CORDIAL KNOWLEDGE BASE

Capacitance

The core properties of an electrical line comprise so-called line coatings such as capacitance, resistance or inductance. But what are capacitance coatings and to what extent do they affect my music?

Capacitator plates are called, among other things, coatings. A cable has similar properties as a capacitor, because two parallel cable wires act together and affect each other like such a parallel connected capacitor. This phenomenon helps us describe and define capacitance coating. The capacitance coating defines the capacitance of the cable thus (Farad or picofarad per meter (F/m or pF/m)).

Due to the conductive properties, which are similar to those of a capacitor, signals are attenuated. The longer the cable, the greater the capacitance and the more treble amounts are filtered out of the signal.

Capacitance, though, can be influenced by several factors:  

  • the area (length of the cable and copper cross-section)
  • the distance between the insulated/shielded inner cable conductors
  • the nature and type of the shielding 
  • the frequency: high frequency (HF) cables are e.g. coaxial cables, typical low frequency (LF) cables are speaker cables, RCA (Cinch) cables or the typical instrument cables
  • the impedance (AC resistance)
  • etc.

So, what does the capacitance and the way it is influenced now de facto mean for musicians or event/sound engineers?

For example, a longer instrument cable in the first place "sounds" duller than a shorter version. In some cases, this can also be a desired effect (e.g. for electric bass sounds), but manufacturers of high-quality cables generally counteract attenuation effects due to a high capacitance, because a sound signal per se should be as "clear" as possible. And this is achieved by the adjustment of technical factors such as the copper cross-section used, the best possible composition and use of insulation materials or the type of shielding and employed materials in general.

The combination, coordination and technical set-up of the individual parameters make the topic "sound of cables" a really exciting subject for all sound freaks. So, the sound of one cable series may be perceived as "warmer", while other types have a certain "crispness". And, therefore, any musician or technician can find her or his own “personal” cable, depending on her or his taste and intended use. Think of a typical mastering situation: a recording engineer may probably demand the clearest possible signal for further processing, i.e. as little capacitance as possible. But maybe she/he is just aiming at a warmer/muddier sound and, consequently, resorting to a higher-capacitance cable. So, it’s quite obvious: this field offers you  virtually unlimited choices when it comes to generating your individual creative sounds.