71A is a vintage direct heat triode power tube for audio amplifier. 71A is firstly made by Cunningham as CX-371A in USA in 1930s. Although 71A is a low plate voltage (180V max.) and low ouput power (0.8W in SE class A) triode, it can drive loudspeakers in high sensitivity. Nowadays, more and more audiophiles like the sound of vintage 71A.
http://www.mif.pg.gda.pl/homepages/frank/sheets/029/7/71A.pdf
We started to make our first 71A amplifier.
http://www.mif.pg.gda.pl/homepages/frank/sheets/029/7/71A.pdf
We started to make our first 71A amplifier.
RCA 6SN7GT, RCA UX-71A and Mazda 5Y3GB.
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This very rare and expensive vintage ballon shaped UX-71A triode (171A, 271A, 371A) delivers sweet, soft and smooth sound.
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This is the output transformers for 71A single end. The primary impedance is 5K and secondary impedance is 8 ohms and 16 ohms. The output power is 7W. The steel core used is Z11. The transformers were made in Poshan, Hong Kong.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Beautiful! You are giving me GAS!
Thank you.
This is the output transformers for 71A single end. The primary impedance is 5K and secondary impedance is 8 ohms and 16 ohms. The output power is 7W.
I think you mean the output power is ~ 0.7W
I am looking forward to using some of these in an amp project - supposedly, they present music with a nice sense of delicacy and nuance, though can sound (visually) flat at times... We will see.
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