Why do humbucker guitar pickups sound different from single coil pickups? - Page 1
Forum section: electronics / projects

author: e100
author_rank: Frequent Contributor
timestamp: April 25, 2017, 07:29:31 am
content: Is it mainly due to the increased inductance of two coils in series, or is it the physical separation of the two sensing elements (due to the thickness of the two coil windings) so they aren't sensing the exact same bit of string?If it's an inductance issue, would summing them electronically instead of having them in series fix that problem?

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: April 25, 2017, 07:52:14 am
content: You may find some answers in thisarticle on electrical characteristics of guitar pickups.But I bet, there will be some experts on that matter on this forum

author: Stuart Coyle
author_rank: Contributor
timestamp: April 26, 2017, 06:02:44 am
content: Phase cancellation is why. The two coils mean that induced noise gets cancelled out.The coils are set up with the polarity pointing in opposite directions, thus induced noise from things like horribleold transformers in 1970's guitar amps is cancelled out.

author: e100
author_rank: Frequent Contributor
timestamp: April 26, 2017, 07:11:31 am
content: Quote from: Stuart Coyle on April 26, 2017, 06:02:44 amI understand the mains frequency interference cancelling, but what causes the difference in frequency response in the musical region above 80 Hz compared to a single coil.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: April 26, 2017, 07:45:09 am
content: Good read!

author: e100
author_rank: Frequent Contributor
timestamp: April 26, 2017, 09:09:51 am
content: Quote from: frozenfrogz on April 26, 2017, 07:45:09 amSome of the terminology doesn't make much sense to me.It refers to presumably what are two different models of humbucker, HMB-01 and HMB-02 which appear to have different wiring colour schemes. I don't know if these are generic or if the author is talking about two specific models, or if the wiring he is using is non-standard just to illustrate a point, or whether this is how they would be wired in practice.On pages 4/5 it says that raising the load resistance would raise the high end frequency response. Is this what active pickups with op-amps effectively do?Presumably too high of an impedance would result in more capacitive interference?

author: Buriedcode
author_rank: Super Contributor
timestamp: April 26, 2017, 02:27:15 pm
content: Quote from: e100 on April 26, 2017, 09:09:51 amFrom what I understand, active pickups serve two purposes. Firstly, to create a 'hotter' signal - that is a larger output signal making it much easier to overdrive the front end of amps. This also means there's a higher SNR. You can turn the gain of the amp down to achieve the same volume, but because the gain is lower, noise is amplified less.Secondly, the on-board preamp has a high input impedance, and a low output impedance (again, for driving long cables). This means the low-pass filter effect of a long guitar cable is much smaller. Also I think the volume knob on the guitar doesn't roll off the highs as it does in passive setups.I could be wrong! I have never used active pickups, often they use 9V PP3's which I hate with a passion. Just seems like more hassle. With that said, I built my own preamp for my acoustic pickup as they have such a massive output impedance, you really need one.