1 Pair of the AQ Tree Series Oak speaker cables in excellent condition. Recently outfitted by AudioQuest with brand new U Spades on each end. 7 feet long from spade to spade. MSRP $3000 pr AQ Tree Series Speaker Cables - OakSOLID PERFECT-SURFACECOPPER+ (PSC+) CONDUCTORSSolid conductors preventboth electrical and magnetic interaction strand-to-strand interaction, majorsources of distortion. Surface quality is critical because a conductor can beconsidered as a rail-guide for both the fields within a conductor, and for themagnetic fields that extend outside the conductor. The astonishingly smooth andpure surface of all AudioQuests’s Perfect-Surface metals nearly eliminatesharshness and greatly increases clarity compared to lesser materials. Extremelyhigh-purity Perfect-Surface Copper+ further minimizes distortion caused bygrain boundaries, which exist within any metal conductor, nearly eliminatingharshness and greatly increasing clarity compared to OFHC, OCC, 8N and othercoppers.MULTI-LAYER CARBON-BASEDNOISE- AND CROSSTALK-DISSIPATION SYSTEMThis cable’s negativeconductors are covered with partially conductive Carbon-Loaded Polyethylene.This remarkable material reduces radio-frequency garbage being fed back intothe amplifier. The sonic benefit is exactly the same reduction in “hash” and improveddimensionality that comes whenever RF interference is reduced in an audiocircuit. In addition, a carbon layer damps interaction between positive andnegative conductors, and an external Carbon-Based NDS System reduces externalinterference.DOUBLE COUNTER-SPIRALGEOMETRYAll AQ “Tree” Seriescables have an inner circular array of positive conductors spiraling in onedirection, around which the negative conductors spiral in the oppositedirection. This makes possible the significant performance advantage of havingthe positive and negative conductors cross each other instead of beingparallel. The critical need for positive and negative to have a fixednon-changing relationship is ensured as the negative and positive groups are infact two tubes with a perfectly consistent relationship. The result is anastonishing clarity, like focusing a camera lens you had no idea was so far outof focus.FOAMED-POLYETHYLENEINSULATION (FOR ALL POSITIVE CONDUCTORS)Any solid materialadjacent to a conductor is actually part of an imperfect circuit. Wireinsulation and circuit board materials all absorb energy. Some of this energyis stored and then released as distortion. This cable, however, uses air-filledFoamed-Polyethylene Insulation on both conductors. Because air absorbs next tono energy and Polyethylene is low-loss and has a benign distortion profile,Foamed-PE, with its high air content, causes much less of the out-of-focuseffect common to other materials.DIELECTRIC-BIAS SYSTEMWITH RADIO FREQUENCY TRAPAll insulation between twoor more conductors is also a dielectric whose properties will affect theintegrity of the signal. When the dielectric is unbiased,dielectric-involvement (absorption and non-linear release of energy) causesdifferent amounts of time delay (phase shift) for different frequencies andenergy levels, which is a real problem for very time-sensitive multi-octaveaudio. The inclusion of an RF Trap (developed for AudioQuest’s Niagara Series of power products) ensures that radio-frequency noise will not be induced intothe signal conductors from the DBS field elements. (DBS, US Pat #s 7,126,055& 7,872,195)