The Svetlana™ 12AX7 is a miniature glass-envelope small-signal dual triode intended for use as a low-noise preamplifier for audio applications. It is a direct plug-in replacement for any 12AX7, 7025 or ECC83 in music or audio amplifiers. All ratings of the Svetlana 12AX7 meet or exceed those of the original version; top-quality cathode materials and extensive aging yield outstanding performance in high-fidelity amplifiers. The Svetlana 12AX7 is made exclusively at the Svetlana Electron Devices factory in St. Petersburg, Russia.
The 12AX7 from Svetlana has been originally intended as an OEM part in some Marshall amps. These 12AX7s has great punch, harmonics and definition.
Listening test. Torres Dual Marshall amp.
These are definitely not the earlier batch of these tubes. They are very nicely made with large chrome plates and great quality construction.
Tone is very rich with a unique focused bass response, warm midrange and noticeably sweet high frequencies.
Under lots of distortion this tube really has its own sound.
No squealing and a very tight bass response with a pronounced upper midrange "singing" quality.