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This section of the Scots Guide deals with Analogue Electronics with a special emphasis on Audio-related topics. There are also some specialist pages on the properties of cables as these relate to audio.

You may also download an Adobe PDF version [662KB] of the first eight lectures.

These days it is common for audio fans to spend time and money on purchasing ‘high performance’ cables. This area seems to have become immersed in mystery. The purpose of the pages linked below is to provide an analysis of what is often called ‘Skin Effect’ and assess its possible effect (if any) upon audio signals. The choice of materials, etc, is considered. Although the analysis is complex, the results are fairly straightforwards. If you are not familiar with the properties of transmission lines you may find it useful to look at parts 6 and 7 above before reading the pages linked below.

The following five pages deal with the use of “Twin Feeder” used to connect a power amplifier to a loudspeaker.

The page linked below provides a Java Applet that you can use to explore the effects of cable diameter, etc, upon the frequency response (in both power and time delay terms) of a twin feeder when used to link a power amplifier to a loudspeaker.

The following three pages deal with the use of coaxial cables as audio interconnects.

Domestic audio systems use connecting and loudspeaker cables that are usually far shorter than the wavelengths of EM signals at audio frequencies. This means that it should be possible to approximate the effects of such cables by using a simple lumped AC circuit theory approach. However, is this method really accurate for such cases, or should we use transmission line theory to ensure accurate results? The following page compares the two methods to reach a conclusion... More items will be added in due course, investigating other effects.

The analysis is based upon standard texts and seeks to avoid the simplifications that some authors have employed which sometimes lead to misleading results. The analysis is based upon the model of internal impedance given by Ramo, Whinnery, and van Duzer in their textbook, “Fields and Waves in Communications Electronics.” The computed results use the formulae given in Abramowitz and Stegun in their “Pocketbook of Mathematical Functions.”

“Bi-wiring” is a technique that some people advocate for connecting an audio power amplifier to loudspeakers. The belief is that this can lead to an improvement of the quality of the resulting reproduced sound. The following links are to some pages that explain what bi-wiring is, and try to assess if it can actually have any effect.

The link below is to a specialist paper on cables that may be of particular interest to Hi-Fi fans tempted to spend large amounts on expensive cables. This paper analyses some measurements published in a UK Hi-Fi magazine that claimed to have discovered a novel distortion mechanism in Audio cables.

The high-frequency units (tweeters) in loudspeakers sometimes fail, and this is associated with high power levels. As a result, there is a debate regarding the detailed reasons for this problem. The following pages consider various possible mechanisms.

Click on the button below to go to the main ‘Scots Guide’ page

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Content and pages maintained by: Jim Lesurf (jcgl@st-and.ac.uk)
using HTMLEdit, TechWriter, and Compo, on a RISCOS machine.
University of St. Andrews, St Andrews, Fife KY16 9SS, Scotland.