The Black Rhodium Blog

How the Laws of Physics influenced the design of our Chorale S

Black Rhodium Chorale S RCA stereo interconnect is high performance cable designed to deliver the maximum musical information in use.


Here is some of the history of its design, production and launch


The design of Chorale S RCA is based on a very thorough understanding of the Laws of Physics and the effects they describe. Black Rhodium has developed several effective engineering solutions that minimise the effects that the Laws of Physics describe to produce a cable that plays music beautifully through any audio system.


The seven Laws of Physics that are known to influence sound quality in a cable that carries an electrical signal representing music can be listed as;

  1. Different conductor wires sound different. Our experience shows us that the best, most accurate, sounds are heard when using the most expensive materials.
  2. Impurities in the metal and irregular molecular structure in the drawn wire result is a less clear sound.
  3. Dielectric absorption, in which the insulation can receive electrical charge from the voltage in the wire and return it back a short time interval later creates a time- smeared distortion of the sound.
  4. Tribo-electric effects in which friction between screen and insulation generates electrical charges that add noise.
  5. All electrical wires can act as radio aerials and pick up high frequency noise. This noise can modulate the audio frequencies of the music to change and distort the music
  6. External magnetic fields can change the current flow in a wire that creates a further source of distortion to music. These fields can be created externally or also by adjacent conductors in the cable.
  7. Electrical forces due to voltage differences between conductors create mechanical forces that cause micro-vibrations within the cable. These micro-vibrations alter the electrical characteristics between the conductors causing a noise voltage that modulates and distorts the music signal.


In the design of Chorale S RCA we have taken great care to minimise each and every type of distortion separately by careful design and very extensive experimentation and audition.


Many of the design features of Chorale S RCA are based on proprietary innovations, based on extensive research and testing, exclusive to Black Rhodium and cannot be revealed in detail. Other features of design are based on classical electrical engineering practice extensively used in electrical engineering.


How we designed Chorale S RCA


Conductor wires


The conductor wire in a cable carries the highly sensitive electrical signal that produces the music through your loudspeakers of headphones.  The better the (sound) quality of the wire, the better the overall quality of sound in the cables and enjoyment of music played.


Over the years, Black Rhodium designer Graham Nalty has auditioned many different wires to learn how they affect sound quality. Whilst Precious Metals, such as palladium, platinum and Rhodium give the very best quality sound we have heard, they are simply too expensive.


We have used silver wire a great deal in our cables. This gives a very clear and clean sound, but silver is more difficult to get the last ounce of clarity when a large choir sings powerful high notes. In the end we have returned to a wire we have used before and we find superior to silver but a lot less expensive than the palladium wire we use in Cantata.


Deep Cryogenic Treatment


Our conductor wires are processed by a Deep Cryogenic Treatment that re-arranges the molecules in the wire in a way that produces a cleaner and more natural sound.


Wire Direction


We have conducted many tests on the direction of wires when used for audio. We have found that when both wires in a stereo cable are cut from the reel to run in the same direction they sound slightly clearer and give the impression of a quieter background behind the music. We take great care to see that all wires we remove from reels is marked for direction before we use them.


Dielectric Absorption


Dielectric Absorption, in which electrical energy from a wire transfers to charge the insulation electrically and returns to the wire after a short interval of time, causes time smearing distortion that reduces clarity in the music. In Chorale S RCA we use a low mass insulation combined with air to reduce the dielectric absorption to audibly less than using the any of the more common insulating materials.


Radio Frequency Interference and Electromagnetic fields.


We have tested many different materials and techniques for screening. We have developed a highly effective screen that very substantially removes almost all distortion caused by RFI and EM I.


Micro-vibrations caused by electric field forces.


Chorale S RCA is vibration damped along its length by an effective damping material that has proved highly effective in the past. Additional its outer braid provides additional damping against external vibrations.


Design of Chorale S RCA stereo interconnect


Palladium wire has been chosen by extensive audition over many years and our best choice without taking the extreme expense of using Precious Metals.

  1. Our conductor wire has very low impurities and is processed by a Deep Cryogenic Treatment to improve the molecular structure and enhance sound quality. We apply careful quality control of the wire direction during construction to ensure a quiet background to the music. (For more information, please read our Technical Note cable direction).
  2. Our conductor insulation has been tested by audition as our best solution and contains a high proportion of air.
  3. To the best of our knowledge, none of the materials we use generate noise due to tribo-electric effects.
  4. Extensive tests and audition have ensured that our screening against picking up Radio Frequency Interference (RFI) is effective.
  5. Extensive tests and audition have ensured that our screening is highly effective against external magnetic fields.
  6. Chorale S RCA is fully damped against micro-vibrations within the cable along its full length. Its attractive external braid is also highly effective at reducing transmission of external vibration to the cable.


Chorale S RCA is fitted with Graham Nalty Straight Line Contact GN4 RCA plugs. The Straight Line Contact between the return conductor and socket has been chosen from listening tests that showed straight Line Contact connectors can deliver a large uplift in sound quality compared to high quality connectors with a circumferential connection of the return conductor.

The GN4 plugs are plated in rhodium. In listening tests, rhodium plated connectors give a cleaner sound that can add excitement to the presentation of the music.


Further information on the Graham Nalty GN4 Straight Line Contact RCA plugs can be seen in: