Air Tight ATC-1 preamp question


How many of the 5 tubes in this pream are used for the line stage?
Thank you
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The two tubes inside the chassis are used for the linestage. There are three tubes on the left side of the chassis that are installed horizontally in a recessed area and these are for the phono stage. Great preamp by the way, I used to own one and I regret selling it even now. Happy listening!