|
Audio Streaming InformationA Technical Introduction to Audio Cables
by:
Adam Blake
A Technical Introduction to Audio Cables
What is so important just about cables anyway?
One of the most common questions asked by consumers janus-faced with buying cables for their audio or house theater system is, “What is so important just about cables anyway?” They can cost as more or more than several of the hardware in the system and to many an it is difficult to understand why wire isn’t just wire.
To begin to understand how audio cables work, we have to start with the two essentially several types of audio cables you are likely to have in your system. The 1st type of cable is called an interconnect, which is used to connect various components together (such as a CD player to a receiver). The second type of cable is called the loudspeaker cable (this is the wire going from the receiver or electronic instrumentality to the speakers). It is important to realize that several types of cables are carrying the same information, just with several amounts of energy.
Interconnects carry a signal with really little energy. These cables only need just enough energy to convey the information from the source, for example a CD player, to the amplifier. The low energy requirement means that the signal in interconnects has really little current (usually in the range of thousandths of an amp).
Loudspeaker cables on the else hand, carry a large figure of energy. All of the energy required to come the speaker cones and do sound must come through the loudspeaker system cables. Because of the high-energy requirement in these cables the current is comparatively
high (currents can reach 10 amps or more).
The really basic reason why audio cables are important is because they change the signal going through them. There are two different, fundamental route that an audio cable can change the signal. The cable itself can change the signal, or the cable can allow outside sources of energy to change the signal.
In order to understand how these two situations can occur, some basic background electrical psychological feature
is needed.
Signals in all types of wires are sent
by the combination of voltage and current. Every signal has several amount of voltage and several figure of current. The larger the difference in voltage between two places, say the beginning and the end of a cable, the larger the figure of current, and vice-versa. The direct analogy to voltage and current is the flow of water through a hose. The figure of water flowing through the hose is correspondent to current. The water pressure in the hose is correspondent to voltage. The higher the amount of water pressure, the more water wish flow through the hose. The higher the figure of voltage, the more current will flow through the wire.
Every cable has a set of electrical properties that can be measured victimisation standard electrical testing equipment. The three most basic properties are resistance, capacitance and inductance. Spell a elaborated
description of these three different electrical properties is outside the scope of this article, a basic description of the relevant effects of these three properties can be given.
- Resistance opposes current. The higher the resistance the greater the figure of energy that is removed from the current and turned into heat.
- Capacitance opposes changes in voltage. If a voltage is increasing, capacitance wish cause the voltage to increase more slowly. If a voltage is decreasing, capacitance wish cause the voltage to decrease more slowly.
- Inductance opposes changes in current. If current is increasing, inductance wish cause the current to increase more slowly. If current is decreasing, inductance wish cause the current to decrease more slowly.
The final piece of background psychological feature
that is required for this article is what the audio signal looks like. If one were to take the speaker cover off a speaker to look at the speaker cone spell music is playing, you would-be see that it is moving back and forth. In order to come the speaker cone back and forth, the electrical signal must push and then pull the cone in rapid and continuation
fashion. This is accomplished by having an Cyclical
Current, or AC. Alternating Current just means that the voltage oscillates between positive and negative. Because the voltage drives the current, this means that the current likewise goes positive and negative. In else words, the current is going back and forth in the wire, just like the speaker cone. The subtle variations in how fast the voltage and current go back and forth creates the several sounds that we hear once
listening to music.
How a cable itself affects the audio signal
Now, going back to the route that the cable itself can change the signal going through it, let’s consider several types of cables separately.
As expressed
previously, interconnect cables carry a really small amount of current. Relative to the current the voltage is large. Because of that fact, capacitance is important, but inductance is comparatively
unimportant. As the voltage oscillates between being positive and negative, the capacitance slows the voltage changes down, and causes delays. This can cause perceptible distortion in the sound. Because interconnects have really little current, resistance is not more of a factor. Even as an interconnect with extremely high resistance wish only move out an infinitesimally small amount of energy.
The signal in loudspeaker system cables is essentially the opposite of the signal in interconnects. Several cables have the same information, but in loudspeaker system cables, the voltage is small and the current is large, comparatively
speaking. Because of the high current, several resistance and inductance are important in loudspeaker system cables. The higher the resistance, the greater the figure of energy that wish be absorbed by the cables. The resistance wish not cause any distortion, but it wish decrease the volume of the sound. The inductance on the else hand, can cause distortion. As the current oscillates between being positive and negative, the inductance slows the current changes down, and causes delays.
How a cable lets outside sources of energy affect the signal
As expressed
previously, the second fundamental way of sterilisation a signal passing through an audio cable is to introduce outside sources of energy. This outside energy is typically termed “noise”. By definition, if any energy is absorbed by the signal, the signal has been distorted.
There are many an potential sources of noise about audio cables. Several of the more common sources of noise, such as radio frequency waves, are familiar to most people. Once
wiring up a radio, oft-times a user
must attach an antenna. Antennae are by choice designed to channel radio frequency energy into a stereo. Simply like an antenna, it is entirely possible for an audio cable to pick up radio frequency energy. If you are not intending to listen to the radio, this is not a welcome effect. Electronic components, electrical cords, sound waves, and even the sun, are all capable of creating noise. Electrical cords create magnetic force
fields about them that can transfer energy to a cable. Sound waves create mechanical vibrations that can be changed
into electrical energy that is adscititious to an audio signal. Because there are so many an different types of noise, there are many an methods used to prevent a cable from picking up noise. Shielding, twisting of conductors, and mechanical damping are all common noise protection methods in cables.
While noise affects several interconnects and loudspeaker system cables, generally the effects are far more significant in interconnects. This is because the signals in the interconnects have far less energy. Since most forms of noise are inherently low energy to begin with, this means that it is far easier for them to modify the low energy interconnect signals than the high-energy loudspeaker system cable signals.
Macro vs. Micro
The parameters discussed so far have been primarily “macro” effects. These are for the most part the top-level parameters that effect cables. These parameters as well as others not discussed here likewise exist at a “micro” level. Taking capacitance as an example, a given cable wish have an overall capacitance that can be measured. This overall capacitance is a “macro” level parameter. The same cable can also be analyzed as 1000 separate but connected pieces. Each piece wish have a local capacitance. These local parameters are “micro” effects and can have their own impact on the signal separate from the “macro” effects.
The impact that the “micro” level parameters have on an audio signal is ordinarily less than the impact of the “macro” level parameters. However, they do still do a difference in the signal transfer. The various route that audio companies choose to either mitigate or ignore these “micro” level details is, in part, responsible for the immense array of different cable designs. From refrigerant
treatments and precious metal wires, to fine silk insulation and fluid filled cable jackets; extreme cable designs abound. Will I hear the difference?
The fact of the matter is that cables do alter the sound going through them, and that it is audible. You do not need to be an expert, or an audiophile, to hear the difference. To demonstrate this point, just listen to your stereo. If you close your eyes, does it sound like the music is being played live right in front of you? This is what audiophiles strive for, and unless you have a really high-fidelity system, your answer to this question wish most likely be no. You may have a hard time describing what exactly does not sound right just about your system, but you cognize that it doesn’t sound like a live performance.
Of course, the reason why the music does not sound live cannot be blessed exclusively on the cables. The degradation of the sound occurs in every component of your system. However, the point here is that even as a casual auditor can find the subtle distortions that can prevent music playback from sounding live. Up the quality of your audio cables will improve the sound quality of your system.
It is fairly safe to say that no matter what cable you use, the modifications to the sound wish be small. Audio cables will ne'er
cause a auditor to hear a piano once
a flute is being played. However, it is the small detail that does all the difference between nice and bad quality sound. That is why really strong opinions are formed just about various cables. As audio systems continue to improve in accuracy, listening to a “live” performance in your living room gets closer to reality. Cables are an sanctioning
factor for advancements in audio reproduction and can play a remarkably important role in your system.
Written by: Adam William blake
CEO / Co-Founder Pear Cable, Inc. www.pearcable.com For a more elaborated
explanation of cable design theory that Pear Cable thinks is relevant, see the “cable design” white paper accessible on pearcable.com
Simply just about the author:
Adam William blake
is the CEO and Co-Founder of Pear Cable, Inc., a manufacturer of high-fidelity audio cables. http://www.pearcable.com
| |