In 1982 Sony gave us "Perfect sound forever," along with the attitude that, "it's just digital, so all CD players sound the same." That was disproved and qualitative differences between players became accepted truth. Next came separate transport and DAC combos, which brought with it the attitude that "all S/PDIF digital audio cables sound the same..." until that too became disproved. Now the frontier has moved once again. Is digital audio really just ones and zeros? We don't believe so, and once you've had a chance to listen to Pearl USB, you won't think so either... SOLID LONG-GRAIN COPPER (LGC) CONDUCTORS: Solid conductors eliminate strand-interaction distortion. Pearl's solid Long-Grain Copper allows a smoother and clearer sound than cables using regular OFHC (Oxygen-Free High-Conductivity) copper. OFHC is a general metal industry specification regarding "loss" without any concern for distortion. LGC has fewer oxides within the conducting material, less impurities, less grain boundaries, and definitively better performance. FOAMED-POLYETHYLENE INSULATION: Any solid material adjacent to a conductor is actually part of an imperfect circuit. Wire insulation and circuit board materials all absorb energy (loss). Some of this energy is stored and then released as distortion. Pearl USB uses air-filled Foamed-Polyethylene Insulation because air absorbs next to no energy and Polyethylene is low-loss and has a benign distortion profile. Thanks to all the air in Foamed-PE, it causes much less of the out-of-focus effect common to other materials. TERMINATIONS: Precision gold-plated plugs are carefully attached with the very best solder. Through choice of flux and metallurgy, AQ solder has been optimized to make a low-distortion connection. The difference you hear between solders is a result of connection quality. AQ solder does not have a high silver content because the more silver there is in solder, the more difficult it is to make a good connection.