claps' sound, and only little attempts were made into further refinement of the sound.

Though it didn't prove very complex to do so... When we put a few samples of real world flamenco 'palmas' performers in a frequency analyser, it became immediately obvious that the typical bandpass filtered noise is not a good reproduction of a real handclap. In real handclap sounds, the lower frequency roll-off is rather gentle, around 6dB/oct. But the higher frequencies, above 1kHz or so, roll off at a very steep slope, with 48dB/oct or even more.

That brought us to the next handclap synthesis algorithm:

• A white noise oscillator is filtered around a central frequency set by the pitch parameters
• The frequencies below it are filtered with a highpass filter of which the X-parameter determines the slope in steps of 6dB/oct to 0, 6, 12 or 18dB/oct
• The frequencies above it are filtered with a lowpass filter of which the Y-parameter determines the slope in steps of 12dB/oct to 12, 24, 36, 48, 60, 72, 84 or 96dB/oct
• The Z and T parameters control the number and time of amp envelope retriggers, identical to our classic claps model

So, it is possible to set both the lowpass and highpass filter slopes separately. Steep slopes on the lowpass filter (higher values of X) and a more gentle slope on the hipass (lower values of Y) produce quite realistic handclapping sounds, though other slope combinations are equally possible.

EXTRA PARAMETRIC EQUALISATION STAGE ...

But then, especially while designing our new Rumble BD model, we felt again that it is highly desirable to remove a certain frequency range in the lower mids to make real good, punchy electronic kicks.

In the Square BD model, this was already partially addressed with the notch filter stage of this model. We could have built in such notch filter stage again in the Rumble BD, but we thought there was another, more general option to do this.

We added an extra parametric equalisation stage in the 'after treatment' section such that every instrument can benefit of the possibility of boosting/reducing a certain frequency range.

Reminder: The after treatment section is the sequence of a distortion, this new parametric equaliser, a tilt filter and a compressor that each of the 6 instrument slots has to further finish the sounds created by the synthesis models.

So, each of the 6 instrument slots now gets this extra equalisation stage between the distortion and the tilt filter, with:

• A frequency parameter with a range from 0-12kHz [0-127], controlled with SHIFT+DECAY in the pitch section
• A gain parameter that can be set between -36dB and +36dB [-64-63], controlled with SHIFT+CURVE in the pitch section
• A Q parameter that can be set between ~+∞ and 0.25 [0-127], controlled with SHIFT+AMOUNT in the pitch section