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"I am also back using E180CC (Philips SQ) now for the gain tubes. Tried a pair of 6414 tubes following the Genalex 12AT7 (labelled A2900). I have yet to try the Telefunken ECC801S, Mullard CV4024 and 7316. \n \n\n\n\tSo far I liked the Genalex A2900 and Siemens ECC801S best overall for the gain tubes.\n \n\n\n\tI also heard an improvement when I replaced the Tele 12AX7 with Brimar CV4004 for the driver tubes but the difference is not nearly as significant as changing the gain tubes. It may also be due to the fact that the Tele 12AX7 I was using are used tubes with unknown mileage. \n \n\n\n\tJust my 2 cents worth and should be taken with a large grain of salt - I was merely experimenting and most of the tubes used were NOS with only a few hours running.\n \n\n\n\t \n "
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