This is old schematic of Tube Phono Pre-Amp - 12AT7. Because The 12AT7 is not the most commonly used preamp tube in audio. That distinction probably falls to the 12AX7. Manufacturer :Type : Tube Phono PreampNumber Of Tubes : 2/1Tube Type : 12at7Voltage : 120VHigh Resolution Scan : AvailableSome notes...

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