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Our Thoughts RADAR AI

Condition is unknown, but at US$695 this sits well below the recent used market’s US$1,185 25th percentile and far under the US$1,675 median, so it reads as a strong deal rather than a merely fair one. For a Threshold preamp, that’s the kind of number that should get a serious buyer’s attention.

Threshold gear is well regarded for a clean, refined, high-current presentation and real long-term audiophile credibility, so the upside here is getting serious performance at a deep discount. With condition not stated, the main thing to verify is basic functionality, service history, and whether it has the original power supply, remote, or any add-ons that affect value; at this price, even a modestly incomplete example can still make sense if it’s electrically healthy.

Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.

About Threshold

Threshold Audio emerged in Sacramento, California, in 1974, founded by renowned audio engineer Nelson Pass alongside graphic designer René Besne and Joe Sammut. Pass, a pioneer in amplifier design, launched the brand with the groundbreaking Threshold 800A power amplifier in 1975, introducing a novel sliding bias system that boosted Class A efficiency while employing 48 output transistors in a sophisticated triple-series/triple-parallel configuration. This California-rooted heritage defined Threshold as an innovator during its original run, which spanned until the mid-1990s, after which the intellectual property changed hands, including a 1994 acquisition by investor Randy Patton, who integrated it with PS Audio and relocated operations to Camarillo.

The brand focused squarely on high-end amplification, producing iconic power amplifiers like the 400A and 800A, the Stasis series renowned for their balanced Class A performance, and preamplifiers such as the NS10, SL10, and FET range including the FET-1, FET-2, FET-9, and FET-10. Later designs, like the T-200 by engineer Michael Bladelius, continued this legacy. Threshold eschewed speakers, turntables, DACs, headphones, or cables, concentrating instead on pure analog amplification that prioritized sonic purity and robustness.

Threshold holds a revered position as a vintage high-end icon, cherished by collectors and audiophiles for its enduring sound quality and Pass's technical wizardry. Once a market leader in premium solid-state gear from 1975 to 1992, it remains a sought-after name in the used market, embodying boutique excellence rather than mass production, with modern revivals under Threshold Audio sustaining its elite reputation.

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