Sound Design Workshop: Beat the Blahs

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FIG. 1: When a REX file is loaded into the Reason NN-XT sampler, each slice will be assigned to a separate key. Use the Out knob (middle right of graphic) to assign slices to various audio outputs, such as the 5-6 stereo pair (shown here).

For fifty or a hundred dollars, you can buy a CD or DVD that's packed with great-sounding, professionally designed drum loops. But sometimes a beat needs a little work to sit well in your mix. And if you use it just the way it is, there's always the remote chance that someone else might use the same beat in their song that you use in yours, which would be embarrassing. Also, creative sound design is so easy and so much fun that it would be a shame not to take a few minutes to shake, rattle, and roll that beat into something new.

In this column, I'll show you how to slice and dice a beat and then run it through a vocoder. If you have Propellerhead Reason 4, download and run Mangling_2.rns, which contains both the slicer and vocoder patches (see Web Clip 1).


If you use Reason, you already know how to load REX files into the Dr.REX module. But Dr.REX is rather simple. You can do much more with a REX file by loading it into Reason's NN-XT sampler module.

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This trick works with files from the Reason library and with third-party REX files. First, load the file into Dr.REX, and then use the To Track button to extract the MIDI data from the file. Next, create an NN-XT and load the same file into it. Drag the MIDI data from the Dr.REX track into the NN-XT track.

Now delete the Dr.REX and listen to the sliced-up beat as it's played by the NN-XT. It should sound just the way it did before.

Open the NN-XT Editor panel (see Fig. 1). Click on the Select Zone Via MIDI button, and play up and down your keyboard. By doing this, you can quickly identify the zones that trigger the snare, kick, and other samples. Use the Out knob at the right end of the row below the display to assign the kick and snare samples to their own output channels (such as 3-4 and 5-6).

Route each of the three types of sounds (kick, snare, and hats/other) into a different Scream distortion unit. Cable the outputs of the three Screams into a line mixer, and start fiddling with the parameters of the Screams. I got good results by applying a tube algorithm to the kick, ring modulation to the snare, and overdrive to the hats.

You can do a lot more with this type of patch. Adding stereo delay to the snare using separate DDL-1 units for the left and right sides is a trick I often use (see Web Clip 2). Try replacing single samples in the beat with other types of audio, or apply NN-XT's filter and envelopes to them.

Try splitting one sample (such as the kick on the downbeat) to a different output and sending it to a delay. Add a couple of high-feedback CF-101 Chorus/Flanger modules to the input or output of the delay, and throw a Scream in somewhere to add overtones to the signal (see Web Clip 3).


Although adding vocal tracks to Reason songs is technically possible, it isn't easy — so why does Reason have a vocoder? One good application for this module is to use a Dr.REX beat as a modulator. Patch the Dr.REX left output to the vocoder's Modulator input, send the output of a Malström or Subtractor to the Carrier input, play sustained chords, and then start the beat. Instead of hearing a drum loop, you'll hear pulsing rhythmic chords (see Web Clip 4).

It's important to use a harmonically rich sound (such as a Subtractor sawtooth wave or the Malström FemaleChoir waveform) as the carrier, because a vocoder only subtracts partials from the signal; it can't add any. A beat that includes both low-frequency and high-frequency components will give the pulsing chords more variety.

Try turning up the vocoder's Decay knob a bit so the sound is more flowing, or turn it down for a choppy rhythm. Better still, tuck the whole patch into a Combinator, assign Rotary 1 to control the vocoder's Decay knob, and patch a synced sawtooth LFO from a Subtractor to the Rotary 1 rear-panel CV input. The decay time will change every bar or two depending on the speed of the LFO.

Jim Aikin ( writes about music technology, teaches cello, and also writes various sorts of fiction.