Clipping versus saturation

[burk48237]

Clipping is the effect on the sine wave. This means the tops of the sine waves are clipped off. With solid state, it clips them evenly. With tubes, it compresses the peaks until they are flat, rather than cutting them off. That is why they sound different.

Saturation is what happens to the component, whether be it a transistor or a tube, when an increase in input current fails to produce an increase in current at its output.

Clipping and saturation are two very different things, technically.

Very true, Also SS amps clip with even harmonics, this is rather displeasing to the ears much as playing a root, second, four, and six is over a major chord. Tube saturation produces odd harmonics. I think most would find thats much more ear pleasing.

Also 300W is not a lot of power with a loud rock band. You may be able to help the situation with EQ. Cut the low end and boost the low mids. It may not sound great soloed, but it will blend with the bass drum better and low mids don't require as much power to produce as the thumping ultra lows. If your guitar players playing with a real bass heavy sound and a marshall stack, your going to need 500 watts minimum into 4 ohms to keep up with him.

 

[bongomania]

Clipping is the effect on the sine wave. This means the tops of the sine waves are clipped off. With solid state, it clips them evenly. With tubes, it compresses the peaks until they are flat, rather than cutting them off. That is why they sound different.

Saturation is what happens to the component, whether be it a transistor or a tube, when an increase in input current fails to produce an increase in current at its output.

Clipping and saturation are two very different things, technically.

This is a good point, but also an illustration of one word being used differently in different contexts. People using "saturation" to mean preamp tube driving are talking about voltage handling in the audio path, not current handling elsewhere.

 

[seamonkey]

Checkout Blackstone's site for explanations on the even/odd confusion There's an applet that lets you play with the harmonics.
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Most people don't hear clipping.
But read Rane's paper for what causes things to sound bad at Extreme clipping.
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It's the same thing that blows tweeters.

OP - how about posting a clip of what your amp sounds like? From your description it sounds like something is not normal.

 

[Hookus]

This is a good point, but also an illustration of one word being used differently in different contexts. People using "saturation" to mean preamp tube driving are talking about voltage handling in the audio path, not current handling elsewhere.

I realize that, and that is exactly what I am talking about as well. Higher plate voltage means higher current flow through the tube. Assuming resistance stays the same, an increase in voltage nets a proportionally equal increase in current.

There is no context issue, it is a slang issue. Clipping happens to a sine (or other) wave, and saturation happens to components. Generally, clipping is caused by saturation, in both tube or SS. How the wave clips is what makes them sound different, but they are both caused by saturating (or nearly in the case of tubes), any amplifier stage in the signal path. That means it may be a pre or power stage.

 

[Bob Lee (QSC)]

Very true, Also SS amps clip with even harmonics, this is rather displeasing to the ears much as playing a root, second, four, and six is over a major chord. Tube saturation produces odd harmonics. I think most would find thats much more ear pleasing.

Actually, clipping in a SS amp, being symmetical about the zero-volt axis, produces odd-order harmonics that may tend to be harsh-sounding, especially in the higher orders. (A tube amp can also clip symmetrically, but because the distortion tends to be more of a "squashing" than an abrupt flat-topping, the harmonic energy generated tend to be almost entirely low-order and less likely to be harsh.) If the tube amp clips asymmetrically, it will tend to produce both even and odd harmonics. Even-order harmonics in reasonable amounts may tend to be consonant with the original signal and therefore may add some euphonious quality to the tone.

 

[Bob Lee (QSC)]

Clipping can and does happen to sinusoidal and non-sinusoidal waveforms alike.

I always think of saturation as more of a magnetic phenomenon, like a tape saturation or a transformer core saturating, while clipping is a waveform voltage phenomenon.

 

[greenboy]

I always think of saturation as more of a magnetic phenomenon, like a tape saturation or a transformer core saturating, while clipping is a waveform voltage phenomenon.

Me too, from years of projects that benefited from running levels hot onto tape.