Technology of the Guitar by Richard Mark French

Author:Richard Mark French
Language: eng
Format: epub, pdf
Publisher: Springer US, Boston, MA

The output voltage of the voltage divider circuit is

(4.1)

The amplifier can only work on the voltage it sees, so our goal is to make the output voltage as large as possible. In electrical terms, we want to drop as much voltage across the load as we can. The obvious way to do this is to make RL large compared with RP. Similarly, we want output impedance of a component to be small compared to the input impedance of the component it is feeding. A good guideline is Zin ≥ 10 Zout. Thus, it is not surprising that the output impedance of pickups is generally in the range of 5 kΩ - 15 kΩ while the input impedance of amplifiers is generally in the range of 100 kΩ - 1MΩ. Let’s start by looking at pickups.

In spite of the extremely simple design of inductive pickups, there are a number of design features that can be changed to affect the resulting sound. For example, the number of turns in the coils can be changed along with the diameter of the wire. Additionally, the strength of the magnetic field can be altered by changing the geometry of the magnet or the material from which it is made. The number and position of the pole pieces can be varied. Indeed, some pickups replace individual pole pieces with a single blade (often called a rail) spanning the width of the strings. Figure 4.17 shows a humbucker pickup with rails replacing the individual poles. While this is a humbucker and has two coils so that it is not sensitive to electromagnetic noise, it is single coil sized and can be used in place of a single coil pickup.

Fig. 4.17A Single Coil Sized Humbucker with Rails Rather than Individual Pole Pieces (Image courtesy of Seymour Duncan, http://www.seymourduncan.com)

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.