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Step 2What is Distortion?
If you know what distortion is, skip this step.
So, now that you know what distortion sounds like, what is it?
Distortion is the clipping of sound waves, or AC at whatever frequency the note you are playing is.
The term "clipping" refers to the tips of each wave "clipped" off. There are several ways to go about doing this, but I went with the good ol' diode clipping method.
A diode looks like a resistor, but is not very similar. It lets a certain amount of voltage (called forward voltage drop) go past it, while the rest is sent to ground. For example, if you had a hose, imagine a valve that only lets 1 psi go by, while the rest is diverted to a different hose. Back to resistors; that resistor would have a forward voltage drop of 1. My design calls for a red LED, which has a forward voltage drop of ~2 and two 1n914 diodes with a forward voltage drop of ~.7 each (more like .65-.68). They are set up in such a way to let 1.2 -V and 2 +V through. That means if your signal was at 4 volts, you would be clipping 2.8 volts off of the -V and 2 off of the +V. That is without resistors and capacitors. See the simulated picture below for an example.
As you can see in the next picture, there is both soft and hard clipping. They will both distort the sound, but hard clipping is more metallic (think heavy metal music) while soft clipping sounds more like a tube amp turned up too high. They term soft and hard refer to the sharpness of the clipping. Soft is more curved, while hard has much more of an angle. See the image for a visual.
So, now that you know what distortion sounds like, what is it?
Distortion is the clipping of sound waves, or AC at whatever frequency the note you are playing is.
The term "clipping" refers to the tips of each wave "clipped" off. There are several ways to go about doing this, but I went with the good ol' diode clipping method.
A diode looks like a resistor, but is not very similar. It lets a certain amount of voltage (called forward voltage drop) go past it, while the rest is sent to ground. For example, if you had a hose, imagine a valve that only lets 1 psi go by, while the rest is diverted to a different hose. Back to resistors; that resistor would have a forward voltage drop of 1. My design calls for a red LED, which has a forward voltage drop of ~2 and two 1n914 diodes with a forward voltage drop of ~.7 each (more like .65-.68). They are set up in such a way to let 1.2 -V and 2 +V through. That means if your signal was at 4 volts, you would be clipping 2.8 volts off of the -V and 2 off of the +V. That is without resistors and capacitors. See the simulated picture below for an example.
As you can see in the next picture, there is both soft and hard clipping. They will both distort the sound, but hard clipping is more metallic (think heavy metal music) while soft clipping sounds more like a tube amp turned up too high. They term soft and hard refer to the sharpness of the clipping. Soft is more curved, while hard has much more of an angle. See the image for a visual.
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Mar 9, 2009. 11:48 AMpyrohaz
says:
Good use of falstad's circuit simulator I see there ;) WOO!
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11
Mar 14, 2009. 2:18 PMheyzuphowsitgoin (author)
says:
Why thank you!
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