The Power of Sine - an ER-301 Challenge

I thought we could do with a little bit of inspiration to get those brain cells working and explore the extraordinary possibilities of the humble sine wave in the context of the ER-301.

So, just for fun here’s an audio challenge; create a piece of music using ONLY sine waves in the ER-301.


  1. You can use any of the units in the ER-301 so long as they are not sound sources i.e. you can only use the Sine OSC as a sound source; you can’t use any of the other OSC units, no cheating using anything else that generates any sound and definitely no sampled audio (but see 2 below)!

  2. The Looper and Sample players are allowed but must only process audio created using the Sine OSC as sound source

  3. You can manipulate/modulate the Sine OSC using anything, even external modules, but the modulation source must be a sine!

  4. Envelopes are not allowed but you can use the Skewed Sine Env unit!

  5. The sounds you create may be processed by external effects, e.g. reverb, but if you modulate the reverb you must, yep you guessed it, only use a sine!

  6. No triggers - if you want to trigger something - use a sine!

  7. Catchall - you must not use anything else that could be construed as audio or modulation that isn’t a sine - use your common sense :wink:

That’s it… are you up to the challenge?

Lets see what you can do :smile_cat:


I was with you right up until “Envelopes are not allowed…” That’s just a bridge too Fourier.

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Heheh, have you tried the Skewed Sine Env?

I haven’t. But fer gods throw a life preserver to a Chowning man.

Nope… :smiley:

Whole point is to work through the possibilities and see just how far you can go just using a sine, if that concession was made you’d miss out on learning some great stuff :wink:

Sorry for going off on a tangent. …But you’re partially responsible. I’ll cancel the rest of my sideband commentary.

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Not at all, it’s a good question, no apologies necessary, but trust me - I know what I’m doing hehe :smiley:

I have actually tried it already and it’s ace, really makes you think differently, creates unusual effects and I’m reasonably confident it will improve your knowledge.

It’s all optional of course - it is just for fun :slight_smile:

Really like these kinds of exercises, great concept too! Will try and find time to contribute something!

Yeah me too :smile_cat:

The thing that struck me most about this one is that it’s the features on the ER-301 that, perhaps uniquely, make this challenge so possible and open ended.

To put it another way, if I look around the rest of my system it would be a lot harder to do without the ER-301, doable for sure, but it eliminates an awful lot of functionality. I might change my mind on this though.

Currently I am using 6 sine waves from around the rest of my system, 2 from Kermit and 4 from Batumi. I just counted and there’s at least another 10 to go at :smiley:

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Neat idea. Don’t have mine yet (getting close!) Additive synthesis comes to mind. How much CPU does a sin OSC take? :slight_smile:

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Very little I believe!! Haven’t checked though!!

Todays hint: Don’t forget FM synthesis :wink:

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I forget the exact number, but the other week I set out to build a kind of saw which had harmonic content that spanned the range of the piano, with slight level modulation on every mixer, using only sines and mixers, and it started getting hairy around the 5th partial

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Was literally thinking about this the other week. Can’t wait to make something!


Completely unscientific but based on other things I’ve seen the 301 doing, I’m surprised to hear around 5 was the magic number…

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The chain I set up organized everything in 8ves, so by the time I got to the mixer for partials 5/10/20 etc. there were around 38 active internal sines and mixers. I’m sure I had more in the chain that were bypassed, but do not recall specifically.


Ah, that explains it. Would not surprise me a bit if 38 was the magic number of sin units that started to bog it down, along with other stuff in the chain as well. :wink:

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Re-reading my first post on the matter, I see that I could’ve stated my experience more clearly! It will certainly take (way) more than 5 sine waves to begin to notice an affect on CPU performance. Stoked to see what people come up with as the thread progresses.

Anyone try this yet?

Here’s a couple of inspirations, @Joe’s excellent phase distortion example and the filter kick:

So are external sequencers/keyboard controllers allowed?

Hehe… do they output sines? :joy_cat:

OK, maybe this should be a relaxation of the rules, any objections?