The Black Rhodium Blog

Basso Profundo - a Sub Woofer Cable for Very Deep Bass

By Graham Nalty, proprietor of Black Rhodium

Black Rhodium Basso Profundo Deep Bass Sub-Woofer cable is designed to deliver the very best low frequency sound from High End Sub Woofers.


The design of Basso Profundo Deep Bass Sub-Woofer cable 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 bass notes with precision and power.


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 Basso Profundo Deep Bass Sub-Woofer cable we have taken great care to minimise each and every type of distortion separately by careful design and very extensive experimentation and audition.


The design features of Basso Profundo Deep Bass Sub-Woofer cable are based on applying the very best features from both the Charleston loudspeaker cable and the Chorale S RCA stereo interconnect to create a capable accurate resolution of low frequency notes. These features include proprietary innovations, based on extensive research and testing, exclusive to Black Rhodium. Other features of design are based on classical electrical engineering practice extensively used in audio and elsewhere.


  1. The conductor wire we use for the highly critical electrical signal that carries the low frequency music has been chosen by extensive audition over many years and our best choice without taking the extreme expense of using Precious Metals.
  2. Our conductor wire has very low impurities and is processed by a Deep Cryogenic Treatment to improve the molecular structure and enhance sound quality.
  3. Our conductor insulation has been tested by audition as our best solution and contains a high proportion of air. 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).
  4. To the best of our knowledge, none of the materials we use generate noise due to tribo-electric effects.
  5. Extensive tests and audition have ensured that our screening against picking up Radio Frequency Interference (RFI) is effective.
  6. Extensive tests and audition have ensured that our screening is highly effective against external magnetic fields.
  7. Basso Profundo Deep Bass Sub-Woofer cable 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.


Basso Profundo Deep Bass Sub-Woofer cable 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.