• Evidence Audio Design Philosophy:

• But Why?

Expressing emotion, from beauty and delicacy to anger and force is the raison d'être for music.
   
Hardware is the collection of tools an artist uses to best express his or her emotion.
   
While a great deal of work has been done with varying approaches to cable design on the playback side of music production, few designers have made available valid cable products for getting your message across to an audience or recording device.
   
Evidence Audio™ introduces cables designed to let you communicate your heart and soul as it is meant to be heard.

• A Budget

A careful balance of long-term experience, both subjective and objective, has shown there are a few key components that are responsible for the degradation of a delicate audio signal as it passes through a cable.
   
Cables from Evidence overcome these distortions by following a simple set of rules for a given price.
   
The Lyric HG™ and The Melody™, use the ultimate blend of materials and geometry for a given budget. The result are cables we feel are far superior than those costing many times the price.
   
Rather than apply a seemingly arbitrary price based on marketing expectations, Evidence Audio produces the best possible product for the money. Given a higher or lower budget, alternative compromises in material or geometry can be engaged (or avoided) to achieve the best possible performance for your dollar.

• Materials Matter

An audio signal must pass a minefield on its way to an output device. Everything that comes in contact with the signal has an effect - sometimes desired, but very often not.
   
No component in your set-up can improve the quality of your audio signal (outside of some Digital Signal Processing tools fixing serious problems). There is no cable, stomp-box, or pre amplifier that can make your music sound "better;" they can only make your music sound "less worse," than if played through a product built with inferior components.
   
This discussion is separate from delivering a clean versus a grunge sound. Tools should be chosen to express your feeling whatever it may be. However, "tone-agnostic" devices such as cables should not impart their own sound. Cables should be designed to deliver whatever recipe you've cooked up without changing or hiding any of the flavors. An analogy would be a cup for your coffee. If you care about the punch, subtleties and complexities in a cup of Joe, you take time using the right tools and beans to deliver an experience. It makes no sense to drink your crafted brew from a styrofoam, plastic or paper cup as each material hides or changes the flavor of what you've created. Adjustments can be made for using a particular type of cup on a regular basis, but if you change your blend, do you want to find a different cup to use each time? The cup should be neutral. You need to use it, but it should do its job in such a way that whatever you pass through it, it doesn't degrade the brew.
   
Cables degrade an audio signal by using inferior conducting material, insulation material, plugs, solder, strand design and geometry.
   
The Lyric HG and The Melody from Evidence Audio incorporate the following features to overcome distortions caused by other cables:

• High-grade IGL™ Copper conductors

Copper is a wonderful conducting material, yet not all copper sounds the same.
   
High purity copper used in audio cables range in level from "tough-pitch" to "7N." These types of copper vary in the number of impurities as a percentage of copper, as well as the number of copper grains per foot.
   
A 20-foot guitar cable using typical high purity copper (tough pitch) will have approximately 30,000 grain boundaries. Impurities such as sulfur, iron and gold collect between these grains of copper. As the signal crosses these grain boundaries, the effect on the sound at your ear is an additional "bite" or "edge" in the mid-to-high frequency range.
   
At the other end of the spectrum is "7N" copper, which stands for having seven nines in purity value, i.e. being 99.99999% pure. This copper has far fewer grain boundaries and certainly fewer impurities between those grains, and you can hear the benefit of this fact. Distortions caused by the audio signal passing grain boundaries are irritating and mask subtleties such as the harmonics of your tone. It takes serious equipment to refine copper to such levels of purity. Sumitomo™, Dowa™and Nippon Mining™ in Japan are among the few companies in the world with such equipment. Given that there is no market for such material outside of specialty audio and video cable products, the costs for such material is very high.
   
Between the commonly found high purity copper and the good-but-pricey stuff, lies a range of copper for a cable designer to choose from. The coppers available range is in terms grains per foot, purity level, price and of course sound quality. Years of listening tests have led us to work with a particular copper (with approximately 400 grains per foot for those counting) that sounds close to 7N copper in terms of dynamics and clarity, yet costs far less.

A note on silver: Silver is a wonderful conductor, but subjective differences in the silver available to cable manufacturers are often greater than the differences between copper. Solid silver conductors can be virtually transparent, but listen closely as poorly drawn silver can sound worse than bad copper.

One material to listen to, that will give a great education on the effect of materials on sound, is silver-plated copper. The discontinuity between the copper and silver, as well as the impurities that collect between these layers, are exactly where high frequencies are carried with great density. The effect is one that will have you reaching for ear plugs after short use -- or make you wish you played Bass instead.

• Solid Core Conductors

Another source of distortion in cables is strand interaction. Cables are stranded to provide flexibility. However, every strand in a bundle is trying to carry the same audio signal as the strands next to it. The problem arises given the fact that current running through any single strand sets up a magnetic field. This magnetic field introduces change to the signal carried in neighboring strands. The more strands a conductor has, the worse the problem. When compared with a solid conductor of equal cross-sectional area, a stranded conductor obscures micro-dynamics and adds an edge to the sound similar to the distortion caused by low-purity copper. In addition, mid-bass and lower frequencies lose their sense of impact and articulation. Bass lines with stranded conductors are "fat" and slow, with obscured harmonics in comparison to bass conducted through a solid core cable.
   
Cables from Evidence Audio used solid core conductors and give up some of the flexibility of a stranded cable. However, we think you'll appreciate the results in your listening, and find the cables still flexible enough to use on stage

• Conductor Size

The phenomenon of skin effect causes high frequencies and low frequencies to be carried with different current densities relative to a position on the conductor - notably the outside skin of a conductor. While there are various formulae and theories as to how skin effect applies (or doesn't) to the audio spectrum in cables, empirical listening tests have shown clear differences in conductors of different size (all else being equal). Once a conductor is larger than 18awg, high frequencies tend to lose their sense of "air" or ambience.

When overcoming resistance in speaker level applications requires the use of a conductor larger than 18awg, the only acceptable solution is to use several 18awg or smaller conductors separately insulated from each other to avoid strand interaction.

• Symmetrical Design

Audio is alternating current, hence it passes through the negative conductor at the same time as the positive one. A common way for cable manufacturers to reduce their cost, is to use the shield as a conductor. Shields are important for keeping interference out of the conductors, but they don't conform to the requirement of a good audio conductor by being solid, as well as symmetrical with the positive conductor.

Evidence Audio uses identical conductors for positive and negative signal paths. The shield is only attached at the receiving end and carries what it is supposed to - the noise.

• Insulation Material

Now that we've got the audio signal on the right path, it's important to consider that a great deal of the signal uses the conductor as a wave-guide and travels on the edge and outside of the conductor as a magnetic field. The ideal insulator would be to have none, yet this is impractical for obvious reasons. Instead, a material must be chosen that causes minimal change to the signal as it passes through it.
   
The Lyric uses a foamed polyethylene insulating material maximizing the amount of air around the conductors. This offers excellent value compared to Teflon™ insulation, which sounds good but can cost more than the conductors themselves; and PVC with its poor dielectric characteristics that can rob the sound of coherence and dynamics.

• Geometry

How the conductors are run end-to-end relative to each other and the shield will yield a capacitance value for a cable.

Generally speaking, conductors which run parallel will yield a cable with high inductance and low capacitance. A cable with braided conductors will have low inductance and high capacitance.

The Lyric is engineered to have very low capacitance, and can be used in long lengths without any high frequency roll-off.

• Shielding

Now that we have a signal path to minimize distortions caused by the cable itself, it is important to protect the signal from external noise with a proper shield.

The Lyric uses an extremely high-density pure copper braid to keep out interference -- in addition, the conductors are wrapped with graphite tape to reduce triboelectric noise (mechanically induced noises which occur from moving the cable or tapping on it).

• Plugs

Neutrik™ manufactures the plugs used on the Lyric. The base metal used is sonically benign, and the nickel plating does a good job of protecting against corrosion. While gold plating has a higher perceived value than nickel plating, gold offers no conductive advantage to nickel in this context and is not worth the additional cost.