From the manufacturer:
Vintage-correct reproduction of 1950s Tele® rhythm pickup. Great for traditional country, country pop, surf, rockabilly, blues, and blues-rock.
The rhythm (neck) pickup in a well-balanced vintage Telecaster compliments the bright twang of the lead pickup with a smooth and open tone, warm lower-mids and airy highs. Comes with a chrome-plated brass cover and waxed cloth hookup cable.
Available in rhythm (neck) position only. Either the STL-1 or STL-1b is the most common match for the lead (bridge) position.
For all well-balanced instruments. Works equally well with maple and rosewood fingerboards.
Richard Young / Kentucky Headhunters, Doug Pettibone / Lucinda Williams, Nick Hoffman / Kenny Chesney, Adam Gaynor / Matchbox 20, Gilby Clarke / Guns ‘N Roses & Heart, Webb Wilder "
Best videos/sound clips:
Here is a great clip from Seymour Duncan Pickups demonstrating the STR-1 Vintage Tele Rhythm pickup. Skip to 0:56 to hear the STR-1 on a clean setting. The tone is very balanced with warm lower-mid tones and a very musical high-end. Each note has amazing definition, with great dynamic control and a natural snap. At 1:35 you can hear just how well the STR-1 works with a bit of overdrive, producing just the right amount of chime and sustain for screaming leads. For a smooth and versatile tone, the STR-1 is a great fit for all styles from country to rock, surf, rockabilly, and beyond.
This is a nice demo showing just how versatile the Seymour Duncan STR-1 can be. The pickup has a really nice low-end punch and sounds especially nice coupled with a time-based effect (delay, chorus, reverb) for a full deep sound, as heard in this clip at 0:11. Skip to 0:28 to hear the lead capabilities of this pickup, noting the airy upper harmonics and classic Tele snap. At 1:50 you can really hear how much sustain the STR-1 has on tap, not to mention its unsuspecting shred capabilities. The tone is extremely melodic and every note is really well articulated - especially when it comes to sweep arpeggios and other fast riffing at 2:40. Overall, the STR-1 is an extremely dynamic and versatile pickup with a very unique sound of its own.