Nuvista Tubes - General

I do not know what a Nuvista is so I hope someone hear can help you with that I do know what a Nuvistor is

Yes, excellent point. My bad. The essence of my question stems from Musical Fidelity amplifier products http://www.musicalfidelity.com/products/nu-vista/nu-vista-800 and how these types of tubes differ from the more commonly used (in audio) vacuum tubes.

I note they are using "nu-vista" in their own "marketing way", but the description does in fact indicate " Nuvistor tubes were invented in the 1950s to solve the many shortcomings of conventional tubes."

Therefore, given the titling of my post, please consider "nuvista" (and other permutations of nuvistor) to in fact mean "nuvistor", unless of course someone points out that in fact there is a functional difference on the basis of the label naming.

So what’s the down side?

They are a tube, and a tube needs to either have capacitor or transformer coupling, and the best transformer or tube coupling is no transformer or tube coupling.
Unless you go direct coupling with them then there are other pitfalls/compromises that have to be made.

BTW: I believe in the equipment I’ve worked on CDP and DAC, Musical Fidelity never used these tubes without having solid state transistor after them as proper output buffers.

Cheers George

Hi @georgehifi 

Your reply is a bit "over-my-head", but I glean the gist of what you're saying/writing is to avoid designs that use nuvistor tubes? 

To your point about needing to have capacitor or transformer coupling, is this something unique to nuvistors? (meaning vacuum tubes do not have capacitor or transformer coupling)

To your point about needing to have capacitor or transformer coupling, is this something unique to nuvistors?

No, directed at all tubes, unless direct output coupled.

I don't believe anyone has made a tube amp/preamp that is direct coupled (no caps or transformers in the signal path) from input to output, like you can with solid state.

Cheers George