Serial Numbers: 3A 02579 & 3A 02582. Production Year: 1967 (First Year). Condition: All original, never serviced, grilles never removed. Cabinets: Nice condition, a little work could make them excellent. ? WHY THIS PAIR IS EXCEPTIONAL. Serial numbers 3A 02579 and 3A 02582 place these speakers among the earliest AR-3a’s ever produced – from the very first year of production (1967) – and only 3 digits apart, confirming they left the factory virtually back-to-back as a true matched pair. The switch from the desirable alnico-magnet woofers to ceramic woofers didn’t occur until serial numbers in the high 28,000s (late 1969). These speakers, at 02579/02582, almost certainly retain their original alnico woofers with cloth surrounds – the most sought-after configuration among AR-3a collectors and enthusiasts. PROVENANCE & CONDITION. Grilles have NEVER been removed – completely unmolested. Never serviced, recapped, refoamed, or modified in any way. All drivers original and fully functional – they sound great. Cabinet conditions are nice, could use a little TLC. This is not a restored pair. This is not a “good for its age” pair. This is the real thing – a time capsule. ? ABOUT THE AR-3a. The Acoustic Research AR-3a U. Patent 3,033,945 is widely regarded as one of the most historically important loudspeakers ever manufactured. Introduced in 1967 by Acoustic Research of Cambridge, Massachusetts, it pioneered the acoustic suspension design and set the standard for high-fidelity speaker reproduction for a generation. It was the reference standard in studios, universities, and audiophile listening rooms worldwide. Located in Sioux City, Iowa. I’m happy to provide additional photos, serial number close-ups, or answer any questions. Serious buyers only please – this is a firm price reflecting the exceptional rarity and condition of this pair.