Cable Direction for Audio Cables

Your cable has an arrow printed on it. The arrow tells you the direction in which you have to connect your cable between equipment.Most people familiar with hi-fi sound equipment will be aware of cables that have been specially marked by the manufacturer to show the optimum direction for connection. In most cases we assume that “the manufacturer knows best” and follow the instructions implicitly. Some manufacturers, who target their cables towards hi-fi perfectionists, will advise auditioning the cable in the preferred direction for a short time, then comparing the sound quality in the reverse direction, and permanently connecting the cable in the direction that sounds best.

Just how important is cable direction to the enjoyment of music?At Black Rhodium we consider it very important.We have found by our own research that lengths of the same wire will sound different if they are reversed. Although ‘wire direction’ characteristics can be considered as being due to uneven cooling as the wire is being drawn, we have found no reliable scientific explanation for this phenomenon, but our ears are sensitive enough to hear a difference.

Follow the direction of the music current

If we make up a single speaker cable using the same wire, the sound will be clearer if the positive and negative conductors are in the opposite direction – so that the current in the wire sees the same direction in the wire as it travels from the amplifier to the loudspeaker and back again.

Wire direction found in most manufactured cables

Most loudspeaker cables, and balanced interconnect cables, are manufactured with the wire ‘direction’ in the same direction for both signal and return connections as in the diagram below.
>>>>>>>>>>>>>>>>>>>>> +ve

>>>>>>>>>>>>>>>>>>>>>> -ve

Wire direction for better sound quality

If, as may be possible with a simple ‘twisted pair’ cable, the wires are separated and the signal and return connections rewound in opposing directions, the sound will become clearer with a deeper background silence between musical notes.

  >>>>>>>>>>>>>>>>>>>>>> +ve

<<<<<<<<<<<<<<<<<<<<<<< -ve

This has important implications in the manufacture of all audio cables.In the case of manufacture of a simple 2 core speaker cable, it is most likely that both cores are in the same direction. But this cannot always be guaranteed. If an audio cable supplier wishes to improve the sound quality by quality control of the wire direction, then two separate processes need to be defined.Firstly the full batch of the cable manufactured must be made from the same supply reel. If two reels are used, no one will know if the ‘direction’ information in the wire is the same for both reels.

Secondly the cable manufacturer needs to set up a reliable quality process that ensures that all the wires of one colour are reversed during the process and none of the other colour. Any divergence from these principles will result in inconsistent sound quality within the batch.

Reversing both cables in a sereo pair

If both cables in a pair of stereo cables are reversed, there is an audible difference in the sound.

In our experience this is not sufficient to warrant a prescribed view on which direction the cables should be connected. We do recommend our customers to make their own tests if they wish, but our goal is to give our customers the very best sounding cables without any technical effort on their part.

Wire direction of most stereo cables

>>>>>>>>>>>>>>>>>>>>>>+ve Left

>>>>>>>>>>>>>>>>>>>>>>-ve Left

>>>>>>>>>>>>>>>>>>>>>> +ve Right

>>>>>>>>>>>>>>>>>>>>>> -ve Right

Wire direction if both cables are reversed

<<<<<<<<<<<<<<<<<<<<<< +ve Left

<<<<<<<<<<<<<<<<<<<<<< -ve Left

<<<<<<<<<<<<<<<<<<<<<< +ve Right

<<<<<<<<<<<<<<<<<<<<<< -veRight

This is a stereo cables with both channels reversed. Some experts suggest that you should test your cables in both positions and chose the position that sounds best

We take the view that all cables should, as by convention, be connected with the printed writing on the cable reading from left to right when connected from a source signal (CD player, turntable, tuner etc) on the left to and amplifier on the right. For speaker cables we suggest that the writing on the cable reads from amplifier to speakers. When cables are to be connected one way only, for example a BiWire speaker cable, we assemble the cable so that its reads from amplifier to speaker.

Wire direction for best sound quality

If we design a pair of speaker cables in which the positive and negative wires run in ‘opposite direction’ then if we reverse one speaker cable without reversing the other we find quite a significant deterioration in sound quality. The effect is as if a layer of background noise has modulated the music. The sound is less sharp and less in focus.

>>>>>>>>>>>>>>>><>>>>> +ve Left

<<<<<<<<<<<<<<<<<<<<<< -ve Left

>>>>>>>>>>>>>>>>>>>>>> +ve Right

<<<<<<<<<<<<<<<<<<<<<< -veRight

This is a Black Rhodium stereo cable as it would normally be connected. This is the best connection for consistently good sound quality.

If we reverse one channel, without reversing the second channel, the sound is severely degraded and will sound audibly distorted by comparison.

  >>>>>>>>>>>>>>>>>>>>>> +ve Left

<<<<<<<<<<<<<<<<<<<<<< -ve Left

<<<<<<<<<<<<<<<<<<<<<< +ve Right

>>>>>>>>>>>>>>>>>>>>>> -veRight

By reversing one cable of the pair, the sound will be degraded with a loss of focus in the music. When you return to the correct configuration, a layer of background noise appears to be removed.

Wire direction  for optimum sound in Black Rhodium cables

At Black Rhodium we do not wish the sound quality of our cables to vary, with some cables sounding inferior to other of the same type.

We have devised a series of high quality manufacturing processes which we have agreed with our UK based suppliers.

  1. For any order of cable we stipulate that the whole production batch is manufactured from a reel containing a single unbroken length of wire as supplied to them.
  2. We request that the first layer of insulation on the wire has an arrow printed on it to identify the direction of the wire as it comes off the wire manufacturer’s reel.
  3. From this position we can specify exactly the direction of each wire in each cable.

This enables us to design speaker cables in which the positive and negative wires are arranged in opposite directions.

March 15, 2018

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Deep Cryogenic Treatment of Audio Equipment

What is Deep Cryogenic Treatment?

Deep Cryogenic Treatment (DCT) is the process of cooling an object in a low temperature vessel to a very low temperature, typically that of liquid nitrogen at -196oC, keeping the object at that temperature for a period of time and then raising the temperature back to ambient temperature.

The purpose of applying deep Cryogenic Treatment is to improve the properties of the item being treated. In the case of audio cables and other audio equipment, the justification for Deep Cryogenic Treatment is the improvement in sound quality.

The Deep Cryogenic Treatment Process

Deep Cryogenic Treatment is usually applied in three separate stages.

Cool down. The cables are very slowly cooled over several hours at a pre-defined rate to the desired temperature.

Soak at low temperature. The cables are held at low temperature for a long period with precise temperature/time profile that has been tested to deliver superior audio sound quality.Maintaining the temperature at -196oC for at least 24 hours ensures complete transformation of the full cross section of the object being processed.

Return to room temperature. The temperature is slowly and carefully returned to ambient.

Computer control. All these DCT processes are controlled by a pre-defined computer programme to ensure consistency in performance for each process.

Description of the Deep Cryogenic Treatment used for audio

The ‘dry’ treatment. The cables and connectors are cooled in nitrogen vapour. It is important that all moisture and air is removed from the cooling vessel so that all that remains is an inert Nitrogen atmosphere. If any condensation occurs during the process sensitive electrical parts and materials could be damaged. So some cryogenic processing suppliers may use different vessels for audio than for other industries.

Another factor that affects the quality of the treatment is that different vessels should be used for different materials. When automobile parts are processed, the lubrication on the tools and engine parts is dispersed throughout the cooling vessel. It is impossible to remove all the petrol based lubricants could settle on the audio grade silicone and polymers on a subsequent processing, causing premature perishing.

Types of Products that Benefit from Deep Cryogenic Treatment

Products that are formed from a molten state

Most of the materials that are used in audio such as metals, plastics and glass begin life in a molten statewill benefit. As they are formed into shape, they are then allowed to cool. In most manufacturing processes the cooling is engineered to occur as quickly as practical to keep manufacturing costs down. As some parts will cool quicker, stresses in the material will develop due to the differential cooling rate. These stresses will cause mechanical weakness and will impede electron flow in conductors. Further processing post manufacture will further change the material crystal structure. Glass and plastics may be moulded. Metals may be milled, sawn, bent or sanded to achieve their finished state. All this additional processing can cause further irregularities in the crystal structure.

Why further heat treatment is not as effective

The most common way to relieve the stresses caused during manufacture is to heat the material until the atoms can move more freely and then cool down.However there is still the danger of new stresses being created in the material as it cools down.

Deep Cryogenic Treatment relieves stresses in materials

DCT processing relieves manufacturing stresses more effectively by the removal of energy. As the material cools, the atoms are bonded more closely together, removing any distortion in the atomic structure. New material stresses are avoided by controlling the cooling in a very slow controlled manner. As the materials returns to room temperature the structure formed at low temperature will remain. This new structure has less stress and responds to energy such as the electrical signal representing a musical performance in a more accurate way. In other words, the sound quality will be improved.

Materials that do not benefit from DCT

Most materials appear to benefit from deep cryogenic treatment because the treatment changes the molecular structure of the material from one in which is irregular due to uneven cooling occurring during manufacture. Wood, for example is organic and no improvement in any if its properties is achieved by DCT.

Materials that are damaged by DCT

If the deep cryogenic treatment is carried out under carefully controlled conditions there are very few materials that can be damaged. One substance that does not react well to cryogenic processing is glue. As most loudspeaker drive units use glue in their assembly, the cryogenic processing of loudspeaker drive units cannot be recommended.

Deep Cryogenic Treatment processes applied to Black Rhodium Cables and Connectors

DCT++. The DCT process described above is applied. Before the object is removed when ambient temperature is reached, it is subjected to a normal tempering re-heat. This re-heat cannot be applied to any cables containing parts (such as many types of plastic)that might be damaged by the re-heat. In practice the re-heat is fine for all bare wires, and for wires insulated in certain high temperature insulation such as PTFE and silicone rubber. Very careful control is needed for wires plated in tin due to the low melting point of tin.

Crystal Sound Process. The process known as ‘Crystal Sound Technology’ is a proprietary technique developed by Black Rhodium’s cryogenic process supplier, Frozen Solid based on its empirical tests.

Because a continuous conductor will offer lower resistance than one with a mechanical discontinuity, electron flow is more regular. The result is that sonic distortion in the music signal flowing through the wire caused by conductor discontinuities will be reduced.

The Benefits to Audio Cables of Deep Cryogenic Treatment

Unlike most other improvements in audio, Deep Cryogenic Treatment does not change the character of the sound, but it does make the listening to music a much more pleasant experience. Each aspect of audio performance is improved by a small but audible amount. Whilst an analytical assessment might consider these improvements to be small, the sum total effect on overall listening pleasure is much more dramatic.

At Black Rhodium we find the best way to describe the benefits of DCT to audio cables as:

A very small change in the sound of each cable

A very large change in the enjoyment of music.

Many people have written about the improvements to their sound quality by DCT. Here is a list based on our own experience and on comments seen on the web.

  • Expanded dynamic range
  • Improved transient response
  • Greater sense of ease
  • Clearer and more refined higher frequencies
  • More articulate bass
  • Sharper stereo images
  • Lower noise floor
  • Quieter and blacker background
  • Less distortion in vocal
  • Deeper and more open soundstage
  • Enhanced detail and definition
  • Greater separation of musical textures

The benefits to Audio of Crystal Sound Processing

Our experience of the Crystal Sound Process is that whilst the DCT process improves almost all aspects of the sound in almost equal ways, the Crystal Sound Technology changes the sound in a way that can only be satisfactorily described by saying that the Crystal Sound Process delivers a more full-bodied and more natural sound to the music that once heard you will not wish to take away.

Other Audio Products that benefit from DCT

Compact Discs

Stresses induced from the CD’s manufacturing process causes birefringence when the player’s laser tries to read the disk, degrading sound quality. A precisely controlled, deep cryogenic process stress-relieves the polycarbonate disk, making it more optically clear. This greatly reduces birefringence and improves audio quality.

Valves

The sound quality of thermionic valves is also improved with DCT.

Summary

Deep Treatment of audio cables is an essential ingredient of high quality audio cable design that cannot be ignored.

March 15, 2018

Posted In: Uncategorized

Audio distortion due to the Proximity Effect

Audio distortion due to the Proximity Effect

The Proximity Effect

When a wire carries an alternating current, such as may be carried on audio cables, it creates an associated alternating magnetic field around it. The alternating magnetic field induces eddy currents in adjacent conductors.

If there is an electric current flowing in an adjacent conductor, the eddy current caused by the first cable alters the overall distribution of current flowing through the adjacent conductor. The eddy current will reinforce the main current on the side facing away from the first wire, and oppose the main current on the side facing the first wire

This is called the Proximity Effect.

If two conductors have the same direction of their current, then the current in the wires is concentrated in the areas of the conductor furthest away from the other conductor.

Conversely if, as is the case with loudspeaker cables and power cables, the current in each conductor is flowing in opposite directions, the current in the wires is concentrated in the sides closest to the other conductor.

 

The proximity effect can significantly increase the resistance to alternating current of an adjacent conductor compared to its resistance to DC current. This effect increases with frequency.How the Proximity effect causes audio distortion

Most loudspeakers are complex reactive loads and, as a result, the voltage in either wire at any time is not in phase with the current.

The result is that the magnetic field that is altering the resistance of the wires is not in phase with the voltage in the wires at any time.

Put another way the current in one wire is modulating the output of the other wire at a level that has no relationship (at any point in time) with the voltage in the wire. Because of the phase difference the small change of the voltage to the loudspeakers due to the ‘proximity Effect’ is heard as random noise unrelated to the signal. This form of distortion is highly noticeable.

As an example of this effect, it has on occasions been claimed by loudspeaker designers that their new speaker is more ‘musical’ because the crossover has less components. It is possible that they may be saying that “because their loudspeakers have less components, there is less difference in phase between the current and voltage in the speaker cable and hence the ‘Transient Phase Distortion’ in the speaker is reduced.”

The Proximity Effect decreases as the distance between the two conductors increases.

Cable with thin insulation. The horizontal line shows the level of the magnetic field at the centre of the other conductor. Cable with thick insulation. By using thicker insulation the magnetic field at the centre of the second core is much reduced. This results in a lower level of ‘Proximity Effect’ audio distortion.

 

As the diagram above shows, increasing the separation between conductors by thicker insulation reduces the magnetic field strength that the current in each conductor causes in the other conductor.

Reducing the magnetic field strength reduces the audible distortion caused by the magnetic fields.

A typical speaker cable (left) with insulation thickness of 0.6mm alongside Black Rhodium Twist which has a 1.2mm insulation thickness. Both cables have the same 24 x 0.2mm diameter conductors

The pictures above demonstrate how cables can be built with thicker insulation. In practice, loudspeaker cables with thicker insulation, such as Black Rhodium Twist, Twirl and Samba, have proved this point by their extensive awards for the sound quality.

March 15, 2018

Posted In: Uncategorized