I've seen mention of dynamics on the Internet generally associated with single coil pickups, and it seems that people assume that those have more dynamics.
However, there is an interesting forum topic in which someone argues about that with convincing arguments.
And there seems to be consensus on the fact that the word dynamics may be used with different meanings, that people tend to repeat stuff they read on the Internet which leads to unsubstantiated rumors...
Dynamic range definition
What I'm talking about is the way the pickup outputs low volume when I pick gently and huge volume when I slam hard. I've seen mentions of dynamic range and I think this is it. Is this correct?
For instance, my friend has this Telecaster with a single coil, and it is remarkable how much he can play softly them strum harder and get a huge volume difference (huge dynamic range). On the other hand, my SG is equipped with humbuckers and I don't get that much of a difference. Even strumming very hard, I don't get that volume increase (low dynamic range).
The enemy of dynamic range would be compression. Compression increases the volume on low level signals so that everything is loud.
Pickup and amp influence
We've been swapping amps for the sake of testing. His amp (Powerball, 100 W) is much louder than mine (Ironball, 20 W), and it seems the difference is attenuated but his guitar still wins with the dynamic range contest.
Those tests would indicate that the pickups do matter, but in this comment, user Gnobuddy says that pickup answer can be considered linear and lack of dynamic range is due to compression in the amp only.
Maybe a way to conciliate both theories is to say that high gain humbuckers tend to reach max volume earlier while single coils exploit the lower volume range. Basically what is developped here.
Does this mean I should get more dynamics by just lowering the gain on my amp?
In other words, would using lower gain pickups help just because I would get a lower gain, which I could achieve just the same by lowering the gain on the amp?
Right now, I play with master at 100% but a relatively low gain on the clean channel to avoid crushing on the arpeggios. I don't think I can lower the gain any more. I would like to get more expression by having some notes sound louder, for instance get a huge boom when strumming the lower string, and I'm thinking of getting a single coil or P90 neck pickup.