I was wondering if something along these lines might work well. I have 2pair of well made small signal type transformers. I was considering a 12AU7 as a cathode follower with an out put around 400ohms impedance driving the 600ohm side of my interstage transformer and then taking the 25ohm side of said transformer to drive my output tube. Well what type of performance/general behavior I might I observe- not so mush will it work as opposed to how well it would work
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Some sort of single-ended transistor amplifier driving a telephone line, a telephone repeater maybe? The specified 0.5 dB frequency range is just a bit wider than the traditional 300 Hz to 3400 Hz of a telephone landline, there is a pretty good insulation between primary and secondary and 600 ohm is a common nominal impedance for telephone lines.
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A cathode follower should drive a considerably higher impedance than its output impedance if you want maximum voltage swing with low distortion. And the 5 : 1 voltage step-down is another step in the wrong direction.
0.5 dB frequency range is just a bit wider than the traditional 300 Hz to 3400 Hz of a telephone landline, there is a pretty good
I’m still figuring out the quote function and I will…lol so with the narrow bandwidth of these transformers they were likely used in telephony and are probably not truly useful except to learn from-
to Tom:
Ok I was under the impression that better signal transfer occurred when impedances were matched and I thought a low impedance should drive a higher impedance and that was a good thing- I’m really trying to sort this out so I can think clearly about this
Triodes need to see a load of 2.5 to 5 X their rp.
The CF is no better at driving 600 Ohms, the load to the tube is still 600 Ohms.
The CF is no better at driving 600 Ohms, the load to the tube is still 600 Ohms.
I cant really think of a good use for these in Audio the power rating is of more concern than the frequency response.
The low power rating suggests to me that they need to be used early on like a moving coil step up, but the ratio isn't right for a moving coil step up...
You could design something in order to put them to use but it wouldn't be ideal...
Id move on to other things...
The low power rating suggests to me that they need to be used early on like a moving coil step up, but the ratio isn't right for a moving coil step up...
You could design something in order to put them to use but it wouldn't be ideal...
Id move on to other things...