Post by antigua on Sept 9, 2017 16:20:38 GMT -5
One thing that can be seen with increased magnetic pull on the strings is a more rapid variation in amplitude on the positive and negative side of the cycle. Magnet pull is increased when the pickups have stronger magnets, or the pickups are set closer to the string, or when you play frets higher up the neck, causing the string to come closer to the pickup.
This graphic below shows a wave form of a Tonerider AlNiCo IV neck humbucker in a Les Paul, being plucked and sustaining for 15 seconds, with the pickup being moved closer to the string with each pluck. You can see that the amplitude becomes more "wobbly" as the pickup comes close to the string:
Despite the asymmetry, the overall amplitude is fairly consistent, so you generally don't hear the volume change too much as the string rings out. But that is not the case if you are using gain, and that gain features asymmetrical clipping. Asymmetrical clipping means that either the top of the bottom side of the wave form is producing harmonics form distortion, but not both, or at least not to the same degree. The net result is that, while the pickup distance might not cause the clean sound to change all that much, it might cause the distorted sound to change a lot, if the distortion is asymmetrical.
Here is an example of distortion that is symmetrical versus asymmetrical. The same pluck is presented three times; clean, symmetrically distorted, and asymmetrically distorted:
www.echoesofmars.com/misc/clipping.wav
If you look at the asymmetrical distorted waveform (right side), compared to the symmetrically distorted waveform in the middle, they look much the same on the positive side, but the negative side of the asymmetrical wave form looks just like the negative side of the clean wave form (left).
Another interesting aspect of the clipping, in general, that can be seen the spectral analysis, especially if you look at the lower harmonics near the bottom, the clipped sampled (center and right) show induced modulations in the amplitude that are not seen, at least not easily, in the clean waveform (left). The harmonic lines show "breaks" where the volume for that particular harmonic drops off briefly. Notice that the asymmetrical clipping (right) causes wider an more dramatic modulations of the fundamental, first, and second harmonics in particular.
In summary, stronger magnetic pull between the pickup and string might not sound much different when playing clean, or through a signal chain with symmetrical clipping, but when there is asymmetrical clipping present, it can bring out a modulation in volume that would otherwise be undetectable with our ears.
This graphic below shows a wave form of a Tonerider AlNiCo IV neck humbucker in a Les Paul, being plucked and sustaining for 15 seconds, with the pickup being moved closer to the string with each pluck. You can see that the amplitude becomes more "wobbly" as the pickup comes close to the string:
Despite the asymmetry, the overall amplitude is fairly consistent, so you generally don't hear the volume change too much as the string rings out. But that is not the case if you are using gain, and that gain features asymmetrical clipping. Asymmetrical clipping means that either the top of the bottom side of the wave form is producing harmonics form distortion, but not both, or at least not to the same degree. The net result is that, while the pickup distance might not cause the clean sound to change all that much, it might cause the distorted sound to change a lot, if the distortion is asymmetrical.
Here is an example of distortion that is symmetrical versus asymmetrical. The same pluck is presented three times; clean, symmetrically distorted, and asymmetrically distorted:
www.echoesofmars.com/misc/clipping.wav
If you look at the asymmetrical distorted waveform (right side), compared to the symmetrically distorted waveform in the middle, they look much the same on the positive side, but the negative side of the asymmetrical wave form looks just like the negative side of the clean wave form (left).
Another interesting aspect of the clipping, in general, that can be seen the spectral analysis, especially if you look at the lower harmonics near the bottom, the clipped sampled (center and right) show induced modulations in the amplitude that are not seen, at least not easily, in the clean waveform (left). The harmonic lines show "breaks" where the volume for that particular harmonic drops off briefly. Notice that the asymmetrical clipping (right) causes wider an more dramatic modulations of the fundamental, first, and second harmonics in particular.
In summary, stronger magnetic pull between the pickup and string might not sound much different when playing clean, or through a signal chain with symmetrical clipping, but when there is asymmetrical clipping present, it can bring out a modulation in volume that would otherwise be undetectable with our ears.