6n6p by Foton with double support square getter and gold grid. Please not that one of the tubes has slight getter fading at top of the tube please see pictures. Tested on Amplitrex at1000 see pictures for full test results. I test all tubes I sell for noise on the Amplitrex and in my personal headphone amplifier.

foton 6n6p square getter rareIn the tube-rolling community, the 1960s Foton Tashkent 6N6P (6Н6П) with the "Square Getter" is widely considered the absolute "Holy Grail" variant of this specific Russian double triode. [1, 2]While standard 1970s or 1980s NEVZ-factory 6N6P tubes are cheap and plentiful (often selling for around $15–$25 a pair), a verified, matched NOS pair of 1960s Foton square-getters fetches between $225 and $350+ from high-end vintage sellers. [1, 2, 3, 4]Why is the Foton Square Getter Variant Rare?

• The Tashkent "Foton" Factory: Tubes manufactured at the Foton military plant in Tashkent during the mid-1960s feature exceptional structural quality control, rigorous military-grade "OTK" inspection stamping, and high-grade internal materials. [1]
• The Square/D-Getter Assembly: Sometime in the late 1960s, Soviet manufacturing shifted almost entirely to cheaper, more automated "halo", "disc", or "pan" getter rings. The older square/D-shaped metal getter frames require more meticulous hand-assembly and represent the peak era of Soviet vacuum tube production. [1]
• Gold Grid-Posts: These specific 1960s Foton tubes were built with gold-plated grid wires, which significantly stabilizes electrical parameters and dramatically reduces background noise and microphonics over time. [1, 2]
• Sonic ProfileEnthusiasts who track down these tubes describe a distinct sonic leap over standard production 6N6Ps:
• Blacker Backgrounds: The combination of strict military selection (OTK) and gold grid construction eliminates the typical background hiss or heater-to-cathode leakage hum plagued by bulk-grade variants. [1]

The square-getter Foton (Photon) 6N6P double triode from 1960s Tashkent (USSR) is often called a "Holy Grail" tube by audiophiles for a mix of vintage production era traits and subjective sound quality: [1, 2, 3, 4]

• 1960s Vintage & Build Quality: Early 1960s production from the Foton plant features distinct internal construction—such as boxier plates, specific weld points, and gold grids—that differ from later, more common Soviet versions (which typically use a saucer-shaped getter and standard plate designs). [1, 2]
• The Square Getter Marker: The square getter shape itself doesn't inherently change the physics of how a tube sounds; instead, it serves as a visual fingerprint or "flag" identifying a specific, high-reliability production run from that era and factory. [1]
• Audio Rolling Reputation: In headphone and pre-amp setups (such as Little Dot amplifiers), enthusiasts report that these early Foton square-getter tubes deliver a distinct tonal presentation and presentation stage compared to standard round-getter 6N6P or 6N30P variants, driving high demand and collector pricing 

• Massive 3D Depth: Unlike standard NEVZ or Reflector 6N6P tubes—which can sound flat, dry, or overly aggressive—the Foton square getter yields an incredibly organic, holographic, liquid midrange that mimics high-end Western European vintage tubes.
• Tight Low-End Transient Control: It matches the famously high transconductance of the 6N6P family but delivers tighter, punchier, and faster bass dynamics. [1]