|
CABLE-ABC
|
|
|
The devices and speakers do not, of course, float freely in the air.
The conditions of the support surfaces and the type of acoustic coupling are very important and influence the sound quality strongly. Acoustic coupling is the transmission of vibrations between the support surfaces and speakers / devices, or between the devices. The choice of Pics and absorbers enables the acoustic coupling or uncoupling of the speakers / devices. Pics perform a sort of acoustic coupling. Concentrating the weight on four tiny points creates such high pressure that the vibrations are transmitted very well. Speakers / device form one acoustic unit. For speakers that is often an advantage as they are more stable and can steer the individual chassis more precisely with the help of the virtual higher weight. This only works on very stable ground (concrete). For wooden floors, absorbers are usually recommended. Absorbers uncouple devices and speakers from the support surfaces. Special materials absorb vibrations so that the devices and speakers seem to float as far as acoustics are concerned. This is recommended for strongly resonating surfaces that swing easily (such as simple hi-fi and video racks, shelves, wooden floors etc.). In rental flats this can also be an advantage as the neighbours are not disturbed, especially if the home cinema contains a powerful subwoofer. Not only speakers need suitable feet. The electronics also need to be set up properly. This is because vibrating components on the boards can change their attributes / values. This may change the adjustments of the complete circuit. Experience has shown that picture quality of video components increases as well as sound quality if the set-up is done right. |
|
|
Cables are passive elements with a filter effect defined by construction, surrounding and physics. This means that they create some losses and changes of the signals to be transmitted.
High end cables are intricately and carefully constructed and manufactured to minimise these losses and changes. However, passive cables, so cables without electronics, have natural physical limits. In active cables, the physical limitations are extended by the use of electronics. The electronics have to be developed to affect definite cable parameters. For example, the special electronics in our active speaker cable LS-A1 neutralise the inductivity of the cable. Experience tells us that inductivity in speaker cables is the main cause for sound distortion. The active RCA-Audio cables NF-A1 possess electronics that adapt the inputs and outputs of the devices to the impedance of the attached cable. A tube stage adds additional “sound optimisation”. In addition, the electronic has a powerful output stage that works even over very long cable distances. |
|
|
Sometimes similar signals are transmitted through different plug connections. Often it is simply a mechanical difference between the plugs and sockets while the actual signal remains identical. For example, an S-video connection is usually made using a Hosiden (Mini-DIN) plug. Many devices also conduct the S-video signal through a Scart socket. An adapter is necessary to connect a device with a Hoside S-video output to a device with a Scart input.
The adapters described above are passive types, which carry out a mechanical adaptation without changing the signal. Active adapters will, in case of signal incompatibility, change a signal so that a proper connection is possible. One example are the Opto <-> Coax transformers. They transform an electrical signal into an optical light signal and vice versa |
|
|
Instead of one, approx. 1 mm thick fibre, the optical conductor in AMD technology consists of 280 separate glass fibres, each about 50 um (50 thousandth m) diameter (AMD = Anti Mode Dispersion). These separate conductors are so thin that they transmit only direct beams of light (Mode) and suppress unwanted reflections. The runtimes of individual modes are therefore identical and 100 % of light energy reaches the receiver simultaneously. This means that the impulse duration at input and output is identical. There is no jitter effect. This is essential for “stress free” data recognition. The D/A converter can work without constant error correction.
|
|
|
This coaxial cables are tuned to forward very high frequencies. They need to have a cable impedance of 75 Ohm. Differences in quality are basically the screening/shielding ratio and the signal damping ratio (loss).
|
|
|
This is the general name for audio cables connecting, for example, CD players and amplifiers. They are also called RCA-Cinch cables or NF cables.
These cables transmit the analogue music signal separately for each channel. As the music signal is very weak and sensitive at this part of the hi-fi system, the cable needs to be of special construction. Good screening is especially important here. This is why audio cables are co-axially constructed, so from one signal conductor and a screening which is also used as a return lead. Symmetrical or double symmetrical constructions guarantee an even better transmission. |
|
|
Car hi-fi amplifiers are connected to the battery through battery and ground cables. The cross-section of the cable must be adapted to the power consumption of the amplifier. An oversized cable provides additional performance and dynamics. There is little danger of a cable being “too thick”.IMPORTANT: The battery cable (+) must be protected through a suitable fuse directly at the battery! Please also refer to our Car Hi-fi Guide.
|
|
|
Depending on the connection terminal loudspeakers can be connected in various ways. There are the following variations:
SingleWire This is the standard way to connect a speaker. The speaker has a plus and a minus connection which control the low frequencies as well as the medium-high frequency range. A SingleWire cable possesses one (+) plus and one (-) minus connection each on the amplifier and on the speaker side. SingleBiwire If the speaker has two plus and two minus connections in the rear terminals, the low frequencies and the medium-high frequencies can be controlled separately. For this purpose there are special cables that have one plus and one minus connection on the amplifier side - and two plus and two minus connections on the speaker side. The advantage of this type of connection over the SingleWire connection is that the low frequencies and the medium-high frequency ranges can be electrically uncoupled and so cannot influence one another. The amplifier output functions as the zero point through its dampening factor. BiWire In this variation, the speaker terminal also possesses two plus and two minus connections, separated into the low frequency and the middle-high frequency areas. However, instead of a SingleBiwire cable, two cables are used to control the two areas. This achieves an even better electrical uncoupling compared to the SingleBiwire solution as there is no possibility of influences and cross-talk inside the cable. In addition, the use of different cables for the low and middle-high frequency areas makes it possible to tune the tone quality of the?? set-up. So, if your cables have separate connections you should use either the SingleBiwire or the BiWire solution. In any case, both produce more detailed sound and more precision in the low frequency range. In their delivery state, BiWire speakers have “bridges” to connect the 2 pairs of terminals. Unfortunately these are usually made from cheap metal and thereby limit the potential of sound. If you cannot use the aforementioned BiWiring solution we recommend that you replace the cheap original metal bridges with high quality bridges such as the black&white ones. BiAmping even “bombards” both areas with separate amplifiers, thereby strongly improving the sound performance even more. By now, some speaker manufacturers even fit their speakers with TriWire terminals so that low, middle and high frequencies can all be controlled separately. |
|
|
The capability of storing electrical charge (energy) is called capacity. In cables this capacity is not wanted. The energy of the signal is supposed to be transmitted 100% and not stored.
By its very nature every cable possesses capacity. It depends on the construction and on the insulation material, where the dielectric constant plays an important role. In relation to capacity, air, or even better, vacuum, would be the best insulation. We have acted on this idea in the Atmos Air speaker cables and in our DUO-PE insulation. |
|
|
CC is the abbreviation of Concentric Copper and describes the special construction of the wires. As opposed to the chaotically arranged wires in bunched conductors, each wire in our concentric wires has a defined position. Exactly 36 wires are arranged exactly in three layers around one central wire. This has mechanical and sound advantages.
The regular arrangement ensures regular contact points between the wires. This causes a more homogenous signal flow and thereby a more precise and detailed sound. In addition, the CC wires are easier to process. The relatively thick wires cannot be cut off accidentally during de- insulation and the insulation is easier to remove thanks to the smoother wire surface. CC wires are also very stable and can be connected very easily to amplifiers or speakers with screwing or clamping connections without risking short-circuits. Of course we also recommend the optimum matching plugs or terminals for even contact. |
|
|
CEC, which stands for "consumer electronics control", provides a component and manufacturer-wide control function, such as "one touch play", "one touch record" or "system stand by". The prerequisite for this is that the relevant components of the chain support CEC. This also applies, for example, to HDMI cables. Not all cables on the market put through the CEC signal. All in-akustik HDMI cables however support this standard.
|
|
|
Cables are differentiated according to their construction. One of these constructions is the co-axial cable.
This construction has an insulation signal conductor surrounded by screening which is used as a return. The wave resistance of the cable can be influenced by the choice of dimensions and of the insulation of the conductor, the dielectric. An exact wave resistance (usually 75 ohm) is very important for all video and digital cables. |
|
|
A condensator is an electronic component that is enabled by its capacity to store electrical energy. Unlike in cables, this effect is desired in conductors.
Unlike a battery, a condensator can, depending on its dimensions and construction, absorb large amounts of energy in a very short time and also give them out again. This ability is used specifically in car hi-fi systems. Power caps provide power peaks of several hundred ampere at high sound volumes which could not be provided by batteries alone. Using a good Power Cap offers noticeably more power and dynamics. They are one of the best tuning measures for car hi-fi systems. |
|
|
The ability of a material to transport electricity is called conductivity. Every material has its own specific conductivity, the conductance. This expresses how long a conductor with a square millimetre cross-section is that possesses exactly one ohm resistance. The longer the wire can be, the better its conductance.
Silver has the best conductance under normal circumstances, 62 m/Ohm x mm². Copper is number two with 56 m/Ohm x mm². As conductance is heavily dependant on the purity of the material we were able to improve conductance of MGC to 59,1 m/Ohm x mm²! |
|
|
The current bearing part of a cable is called a conductor. It has to be made of a conducting material such as copper or silver.
A conductor is called a wire, and can be solid and non-flexible, or be made from many single very thin wires and be flexible. The conductor that is covered in non-conducting material and is thereby insulated is called a strand. |
|
|
In plugs, the electrical connection is established merely through the touching of contact surfaces. The quality of the connection can be expressed in the contact resistance. Poor contacts have a high contact resistance and cause high signal losses. Special surface treatments, such as gold-plating, reduce contact resistance and improve the contact quality.
|
|
|
The amplifiers of car hi-fi systems are automatically switched on with the radio. In order for this to function, the amplifiers must be connected to the car radio through a control wire, also called a remote wire. The C-NF20, for example, has this additional control wire.
|
|
|
Converters are active adapters that transform the incoming signal. They make it possible to connect devices whose connections do not fit together. One example are the Opto to Coaxial converters. They transform electrical signals into optical ones( means: light impulses) and vice versa. This way, a DVD player with an optical digital output can be connected to an AV receiver with a co-axial, so electrical, digital input.
|
|
|
Copper is the most commonly used conductor material.
But not all coppers are the same! There are great quality differences in purity. Normal electrical cables are made from E-CU, which contains oxygen. It is sufficient for this purpose. But hi-fi and video connections require better quality copper, as copper containing oxygen can oxidise. Conductivity is also impaired. Electrons flow through copper like cars drive on the motorway. Impurities and inhomogeneous crystalline structures impede the power flow in the same way as bad road conditions and road works impede traffic. Impurities in copper are described as interference points. The signal transport gets worse the more interference points are on the conductor. Road works on the motorway disturb not only the traffic directly around them but also cause traffic jams that can be several kilometres long (for example, the building site is only 100m long but the traffic jam is 10km long). It is similar with copper. One single alien atom „tenses“ the crystal structure of wide areas and impairs conductance. OFC (Oxygen Free Copper) can already improve conductivity greatly. PC-OCC copper describes copper with a mono crystalline structure (the wire consists of one single copper crystal without Korngrenzen), which is achieved by a special melting process. MGC (Medical Grade Copper) is very pure copper. Not only the oxygen content but also any other impurities are important here. They are expressed in ppm (parts per million). This is how many alien atoms are contained per 1 million copper atoms in the material. For the LS-1602 several highly pure loads of copper were thoroughly tested, and an extremely pure load with the following amazing values was selected: Chemical analysis (impurities): 30 (ppm) Coil: 465 (mm)* *Impurities under 30 ppm cannot be measured exactly in laboratories. The coil test is used to analyse the purity of material when it is below this level; it cannot measure absolutely, but it can compare different loads. In these tests, one exactly shaped copper coil from that load is pulled apart with a set force. The further the coil stretches, the purer the copper. Values of about 430mm are standard. Is it worth the effort? Yes! The copper was examined in a laboratory for its properties as an electrical conductor. The result is astounding: The conductance is 59.1 (m/ohm x mm²), as opposed to that of standard copper, which is 58 (and used to be 56) (m/Ohm x mm²) . This is 2 % more, which is a great deal in this area. |
|
|
The surface area of a severed conductor is the cross-section and is specified in mm² (not to be confused with the diameter). The cross-section is then the area available to the current in a conductor. It is comparable to the lanes of a highway. The more lanes there are on a highway, the better the flow of traffic.
In loudspeaker cables, the cross-section plays an important role since relatively large currents must be carried. The effective cross-section is affected by the “skin effect”. |
|
|
In cables with CSP technology, the surfaces of the conductors are plated with pure silver. In wires and CC concentric copper, each single wire is individually silver-plated. The background to this technology is this:
The skin effect means that high frequencies are transmitted mainly on the conductor surface. As silver is usually the best conductor (even better than copper), high frequencies have better conditions in silver-plated conductors and can be transmitted with fewer losses. In audio and speaker cables, silver-plated cables emphasise the high frequency area. It is a good way to improve old systems or systems with pale and lazy sound. Digital and video connections are ideal for silver-plated cable constructions. These extremely high frequencies move almost exclusively on the conductor surfaces. Here, the silver reduces losses extremely. The focus, contrast and colour of the picture are preserved. Even over longer cable runs. |
|
|
The data rate specifies how much information is transmitted in what time. In the digital age, this is described by bits and bytes.
So, data rate is measured in bits per second. In digital sound outputs (co-axial or optical, also SP/DIF) the data rate can reach up to 1536 kb/s. In digital picture (Video) outputs (DVI and HDMI) even up to approximately 9 Gb/s! |
|
|
Unlike analogue signal processing, digital signal processing transmits and processes the information as a string of combinations of zeros and ones (binary code). Analogue information is measured, and the individual values are stored in strings of numbers. A CD with a reading rate of 44,1 KHz for example reads 44.100 values per second and saves them as numbers.
The DA (digital to analogue) converter reconstructs these string of numbers back into analogue signals, which are then made audible by, for example, an amplifier. The advantages are that the stored data ( strings of numbers) do not lose quality (think of various records that get scratched or tapes that wear out), and that the data can be transmitted with fewer losses, at least theoretically. In addition, the possible quality, especially of dynamic range and band width, is noticeably better for digital storage and processing than for analogue media. Nonetheless, there are still many fans of completely analogue technology in the High-End sector. Indeed, love of technological progress apart, this analogue sound quality has its own peculiar charm. |
|
|
The transmission of digital data between devices requires special cables. There are two kinds of digital cables: Co-axial and optical ones.
In co-axial digital cables, digital data (ones and zeros) are transmitted by electrical current. Because of the very high transmission frequencies these cables need special properties. One important feature is cable impedance (or wave resistance). This must be 75 ohm to ensure optimum transmission. This fact makes the co-axial digital cable into a relative of the video cable with the same impedance of 75 Ohms.. In optical digital cables, the digital data is transmitted by light. This requires special converters that transform the electrical impulses into light and then back again. A TOS link connection is usually used in AV devices. Unfortunately, the quality of this type of connection is not the best. Reflections in the plugs interfere with the data signal and irritate the error correction of the D/A converter. So we recommend: use a co-axial digital cable if your devices have co-axial out- and inputs. For the sake of sound! |
|
|
In vehicles, the battery is often housed in the engine compartment and the amplifiers and diverse electronic components for car hi-fi installations are stored in the trunk.
To minimize costs and save space, it is recommended to lay an appropriately thick battery cable from the battery to the trunk and connect it with the separate devices through a distributor block. Depending upon the installation, the grounding cable should likewise be directly connected with the battery and not, as is customary, merely attached somewhere on the car body (see also Car Hi-fi Guide).
|
|
|
The insulation material influences not only the basic construction but also capacity and electrical loss of the cable. The selection of the correct material is a deciding factor in transmission quality. in-akustik has developed DUO-PE insulation for the black&white / Reference series. For this insulation we use high quality PE (polyethylene), which has outstanding electrical properties. These properties are improved when the PE is enriched and foamed with air.
DUO-PE insulation consists of one layer of foamed polyethylene for the optimum electrical properties and one layer of solid polyethylene as protective cladding. DUO-PE II is the improved version; the air content in the foam has been increased to further improve the properties. |
|
|
DVI is short for Digital Video Interface. It originates from the computer sector. There are different kinds of interface:
DVI-I = digital dual link plus analogue picture signal (RGB) DVI-I SL = digital single link plus analogue picture signal (RGB) DVI-D = pure digital dual link picture signal DVI-D SL = pure digital single link picture signal The dual link versions offer two data channels, so twice the possible data rate (up to 9 GB/s) can be transmitted. In home AV systems the DVI-D version is the most common. However in the mid-future, DVI will probably be replaced by HDMI. |
|
|
Cables and device housing act like antennae and “receive” a multitude of interferences. This causes differences between the “potentials” of the devices, which can cause balancing currents and interferences with the actual signal. Ferrite cores or absorbing ferrite in the cables offer high resistance for very high frequencies and considerably reduce balancing currents. The actual signal can be transmitted more cleanly. In addition, the device inputs are not loaded with “dirt and noise” that is not suitable for them.
|
|
|
Filters can be used to influence the transmission properties of a cable. It is possible to select one of the signals to be transmitted. There are low pass (transfer of low frequencies), band pass (transfer of a defined frequency range somewhere between the low and high frequencies) and high pass filters (transfer of high frequencies).
Usually cables belong to the low pass variation and so transfer high frequencies less well. Special construction and material selection can improve this behaviour and adapt the cables to the desired use. Sometimes, additional electronic components and ferrite are used to influence the transmission area and so filter out unwanted interferences. Power cables and power bars are an example. |
|
|
Full HD describes the resolution capacity of the components. Components marked with the “Full HD” logo need to provide a native resolution of minimum 1920 x 1080 pixels and can handle “Progressive Scan”. Full HD is a further development of “HD Ready” and is currently the highest resolution format.
|
|
|
Fuses serve to protect the devices and prevent damage to persons or equipment in the event of malfunctions, etc.
For car hi-fi systems, fuses and fuse holders are used primarily as conductor protection and have to be adapted to the cable cross-section and directly mounted with the battery. In the event of emergencies, they prevent dangerous cable fires. The same applies to installations in the home. CAUTION: only trained specialists may perform this work! Generally, we also recommend having car hi-fi installations performed by specialists. |
|
|
A music signal creates current flow in an audio cable.
This current flow creates a magnetic field, which induces a voltage in the neighbouring conductors (e.g. shielding). If this induced voltage is short-circuited (e.g. due to a radially closed shielding), a second electrical circuit (secondary circuit) is generated, which “weakens” and distorts the original musical signal. The current in the secondary circuit also creates a second magnetic field, which induces a voltage back into the signal conductor. This voltage overlays and influences the music signal. The coaxial standard shielding of conventional audio cables function like short-circuited secondary circuits. Eddy currents arise which alter the music signal. The dynamics are diminished and the hi-fi system sounds flat. The newly developed GAP shielding of the black&white NF-1202 and NF-1302 is not radially closed. Instead it is slit and so does not cause unwanted secondary circuits. All of the power and dynamics of the music remain intact. Nor is the music overlaid with “reflected” inductive voltages. Silence falls in the concert hall, so to speak. |
|
|
Gold is a rare metal that is always in high demand. In the area of electrical contacts gold has another very important meaning.
Gold can adapt to another surface down to the level of atoms, thereby increasing the effective conductive surface. This reduces transmission resistance and improves the quality of contacts. In addition, gold prevents the contacts from oxidising and so guarantees lasting low contactresistance. |
|
|
HD Ready describes the resolution capability of the components. “Full HD” marked components need to provide a native resolution of min. 1280 x 720 pixels. They also need to have min. 1 analogue YPbPr-Component connection and min. 1 HDCP compliant digital connection (DVI or HDMI).
|
|
|
HDCP stands for High Definition Content Protection. It is a type of copy protection that has been introduced for the new digital video interfaces DVI and, especially, for HDMI.
Source devices such as DVD players and digital Sat receivers can only emit the high resolution picture data in a copy-protected state. Display devices (TVs, plasma TVs, projectors etc.) that have an HDMI input can always process HDCP copy-protected signals. Devices with the “HD Ready” symbol can also do this. Devices that have a DVI input are however not necessarily capable of processing this copy protection. These devices can naturally not process copy-protected material. The picture stays dark. Always make sure that the device with a DVI input is capable of processing the HDCP copy protection before buying it or connecting it to a digital source. |
|
|
HDMI is the new digital interface for video and audio for AV devices. HDMI stands for High Definition Multimedia Interface. Up to now digitally stored video and audio data have been converted into an analogue signal by a D/A converter and transmitted to the TV. There was nothing wrong with this, since with valve devices image processing mainly also took place in the analogue domain. This does not make sense anymore however, due to the development of new digital display technologies such as LCD, plasma or DLP. The digital information would be initially converted into an analogue signal and then subsequently converted back into a digital signal. Of course, it makes more sense for the digital data to be transferred from the source to the digital display without modification. This is exactly what HDMI does, whereby HDMI is an advancement of the DVI interface from the EDP area.
Since the HDMI interface provides video and audio content in absolutely perfect high-resolution quality, a condition has been imposed by the software industry that the data may only be output in a copy-proof and copy-protected manner. This is why the HDCP copy protection is used here. The newest HDMI Standard 1.3 is designed for a picture resolution of up to 1080p and simultaneously for up to eight audio channels in 24 bit / 96 kHz. This standard includes also the Lip Sync function. The extremely high data rates of up to 10,5 Gbit/s is a big challenge for the cables. Furthermore, the standard was originally developed for a maximum cable length of 5 m(DVI). An extended length can be fully utilised however, due to the optimised design, materials and manufacturing quality. The Matrix S1, for example, works up to a length of 15 m at full HDTV 1080 p resolution. All of our HDMI cables correspond and comply with version HDMI 1.3 and also support the CEC remote control function. Incidentally, the wheat is separated from the chaff here. The HDMI organisation discerns between two cable qualities only: Standard HDMI cable and High Speed HDMI cable. |
|
|
HDTV is the standard of future television (High Definition Television). This is high resolution television with picture quality not seen by consumers before. The usual PAL Standard, for example, uses 576 visible lines. HDTV increases the resolution to up to 1080 lines.
Source devices may only transmit the full HDTV resolution in a HDCP copy-protected state, through digital DVI or HDMI interfaces. So if you want to enjoy high resolution television, your devices need the corresponding interfaces. These are recognisable by the “HD Ready” symbol. You should also use the matching cable. It's worth it! |
|
|
Inductivity stores energy magnetically. Before an inductivity (coil) conducts electricity it builds up a magnetic field. The time this takes depends on the inductivity value (size). Higher frequencies mean that there is less time to form magnetic fields, and the current intensity decreases. Inductivity is basically a frequency-dependent resistance. Cables by their very nature possess inductivity. In speaker cables especially this inductivity influences sound through the low speaker impedances. For this reason, the unwanted inductive factor should be as low as possible in speaker cables. We have developed, among others, PETS technology to achieve this. In our active speaker cable LS-A1 the inductive factor is completely compensated.
|
|
|
Cables are insulated to prevent short circuits while they are being laid. The actual conductor is covered in a non-conducting material, the insulation. The insulation has more than one purpose. It should be stable to protect the cable from damage and corrosion. Depending on the use, it should be flexible or rodent proof.
In the hi-fi and video area, the electrical properties are the most important. Unfortunately not every conducting material is able to store electrical energy; this is expressed in the specific dielectric constant. A good example is a fully synthetic pullover that lets off a veritable thunder storm when it is taken off. This storage effect (capacity) is not wanted in audio and video cables as they are supposed to transmit the electrical impulses and not store them. Source devices such as hi-fi amplifiers can also react badly to cables with high capacity. The best insulation material is air. This is why in-akustik has developed techniques such as DUO-PE or Atmos Air, which use air as insulation material. |
|
|
Interferences are the result of mixing signals (frequencies). The process can result in completely new signals. It is a bit like mixing colours: yellow and blue make green.
If several signals can influence one another because of a lack of screening, mixed signals can result that bear no relation to the actual signals transmitted.
|
|
|
Conventional tube TV’s „write“ their pictures by means of an electronic ray to the glass display: point by point and line by line. The picture drawing starts in the upper left corner and ends in the lower right corner. This way of “drawing” from the first to the last picture point certainly takes some time. At the beginning of the TV area, when the Electronics still were a little more slow and the human eye could perceive this time laps between the first and last line as some kind of Jitter. That’s why some trick was applied: instead of transmitting full pictures (progressive) – line by line – so called ½ (half) pictures of the odd and even lines respectively were displayed. Doing so the screen was twice fully filled at the same time, and this without needing a higher transmission speed ( = higher bandwith). For the human eyes that looked as an almost jitter free picture.
Today’s electronics outspeed yesterdays: that’s why today full pictures can be scanned and displayed line by line. That’s what is called “Progressive Scan” and the advantage is a clearly improved and sharper picture. |
|
|
During digital data transmission ones and zeros are transmitted by voltage impulses. Threshold values are used during transmission to determine whether the bits are zeros or ones. For example, 0 - 0.5V are interpreted as zero and 4.5 - 5 V as one. This process gives more security during transmission, but it cannot compensate another important factor: Time!
In serial data transmission, which is used for audio and video data, bits are transmitted and received consecutively. The choice of one or zero is made by the length of the impulse (e.g. long impulse – one, short impulse = zero). The Jitter effect changed the impulse length due to the cable properties. The receiver then has difficulties in recognising the data. Where bad digital cables with a strong jitter effect are used, the D/A converter has to use its error correction often which impairs the playback quality. |
|
|
The separate digital signal processing of picture and sound may cause a visible time shift. The Lip Sync function of HDMI 1.3 equipment compensates this effect.
|
|
|
Magnetic fieldWhen a current flows through a conductor, a magnetic field is formed around it. As the magnetic field builds up, it induces a voltage back into the conductor. Due to its opposite polarity, this inductive voltage slows the flow of current and allows only a slow rise in the current intensity.
The faster the direction and intensity of the current changes within a conductor, i.e. the higher the frequency, the more the current flow is hindered through the self-induction. A frequency-dependent resistance develops (see also under “inductivity”). However, the magnetic field not only induces a voltage in its own conductor but also in adjacent ones. If the conductors are not adequately shielded, “crosstalk” can occur, i.e. the signals in the adjacent conductors superimpose on each other and interferences are caused. The effect can however also be used to advantage to reduce the inductivity of a cable. The initial and return conductors are laid close together so that their magnetic fields are mutually neutralized. This is used, for example, in all black&white Reference loudspeaker cables. |
|
|
The magnetic fields caused by the flow of current in the cables exert mechanical forces on one another that can cause vibrations in the cables. These tiny mechanical vibrations are called micro vibrations. They constantly alter the cable parameters and thereby influence the transmission quality.
Stable and compact construction, such as that used in the Delta Profile of the Atmos Air cable or the PE-Network Jacket in the black&white reference products reduces micro vibrations and improves the transmission properties. Especially bass dynamics and precision of large speakers profit from these measures. |
|
|
This patented technique uses a metal band to screen the conductors from one another. The advantage is that the conductors cannot interfere with one another. Without the MSR technique, the magnetic fields cause a kind of displacement of the electrons in the conductor, thereby causing a concentration of current on the outer edge of the cables. The MSR technique prevents this, the current is distributed evenly and the effective conductor cross-section increases. This technique is used in the cables from our Cobra series.
|
|
|
As opposed to coaxial digital cables, optical cables do not transmit data with electrical impulses but with light pulses.
Normally, TOS-link plug connections are used for audio/video components. This type of optical data link is unfortunately not comparable with industrial light conductors. The mechanical design of this plug standard is much more primitive, which translates into considerable losses in quality. In addition, the actual electrical data signal must first be converted into an optical signal and back into an electrical signal in the receiver. If you have the choice between optical and coaxial digital cable components, the coaxial version is in any case preferable for better sound. NOTE: The optical and coaxial digital audio outputs only transmit sound and no picture! |
|
|
The PE network jacket (PENJ) is a braid made of polyethylene monofilaments which serves two functions:
First of all, it reduces the capacity of the cable, since this is also dependent upon the material used in the insulating coat (with non-shielded cables). Secondly, it reduces the micro-vibrations in the cable, since it is applied very tightly and holds the wires very compactly together. PENJ is used for second generation black&white / Reference products. |
|
|
All cables possess inductivity, a resistance which influences the transmission of the music signal in relation to the frequency. PETS (Polyethylene Tube Support) technology reduces this inductivity to a minimum.
The current flowing in a cable builds up magnetic fields that can neutralise one another depending on their alignment and positioning. The strand pairs circle around the PETS carrier material, forming a kind of waveguide. This unique configuration intentionally creates an overlapping of the magnetic fields. The magnetic fields for the positive and negative cables are counter rotational as the result of the opposing direction of electrical flow. In the area where they overlap, they cancel each other out. This considerably reduces inductivity. The music signal can reach the sound transformer unimpeded. |
|
|
Electronically displayed pictures consist of a huge multitude of single picture points. These “picture points” are called “Pixels”. The more detailed a picture needs to be displayed, the more pixels are needed and consequently the higher is the resolution. Actually: in modern Colour Displays each Pixel itself again consists in reality of 3 pixels: red, green and blue (RGB). The final colour to be displayed results from a mix of these individually actuated 3 basic colours.
|
|
|
Every cable requires its special plug adapted for the corresponding application. Plugs are the interface between the device and the cable. Differences in quality, not to be underestimated, are also found here. These range from sharply pointed plastic plugs to solid metal plugs, with plated or bare surfaces. At in-akustik, all plugs are gold-plated since gold has the best contact properties.
A special form is the TOS link plug for optical cables. It transmits light instead of current. With this plug, a perfect fit and a cross-section polished to a precise angle is extremely important, since otherwise reflections could occur in the light conductor and disrupt the receiver. |
|
|
Polyethylene (PE) is a very high-quality insulating material (dielectric) with properties that make it excellent for audio/video cables. It reduces the capacity of a cable better by a factor of two over PVC (polyvinyl chloride). The electrical loss of PE is likewise very limited. These properties are further improved with DUO-PE technology.
|
|
|
These are not to be confused with the power cables of computer systems.
Nowadays the quality of audio and video components has reached such a level that any change in the chain is visible and audible. Even the improvement of power provision improves the general result. Interferences, or electro-magnetic waves, are caused by almost every electronic device. If electronic appliances are fed with signals that are not suitable for them, they tend to produce “strange” effects. Particularly high-frequency interference originating from, for example, mobile phone radiation, computers, radio communication traffic etc. superimpose themselves on the original signals in the circuits. They lead to interference. Sometimes they displace the operating points of various components. These effects in audio and video appliances lead to a "blurring" of the picture and sound quality. That is why power cables from the black&white Reference series are screened and possess their own In-Plug filter which suppresses interfering impulses from the power grid. |
|
|
Like Interlaced
|
|
|
Digital and video cables must be adapted due to the height of the frequencies they are to transmit (wave resistance). If not, reflections can occur. When reflections occur, a part of the sent signal does not arrive at the receiver and is reflected back to the cable. A kind of echo superimposes itself over the original signal in the cable. One can get an idea of this effect by thinking of an indoor pool area, where everyone is yelling at once and you can’t hear your own voice. The receiver naturally has extreme difficulty in correctly interpreting the sent information. This causes losses in quality. At worst, malfunctions occur.
|
|
|
The resistance of a cable impairs the signal transmission and leads to signal loss. It should therefore be as low as possible. The resistance is dependent upon the conducting material used, the cross-section and the frequency of the signal to be transmitted (skin effect).
|
|
|
The resolution describes, how detailed an electronic device (camera, TV, LCD) can display a picture. Normally this is defined in Pixels: the more pixels such a device can provide – the more detailed a picture can be displayed. Standard resolutions in HDTV are for instance: 1280 x 720 (HD Ready) or 1920 x 1080 (Full HD). Camera resolutions however are mostly described in “n” Million Pixels.
|
|
|
The time that a signal takes to get from the source to its goal is called runtime.
The human ear takes in spatial information by runtime differences. For this reason, the speakers should be set up equidistant from the listening place. Cable lengths between individual speakers and the amplifier should also be equal to avoid runtime differences and ensure precise playback. This can be difficult as the amplifier is often not in the exact middle of the speakers. Even in this case you should still use cables of equal length. The extra length of the shorter side should not be coiled but instead laid out evenly on the floor in snaking lines. It's worth it. |
|
|
Many of the signals transmitted in hi-fi and video systems are very small and weak. They are easily distorted by external electric and magnetic fields. This is prevented by shielding. The cable is constructed like a sort of Faraday cage, in which the signal can be protected during transport. The effect (the degree of shielding) is measured in dB and describes the reduction of any interferences.
There are great differences in the structure of cable shielding, and in the effect. The simplest type is a spiral shield. Here, several wires are wound around the conductor(s) in a spiral. The effect is just about sufficient. In braided shielding, wires are intricately braided around the conductor. The result is that more surface is covered and so a better shielding effect is achieved. The film/foil shield is another version. In this case a Mylar foil, usually coated with aluminium or copper, is wrapped around the conductor(s). Grounding is done by a nude, uninsulated wire. . Ideal shielding is achieved by combining various techniques. Double and triple shieldings combine spiral, braiding, and foil shielding to improve the effect. in-akustik’s SCDS technology (System Closing Double Shielding) combines foil shielding with a very dense braided shield and thereby achieves very good results. GAP shielding is an extremely high-end shielding version. It is constructed to prevent eddy currents that could irritate the sensitive audio signal. This is why the shielding is not completely closed radially but instead is leaving a gap. |
|
|
With an increase in the frequency, the current in a conductor increasingly flows only on the surface of the conductor, whereby the effective conductor cross-section sinks. Thus, with a loudspeaker cable of 6 mm², the full 6 mm² is only available to the bass ranges while the treble range can only use approx. 2 mm² due to the skin effect. This is the reason cables with a large cross-section sound somewhat “bass-heavy”. Special technologies such as CSP or PETS serve to minimize the skin effect.
|
|
|
Usually, solid conductors, so conductors made from only one wire, sound more direct and precise than those made from more wires. This is because the multiple wire version has no defined contacts between the separate wires and the electrons can move chaotically between them. This means that impulses are transmitted imprecisely.
DSS conductors, our solid conductors, do not have any undefined conditions so current is transported homogenously. In the area of digital and video transmission DSS conductors have an additional advantage: The very smooth surface (DSS = Direct Signal Surface) enables the wave resistance of the cable to be set exactly so that the high signal frequencies that move mainly on the conductor surface are transmitted in the best way. |
|
|
The connecting cable between an amplifier and a speaker is known as a speaker cable. Like all cables is should be constructed specially for its purpose.
As a speaker cable must be able to transmit quite large streams very precisely it requires, unlike audio cables, a relatively large conductor cross-section, to minimise loss of sound and power. Intricate constructions such as DUO-PE, PETS and PE-Network Jacket, as well as high quality materials such as CC (Concentric Copper), OF copper and MGC, improve the sound performance even more. |
|
|
Proper home cinema sound can only be delivered with a subwoofer. A special subwoofer cable connects the subwoofer with the subwoofer output of the surround sound amplifier. Depending upon the subwoofer input (stereo or mono), the appropriate cable version is available (one-to-one or one-to-two cinch plugs). The output on the surround sound amplifier is usually of a mono design (LFE).
|
|
|
Surround sound is an English term based on the verb “to surround”. The name is indeed appropriate! The term usually refers to a sound system that is set up so that the listener is encircled and pulled into the center of the action.A surround sound system consists of several loudspeakers (now up to seven plus subwoofer) and a corresponding surround sound amplifier. The loudspeakers are arranged around the listener and produce the appropriate sound field. There are various “virtual surround” solutions that generate a surround sound effect with only two loudspeakers. These do not however approach a discretely designed solution by any means.
|
|
|
With symmetrically designed cables, two exactly identical wires are used for the initial and return conductors. This construction provides an extremely high immunity to interference, since electromagnetic interferences cancel each other out. Normally, a separate shielding additionally protects the signal. The origin of this technology is the professional stage. Since dynamic microphones only send a tiny signal that is very easily disturbed, an interference-immune connection must be established. The many sources of disturbance, such as light, amplifiers, distributor boxes, etc., which are often in use on a stage, added to the problem. Nowadays, symmetrical cables, also referred to as twisted pairs, are even used as network cables for computer connections.
For audio systems, symmetrical Cinch and XLR cables likewise improve the transmission quality.
|
|
|
Teflon is considered the best insulation material (dielectric) one can use for audio/video cables. In its pure form, it is actually even better than polyethylene. Nevertheless, in-akustik has developed a DUO-PE technology for the black&white / Reference line with properties that surpass those of Teflon.
|
|
|
These refer to electronic tubes. Despite their “age”, these harbour fantastic audiophile properties that cannot be established by other electronic means. From a purely technical standpoint, tubes are in fact inferior to all modern transistors, yet they sound very pleasant and natural. The reason for this is the “noise spectrum” produced by the heated glass tubes.
|
|
|
Video connections are also generally called video cables. There are different analog and digital signal standards which vary considerably in transmission quality. Thus, the choice of a connection standard is very important. The following is a list of the most common versions, starting with the most simple:
Composite / Video / FBAS (analog) This is the simplest form of video connection. All required picture signals (red, green, blue, H-sync, V-sync) are contained within a single signal. This naturally results in substantially reduced quality. S-Video (analog) This version divides the picture signal into separately transmitted brightness and color signals. A clear improvement. Component / YUV (analog) This version transmits the picture signal in three separate lines (brightness, blue minus brightness and red minus brightness). It functions nearly without any loss in regard to the converter. RGB (analog) The RGB signal carries all relevant picture signals separately and is the highest quality analog connection. Scart A fully wired Scart cable transmits all analog transmission types plus the sound as well as diverse control signals for communication between devices. A Plug&Play solution. DVI / HDMI (digital) The newest connection types are called DVI and HDMI. They provide a fully digital transmission of the picture and are therefore only found in digital devices. Tip: In order to establish the best possible connection, you should first determine the highest quality signal standard with which the devices to be connected are compatible. |
|
|
The wave resistance, or impedance, is an important cable parameter calculated from the ratio of inductivity to capacity. It is specified in units of Ohm (W) and standardized in most video and digital cables with 75 Ohm. If the devices and the wave resistance of the cable do not match, reflections occur.
|
