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Amazon.com: 62W EI Audio Power Supply high Voltage Transformer Dual 300V+13.6V+ 6.3V for Tube preamplifier Phono Amplifier SY2206-12784A1 : Industrial & Scientific
1 Pair of 50W 320V+Dual 10V+6.3V Audio toroidal Transformer JADIS JP200 Tube preamplifier Power Supply - Amazon.com
Amazon.com: 100W Audio EI Type Transformer Output 0V-230V-290V/0.2A+6.3V/4A Power Transformer for EL34 Class A Tube Amplifier (Size : 230V) : Industrial & Scientific