Frequently Asked Questions

Questions:

• What is the directionality of your cables?
• I have a stereo pair of Purist cables, which is the right channel, and which is the left?
• Why are there are four cables in my set of speaker cables?
• What are the differences between Fluid, Ferox, and Contego?
• How long does it take to break-in a cable?
• How does Purist Audio Design measure their cables?
• What is EMI ?
• What is RFI ?
• How does EMI/RFI enter in and affect a system?
• Why is there such a long lead on the AC/M end of the Purist Limited Edition?

Answers:

What is the directionality of your cables?

Interconnects (Including Digital and Phono): The end of the cable that is labeled is the Source End (Input End).
Speaker Cables: The end of the cable that is labeled is the Amp End (Input End).
Power Cords: The end of the cable that is labeled is the end that will plug into the power source.

I have a stereo pair of Purist cables, which is the right channel, and which is the left?

Vesta RCA Interconnects: There are red or white bands on each RCA barrel. The white banded barrels signify Left Channel, and the red banded barrels signify Right Channel.
Vesta Balanced Interconnects: There is no specific designation, simply select one of the two to use for the Left Channel, and use the second for the Right Channel.

Musaeus, Elementa Advance, Venustas, Proteus Provectus, and Dominus Interconnects: Each cable in the set has either red or blue heat shrink on each connector. The cable with blue heat shrink signifies the Left Channel, and the cable with the red heat shrink signifies the Right Channel.

Aqueous Anniversary and Purist Anniversary Interconnects: Each cable in the set has either red or black heat shrink on each connector. The cable with black heat shrink signifies the Left Channel, and the cable with the red heat shrink signifies the Right Channel.

All Speaker Cables: There is no specific designation, simply select one of the two to use for the Left Channel, and use the second for the Right Channel.

Why are there are four cables in my set of speaker cables?

The Proteus Provectus, Dominus, and Purist Anniversary Speaker cables are each four cable sets. Although there are four cables, it is still two-channel. We separated the positive and negative signals for each channel into a separate cable. One red lead cable and one black lead cable make up a channel.

What are the differences between Fluid, Ferox, and Contego?

The table below give a general break-down of the basic differences.

How long does it take to break-in a cable?

All Purist Audio Design Cables usually take a minimum of 100 hours of burn in. Please check the Products Page for detailed specifications on each of our products. The break-in time can also be significantly reduced by using our System Enhancer Ultimate.

How does Purist Audio Design measure their cables?

The Purist Audio Design Interconnects and Digital Interconnects are measured as shown in the diagram below:

The Purist Audio Design Phono Interconnects and Phono Din are measured as shown in the diagrams below:

The Purist Audio Design Speaker Cables are measured as shown in the diagram below:

The Purist Audio Design Power Cords are measured as shown in the diagram below:

What is EMI?

Electromagnetic interference or EMI is the undesirable electromagnetic emission produced by any electrical disturbances of either man-made or natural occurrences. This interference is often the leading cause for undesirable responses, disruption and/or degradation in the performance of electrical equipment, including many of the electrical components in a typical audio/video system. Electromagnetic interference can propagate and couple itself directly through conduction onto signal and power conductors. It also propagates via radiation through free space and couples itself through induction or capacitive coupling onto signal and power conductors, or even through the metal chassis of electronic equipment and the inherent electrical components.

What is RFI?

Radio frequency interference or RFI is the more specific electrical interference associated with communication transmission frequency bands ranging from well below 100kHz, to well above 30GHz..

How does EMI/RFI enter in and affect a system?

EMI/RFI interference usually enters a system at various weak points within an audio/video system. It can be inductively introduced into a poorly shielded enclosure and continues to the electronic circuitry. It can be directly coupled through improper ground implementation. It can enter at the various power entry points of an audio/video system. Additionally, if not properly filtered and decoupled, power supplies can often pass on EMI/RFI noise from the incoming AC source to the outputted DC.

However, the most common source of EMI/RFI noise is through the system cabling via direct, inductive and/or capacitive coupling. The noise interference here tends to reduce the overall noise floor, decreases the signal-to-noise ratio, clouds and smears the micro-dynamics, and causes signal distortion from destructive interference. In many situations, when poor construction, inadequate shielding, and/or misapplication are factors, system cabling can act as prefect antennas and transmission medians for EMI/RFI noise throughout the system. In many case studies, when trying to isolate noise issues within system cabling, it has been found that power cables, in general, tend to be the strongest source and leading culprit to direct coupling of EMI/RFI noise, since the electrical networks they connect to are significantly polluted by noise.

For Audiophiles, these disturbances tend to wreak havoc and lead to a prevailing erosion in the quest to reach sonic purity, partly due to the ease at which this interface is coupled within an audio/video system. The most commonly observed nuisances include the type of interference that is either directly or indirectly coupled somewhere hidden within the component chain of the system and is often heard in the form of hum and/or a high pitch whine/static at the speakers. The problems that are heard in the form of, poor focus and separation in musical instruments and voices, muddy bass, and an attenuated and compressed sound of the high components, can be attributed to EMI/RFI as an influential part on induced jitter in the digital play-back source or by noise coupling to an analog signal, thereby reducing the overall noise floor and signal to noise radio (SNR).

Other effects of EMI/RFI that are often overlooked are coupled noise interferences that induce instability, in feedback base amplification, and/or other signal processing type circuitry. Even though, most feedback network topologies are designed to minimize instability and to maintain linearity in performance. Due to the characteristics of the circuit topology and to the small parasitic capacitance that exists within solid-state devices and circuit boards, these circuits can suffer from performance and efficiency losses, when subjected to high-frequency noise interference. At high frequencies, the phase relationship of the input/output voltage/current will shift enough leading to potential instability, and is often compounded or worsened by the coupled high frequency noise components of EMI/RFI onto the analog signal (specifically RFI). The instability then leads to loss of performance, loss in efficiency, generation of excess heat, and the creation of additional unwanted noise. This is interpreted by the listener as severe sonic degradation and limiting dynamic performance.

Why is there such a long lead on the AC/M end of the Purist Limited Edition?

We designed the Purist Limited Edition Power Cord with a 60.0 cm (23.6") flex lead on the AC/M end to allow the cable to be plugged into a standard height outlet and have the filter housing to rest on the ground. Thus eliminating undo stress on the connector. This means when ordering a 1.0 M Purist Limited Edition Power Cord, the cable will actually measure 1.8 M (60.0 cm for the AC/M flex lead, 100.0 cm for the body, and 20.0 cm for the IECC flex lead).

Purist Limited Edition Power Cord