According to the Getting Started/Replacing Tubes page of the manual(s):
"Freya(Freya+) accommodates any 6SN7, 6N8S, or 5692 tube type..."
6sn7 tubes and Schiit Freya +
Hi all-
I’m a new Freya plus owner and just getting ready to move beyond the Stock J&J tubes. I was reading a thread about 6sn7 tubes and saw this—
The 6SN7GTA and GTB versions were introduced in 1950 and 1954 respectively. They have ‘upgraded’ ratings, which are as follows.
GTA: maximum anode dissipation upgraded to 5W (the GT is rated for 2.5W)
GTB: identical to the GTA, but with a controlled heater warm up time for use in equipment with 600mA heater strings
This is significant because it means that a circuit designed around the 6SN7GTA/GTB cannot have 6SN7GTs substituted into it. Substituting a GT in place of a GTA/GTB in your equipment will precipitate its rapid destruction and possibly damage your equipment.
GTA: maximum anode dissipation upgraded to 5W (the GT is rated for 2.5W)
GTB: identical to the GTA, but with a controlled heater warm up time for use in equipment with 600mA heater strings
This is significant because it means that a circuit designed around the 6SN7GTA/GTB cannot have 6SN7GTs substituted into it. Substituting a GT in place of a GTA/GTB in your equipment will precipitate its rapid destruction and possibly damage your equipment.
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I recently purchased Sylvania 6SN7 GTAs (chrome domes) and Hytron VT 231 6SN7 GTs. Are both okay to use in my Schiit Freya +?
Thank you! Margot