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Preamp tube voltage ratings
Hi Guys

Despite the fact TUT has been out since 1995, people still ask about the 300V rating for 12AX7 and similar preamp tubes.

12AX7 has a flash-over rating in excess of 540V.

The reason for the 300V rating is to accommodate the flyback voltage with an inductive load, such as a transformer feeding the next stage.

Have fun
(09-04-2018, 04:04 PM)TestĀ UserĀ 1 Wrote: Just a test post from Test User 1.
What voltage rating do YOU have Wink

That's interesting about the preamp tubes. My marshall has more than 300V at the preamp and splitter - more like 450 or something. Good to know the tubes can survive.

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