RAAL Requisite is a new undertaking for the venerable maker of true ribbons. Such a quickness to the sound, immediate stops and starts, tremendous dynamic swings with macro punch and a fall back to micro detail. These are designed for mixing and mastering and would make a great uber-'phones for home use. Daft Punk "Get Lucky" never sounded so good, tip top highs to subterranean lows. The SRH-1A (Studio Reference Headphone), sells for $3500 and comes carrying case, all cables and amplifier interface. Field replaceable ribbons pop easily in and out and are $50.