Latest / Electronic Music / Using Effects Pedals With Synths
Transcript
- Hello, I'm Paul White, and in this Sound On Sound podcast, I'll be looking at ways to use effects pedals in a modular synth system. Effects pedals are generally associated with guitars, but there's no reason not to use them with synths and in the case of modular synths, a pedal can usually be considered as just another module. For this podcast, I've chosen a deliberately bland filtered sawtooth sound for most of the examples, just to show you the kind of difference a pedal can make. Now keyboard synths and rack modules can usually be plugged straight into a guitar pedal. The modular synths with particularly hot outputs and may need to be turned down to avoid overloading the pedal and causing unwanted distortion. How much headroom's available varies from one pedal to another, but most pedals are designed to accept guitar signal levels which are typically just a couple of volts peak to peak. If the module in question doesn't have a level control for the output, you can still attenuate the signal by using a passive volume pedal, or you could make your own attenuator using a 250k log pot and a couple of sockets. Of course you can use effects pedals with any synth, but with a modular system you have the luxury of deciding where to place your pedal in the signal chain and the results often vary quite significantly depending whereabouts in the chain you put your pedal. Now delay is a very obvious effect to start off with, and there are many pedals to choose from, though one with a tap tempo facility makes it easier to get the repeat sitting in time with your music. If you put the delay pedal after your filter and envelope shaper, you'll add echoes to whatever sound you've set up. But if you were to place a delay, for example, between the oscillator and the filters, the repeats will change in sound along with the filter opening and closing. The level of any repeats will also be affected by your envelope shaper settings. Alternatively, you could use a reverb pedal to give you a sense of space, but without the rhythmic repeats of a delay. Here's the same synth part again, but this time using a whole reverb. While a basic reverb always sounds good, one of my favourite variations is to use the so called shimmer reverb, where the reverb is pitched up an octave higher than the input and this produces a sound almost like a string machine sitting behind your synth patch. Some shimmer reverbs allow you to use pitch shift intervals other than an octave, so try setting intervals such as an octave down, fourths or musical fifths. I'm also a big fan of the Strymon Cloudburst pedal. It's a kind of shimmer reverb but it adds a lot of complex harmonics and it sounds more orchestral than most. Using a guitar overdrive pedal or a fuzz box is also an easy way to give your basic oscillator waveform more attitude. It also gives the filter more harmonics to chew on. Overdrive can also be used to allow you to mimic guitar solos, especially if you're handy with your pitch bend and mod wheels. Again you'll hear a very different result depending on whether your distortion pedal goes before the filter or after it. For this next example I dialled in a little oscillator sub octave before feeding it into the distortion pedal and that gives it a really beefy sound. The distortion comes after the filter, which in this case was just set to take a slight edge off the oscillator. Large modular systems invariably include multiple tone oscillators, but you can also use a basic pitch shifter pedal to create the impression of two oscillators playing at the same time. A few cents of pitch change will create a detuned dual oscillator unison kind of effect, whereas intervals such as octaves, fourths and fifths are also useful. Some budget pitch shifters can sound quite glitchy on polyphonic sounds but even the cheaper ones tend to behave quite well when dealing with a monophonic source such as a synthesiser oscillator. If you plan to combine overdrive with pitch shifting then I'd suggest that you'll get the most predictable results by putting the pitch shifter before the overdrive, as I have in the next example. Another way to beef up your oscillator sound is to use a modulation pedal. A standard chorus pedal gives you another way to create the illusion of two or more oscillators that are just fractionally detuned. When using a square wave oscillator the effect that you get from chorus is not unlike pulse width modulation. Chorus circuitry was used in analog string machines to produce the ensemble effect. Quite often there'd be two or three different chorus circuits running at the same time. A simple tremolo pedal gives us the familiar volume pulsing effect, while Vibrato brings in pitch modulation in the same way that might be achieved using an LFO to modulator tone oscillator. A phaser pedal can add a vocal like whine to the sound, as well as adding movement. A flanger will produce a more hollow sounding sweep. At more extreme settings, you could use it as a kind of polite alternative to oscillator sync. But to get the most out of a flanger, you need to feed it with a harmonically rich sound, as in this next example, where I'll be patching an overdrive pedal before the flanger. Leaving the overdrive pedal turned on for the moment, I'm going to switch out the flanger pedal for a modulated resonant filter. This produces the familiar resonant sweep, but this time it's controlled via an LFO rather than following an envelope generator. OK, so that riff won't win any prizes, but it serves to illustrate the principle. Next we have a pedal where the input is controlling the envelope. This is an envelope filter pedal and it gives us the familiar sort of Wawa quacky duck sound that you get from a, a typical resonant filter in a synth. Again, you could try feeding the filter from a distortion pedal to get a more dramatic result. If you have a wha or pedal, it can be used to provide an alternative filter sound and whatever, which you've got full control. You can also park the wah wah pedal in one position to create a static filter effect. But now we get to one of my favourite transformative effects, which is granular delay. Granular delays break the sound down into short segments, which can be repeated and processed in different ways, often by shifting some of the segments or grains up or down by an octave or some other musical interval. Sometimes the grains can be reversed, and there are usually controls for changing the length of the grains, so you can go from smooth, shimmery soundscapes to quite jittery, broken, glitchy kind of sounds. The result is a complex texture that adds a lot of interest to otherwise bland sounds. Here's a setting that's rather more glitchy. Should you want to achieve something more radical you could try a ring modulator, where some of the elaborate pedals have control jacks that allow a full integration with a modular synth system. Ring modulators essentially take two inputs, termed the carrier and the modulator and then they generate sum and difference frequencies, but without any of the original sound being present. For that reason, some of the commercial ring modulator pedals have a mix control, so that you can bring back in some of the dry sound. If you have two sets of oscillator modules, you could try using one of those to feed the carrier input, and the other the modulator input of a ring modulator, as this can produce more predictable musical results, albeit with a lot of complex overtones. And of course you can always combine ring modulation with something else. Here it is feeding into a shimmer reverb. You can have a lot of creative fun by combining multiple pedals. Though there are some very practical reasons for putting certain pedals before others, for example you wouldn't normally put a pitch shifter after a reverb or delay because it would confuse it, it's still worth experimenting to see what happens if you break a few of those rules. Hmm, I'm not sure it'd have a lot of use for that one. If you want something less aggressive, how about combining an envelope filter with shimmer reverb? Sticking with good old shimmer reverb, how about we combine that with the granular delay that we used earlier? And here's another combination of reverb and granular delay. That's just a small taste of what pedal effects can do for you. If you use a lot of pedals then buying a decent pedal power supply system with multiple isolated outputs is a good idea, as it will help to keep the noise down and make sure that your pedals are performing at their best. The key is to experiment with whatever pedals you have or can borrow, and don't forget to look out for second hand bargains too. Before we finish then, let's look at a few more combinations of pedals and see what we can get out of our boring sawtooth synthesiser. Here's distortion coming at the end of the chain after a granular delay and some modulation. I've also switched on the arpeggiator. Well, putting the distortion at the end certainly makes it pretty nasty, but I'm sure somebody will have a good use for it. So for something a little more gentle, I've put the envelope filter at the beginning of the chain. That's followed by the cloud burst, which in turn is followed by a granular delay. Then at the output I found a nice modulated wobbly vintage sounding reverb. And just to remind you of the original synth sound. Well that's all for now but thanks for listening and please check out soundonsound.com for other podcasts and lots of other useful information on synthesisers, recording and all aspects of technology involved with music production. Thank-you for listening and be sure to check out the show notes page for this episode where you'll find further information, along with web links and details of all the other episodes. And just before you go, let me point you to the soundonsound.com/podcast website page where you can explore what's playing on our other channels.