You may be familiar with the 5692 tube. Known for their build quality to withstand mutliple g's and to win the cold war. The engineer designing this tube was thinking about intercontinental ballistic missles, not the best tube for audio. But we benefit from the arms race. Back then this tube cost almost ten times as much as a typical 6SN7, and are very rare. Smooth mids, slightly relaxed highs. Wonderful for taming an overly energetic system... or for folks who just love that velvety smooth, 5692 sound.
Very highly sought after 6SN7 variant. These test perfect and are "da bomb" as the kids say. They were made by G.E., RCA, and CBS. This is the CBS, my personal fav. CBS 5692 throw the deepest soundstage of any 5692 in my experience.
They are easy to identify by the extra support rods and extra mica spacer. No other tube was built like the legendary 5692.
The tubes are marked as 6SN7 Zalytron. Zalytron was a tube re-seller, not a manufacturer.
Platinum grade - The best of the best. Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.
Gold grade - Low noise and microphonics with a triode balance typically between 15% and 20%, but may be higher depending on available stock.
Logo quality may vary from picture above. Price includes matching in any quantity you need at no extra charge.