Methods Of Getting Distortion

[zanshin777]

I saw somewhere these methods of getting distortion. I don't know some of them. Can you explain those methods which i don't know?

1 Pre Distortion Equalization : ?
2 Preamp Tube Distortion : Adjusting the signal coming to Preamp by dialing the Gain Knob
3 Post-Distortion EQ : ?
4 Power Tube Distortion : Dialing the Master Volume Knob to get beyond Clipping Point of the Power Amp Tubes.
5 Tube Rectifier Compression : ?
6 Output Transformer Distortion : ?
7 Guitar Speaker Distortion : Getting Distortion by using excessive Input or Volume beyond Transient Response of the Speaker.
8 Guitar Speaker And Cabinet Frequency Response : ?

 

[uOpt]

Re: Methods Of Getting Distortion

Well you have to treat linear and nonlinear distortion separately. Linear distortion is EQ or frequency response, that means simply changing how loud various overtones are relative to each other. Non-linear distortion is adding overtones, usually simply by clipping some amplification stage.

You always combine the two. Clipping only sounds good if you cut off frequencies over a certain limit, that's why you always have a tweeterless guitar cabinet or a speaker simulator and never a full-range output.

EQ is much more effective after the clipping but you can also shape how the clipping reacts by EQing before the clipping stage. In particular, taking bass out can make the clipping more responsive.

There is also one that you didn't mention and that is the non-linear distortion that you get out of having your pickup very close to the string. It's not magnet pull, it is simply that if the string executes a perfectly good sine curve for one overtone it doesn't arrive as a sine after the pickup. Since the magnetic field is stronger the closer you get the "low swing" of the string induces a stronger signal than the "high swing". So each individual sine wave is turned into a more complex wave, and that means new overtones, which is the definition of non-linear distortion.

 

[Jeff5]

Re: Methods Of Getting Distortion

Almost always number 2. I'm not quite sure what some of the others are! Sometimes I'll add a boost in front or will add an OD pedal to my clean channel for some slight gain.

 

[jeremy]

Re: Methods Of Getting Distortion

ive been using a 12w amp with a greenback and running the volume high enough that that it breaks up. its hard to say where the distortion comes from. preamp, power amp, output tranny saturation, speaker break up... true is its probably a magic combo of all that

 

[tonello]

Re: Methods Of Getting Distortion

Can't say I know most of them. I understand preamp and poweramp distortion, but when most of mine comes from a box, I don't need to understand the rest.

 

[zanshin777]

Re: Methods Of Getting Distortion

Well you have to treat linear and nonlinear distortion separately. Linear distortion is EQ or frequency response, that means simply changing how loud various overtones are relative to each other. Non-linear distortion is adding overtones, usually simply by clipping some amplification stage.

You always combine the two. Clipping only sounds good if you cut off frequencies over a certain limit, that's why you always have a tweeterless guitar cabinet or a speaker simulator and never a full-range output.

EQ is much more effective after the clipping but you can also shape how the clipping reacts by EQing before the clipping stage. In particular, taking bass out can make the clipping more responsive.

There is also one that you didn't mention and that is the non-linear distortion that you get out of having your pickup very close to the string. It's not magnet pull, it is simply that if the string executes a perfectly good sine curve for one overtone it doesn't arrive as a sine after the pickup. Since the magnetic field is stronger the closer you get the "low swing" of the string induces a stronger signal than the "high swing". So each individual sine wave is turned into a more complex wave, and that means new overtones, which is the definition of non-linear distortion.

1 - Frequency Response means that the Frequency Range of an amp or a speaker reproduce. So I don't know Linear Distortion.
2 - The tone we get after passing the clipping point of an amp is non-linear distortion? And in this way do we add new overtones to the tone?
3 - You say that by reducing the bass amount of the tone is easier to get clipping point? Is it Post-Distortion E.Q. or Pre-Distortion Equalization?

 

[uOpt]

Re: Methods Of Getting Distortion

The way I learned the terminology "linear distortion" is distortion that does not add it's own overtones (aka EQ) and "nonlinear distortion" is adding overtones (clipping).

You can change how a clipping stage reacts to playing by putting a EQ pedal in front of it. It is confusing since you don't get any frequency response change corresponding to the EQ settings out of doing this. But the things that cause more or less clipping change and that makes the clip react differently to playing.

Most classic tube amps for distortion have a pre-clipping EQ. That's why the EQ is so "useless". It isn't changing the EQ, so to speak, but it is very important.