How did it get to be so much?

[4krow]

Just browsing around some off the grid tubes, I came across the 13cw4 triode, 'NuVista' tube. Man, my head spins. Sure, I knew there were a bunch of tubes made back in the day, and yet, everywhere I turn there are these oddball little guys on each corner. Guess these are hi-mu tubes made for such applications as tuners. Question that I have is how usable are they for audio? Something says, not a bad choice.

[Paul Birkeland]

Small devices always have small dissipations, which tends to limit their usefulness. 

[4krow]

 Thanks Paul,

  I am getting it a bit more now. Just as the 'Nutube" needed a transistor both before and after to make it work at higher levels, so does this 'NuVista' tube. So, at best this can be used as a hybred type of circuit. Also noted is the strange physical pin arrangement on the bottom of the tube.

[Doc B.]

No need for a transistor. Look up Nuvistor based VHF RF amps for FM tuners.

[Paul Birkeland]

  I am getting it a bit more now. Just as the 'Nutube" needed a transistor both before and after to make it work at higher levels,

The signal level had nothing to do with the need for buffering, it was the completely wimpy nature of the NuTube that made it completely worthless on its own.

[4krow]

Now see Paul, I have to rethink this all over again. AND it makes me wonder why they bothered with the NuTube in the first place? I mean, if you are starting from scratch or at least have that option, the world (of tubes) is your oyster.

[Paul Birkeland]

It might be the first step in other future products that are a bit bigger/quieter/more capable.

Such a small device would be a good toe in the water to see what the interest looks like. 

[4krow]

Yes, good point there. In fact, just a moment ago, I soldered the last wire in place for a small pre-amp/headphone amp with the NuTube. I have done it before, but wanted to add a few options in this experiment.
 So far so good.

[Paul Joppa]

Wikipedia has a short article. I have heard that they are very microphonic; the metal body rings for a very long time if it is mechanically excited. That's probably the biggest limitation for audio use.

[4krow]

This is all good information. I know that other tubes have the issue of microphonics as well. The 3S4, has much less than the NuTube. Now it doesn't surprise me that the 13cw4 doea also, if size has anything to do with it. The Nutube is so microphonic that even using the selector switch brings about a twitch of resonance. I have tried just about all that I am willing to do for this issue.