Distortion: ours vs. theirs

Why high-frequency extension, capacitance and picofarads go hand in hand regarding: “How much of the music do you really hear?”

More capacitance = more distortion

HF extension, or “high-frequency extension,” can be described as the frequencies and harmonic structure heard at the sonically extreme levels in music. Part of the frequency/harmonic structure is not even heard but felt in music, through the inner ear bones, the face, the skull and so on. The sonic benefits apply not only to cymbals, triangles and brass instruments but also to violins, which produce frequencies as high as 40 kHz. The high-frequency extension is needed in order to have a more authentic harmonic structure, which enables us to hear leading-edge transients and the decay of musical notes. Otherwise, the leading-edge details of midrange and bass notes sound dulled. This is also measurable with square waves, where high-frequency attenuation of ultrasonic and audio band frequencies causes distortion known as overshoot and ringing of the square wave.

Part of the reason that TARA Labs interconnects offer the listener more high-frequency extension than any other cables in the world has to do with our extremely low capacitance (measured in picofarads, or pF). This remarkable level of achievement has been accomplished through our 40 years of experience in technology & design. Even though this technology exists in all our interconnects, our flagship Grand Master Evolution interconnects offer a clear example of just how far we have taken this technology. While virtually all of the cable manufacturers in the world claim capacitance in the double digits, TARA Labs Grand Master Evolution interconnects have a remarkable capacitance of 2.0 pF. This translates to what Stereophile’s top reviewer, Michael Fremer, called “limitless high-frequency extension” in his review of the Evolution cables.

To explain the importance of this technology in more detail: for every doubling of the capacitance, the high-frequency bandwidth is reduced by a full octave. High-end audio interconnects from the most well-known and respected audio cable manufacturers, such as Nordost, Cardas, Stealth, Crystal, Transparent, MIT and Kimber, have capacitance numbers that are typically in the low double digits, or slightly lower than 10 pF in their extreme top-of-the-line audio cables. In layman’s terms, more capacitance equals more high-frequency roll-off and distortion. For example, if you take 4 pF, double it to 8, double it again to 16 and then double it again to 32, you have doubled the capacitance three times, and each doubling is an octave of high frequency lost. In this example, three full octaves of music have been lost or filtered away.

In this particular case, three full octaves of high-frequency extension are lost due to the increased capacitance. The result is more distortion, a higher noise floor and a loss of high-frequency extension, and the nuances of the music are lost at this extreme level of audio technology. Please note that the audible frequency spectrum ranges from 20 Hz to 20 kHz, the ultrasonic spectrum from 20 kHz to 100 kHz, and the RF (radio frequency) spectrum from 100 kHz to 300 GHz.

Due to the Grand Master Evolution’s ultra-low capacitance of 2 pF, the listener is able to hear more of the music faithfully reproduced than with any other high-end reference audio cables in the world.

Below is a list comparing the capacitance of TARA Labs interconnect audio cables, measured in picofarads (pF), with that of cables from some of the leading and most well-respected audio cable manufacturers in the world. Remember, more capacitance means more distortion.

Speaker cable capacitance and inductance

Regarding capacitance in speaker cables: signal voltage and current are much higher in speaker cables than in interconnects, and therefore play a more significant role in speaker cables.

So capacitance is not really a predominant factor when evaluating speaker cables, though TARA Labs does address it in its speaker cables by having physically separate “positive & negative” cable runs within each pair, which greatly reduces cable capacitance. The most important factor is speaker cable inductance, which is why TARA Labs offers its “SP” speaker cable models.

For more on inductance, see our high-end audio glossary.

NOTE: The cables in each comparison below are grouped by approximate retail price.