Why Sine Wave?

In this post we will understand what it means to say “this song has a lot of high frequencies”, then hunt and capture the waveform that allows us to say this! Some Python code will be used, but understanding it is not necessary. Footnotes are more technically advanced.

The x coordinate of the circle… is frequency?!

A simple sine wave
A sine wave

Sine waves are widely agreed to be the “most basic wave” when doing anything involving periodic signals – whether radio circuit analysis or music synthesis. Indeed, the sine wave is pretty simple as far as waves go, and quite smooth to boot, but I’ve always asked myself: why the sine? There are many other simple, basic waves that could be used as a basis for a theory of frequencies.

A square wave, a triangle wave, a sine wave and a sine wave
A square wave, a triangle wave, a sine wave and a sine wave “fattened” by taking its square root

… and yet mathematicians and engineers, even musicians, always choose the sine[1]. What makes the sine so special? Could a theory of frequency analysis be built around a different waveform, and how different would it be? How different would music sound if we used another simple waveform as our basis? Continue reading

Business Model Exercise #1: geekar

I started exercising my idea muscles a few days ago.

Every day I think of 10 startup ideas and develop one into a business model. Some will be published here.

Lets begin with the first example – geekar, an Augmented Reality-enhanced retail, in the most early-adopter industry I know: geeks. geekar will sell comic books, tabletop roleplaying sourcebooks, board games, trading card games, manga, anime, computer games and so on.

Continue reading

Bootstrapping or Funding?

Another interesting question on the forums:


Is it really necessary to invest a lot of money to build something? I guess it depends a lot on the product. My start-up is based on a web app, and I don’t need to hire anybody at all, I do it all by myself, so I think I will only need to spend money on Google App Engine resources, which is not very expensive. I am being too optimistic? What do you think?


My Response

Hi Carles,

In your specific case as you tell it, it indeed sounds like bootstrapping is the way to go. But we have almost no information.

Just ask yourself these questions, for each atlernative (bootstrapping, getting angel-size investment, getting bigger angel-size investment and hiring help, getting VC-size investment):

What are my chances of success?

  • How much profit will the company generate*?
  • How much profit will I earn?
  • How will my lifestyle be before I become very profitable?
  • How much fun will it be?

* It’s not trivial that this has different answers for different initial investments, but if you think about it you’ll probably agree.

Make a table, think of the answers. They are different for every business and every founder. Who knows, you might even decide to get an investment and hire someone just because you feel lonely working alone, even though you can withstand spartan living conditions and have a slight preference for 100% of profit to 50%.

Illustration in Teaching

Watching Steve’s lectures, I just have to say this.

Illustration is amazingly useful when teaching / explaining / presenting / convincing.

I’ve held a firm belief that I cannot to learn to illustrate because I don’t think visually. I am realizing I’ll have to overcome it soon. It’s just too good a skill to pass over.

Here are some amazing examples of illustration skill tremendously improving teaching or presentation. I strongly recommend clicking all links:

Why’s (Poignant) Guide to Ruby by code poet “Why the lucky stiff”

Sketchnotes by graphic designer Mark Rohd.

“Bugs and Battleships” by Edward Z. Yang

“Starting Forth” by programmer/author Leo Brodie

Steve Blank (expected, wasn’t it?)

I believe all images are fair-use, authors that want an image removed – please contact me.


An interesting question on the forums:

While going through Lectures 1 and 2 I was hoping some sort of time frame was mentioned. Traditionally you have a project plan stating a time frame to finish up say, the marketing plan?

Monique Bizzell

My Response

I used to work in a place that took schedules very religiously. I did researchy tasks there, the kind that may be done in an hour and may be done in a week, and you can never know.

No matter how many times my boss asked me rephrased versions of “how long will it take you to be done by tomorrow noon?”, the tasks were done when I succeeded, and never before.

That’s how it is.

Scheduling limited time for research threatens to force you into market with a bad idea that will fail, and for no particular gain.

I personally recommend never to commit to a schedule unless somebody else will be blocking on you — which should never happen before you know what your product will be.

As managers, we tend to feel that if there’s no schedule we’re not in control – that’s a harmless irrational fear and should be dealt with like any other irrational fear.