Would you pay $500 - $650 for an NOS AC 701 Tube?

[Winetree]

I could possibly  see paying that for an original mic replacement tube,
But would you pay $500 - $650 for an NOS AC 701 Tube for a Clone mic build?

 

[emrr]

No.
1) it's a clone.  Wishful thinking at best.  Use another tube, it will make less difference than everything else. 
2) plenty of original mics that will need that tube, not cool to make even competition for it. 

 

[ln76d]

I could possibly  see paying that for an original mic replacement tube,
But would you pay $500 - $650 for an NOS AC 701 Tube for a Clone mic build?

No

 

[dmp]

I agree with "no"
I know the AC701 is special in specs for a mic build, but in practice I've found other sub-miniature tubes suitable for the job.
I have three mics built with 5840 and none of them have noticeable noise and the tone is great. (disclaimer: I haven't compared to a real AC701)
The only reason I might buy and build a mic with a $600 AC701 is to compare - but then I'd re-sell it.

 

[Phrazemaster]

Yes. I did. For an M49 clone. Still building.

 

[Nyquist]

No. It would be touch and go in any case unless you can confirm 100% the AC701 is quiet with no microphonics. Most you see on Ebay will be duds.  There are a few folks that have a small to large collection of these tubes and they'll only sell to repairers or people with original vintage mics.

Like mentioned above many DIY'ers including some manufactures use the 5840 whit  great success. Including my yours truly.

 

[Banzai]

It's not a rare tube, just expensive. So if you can afford it, go for it!

There's no moral responsibility to think about other people who might need them, and those who have bought all of em up to price gouge the market, they certainly didn't care...

 

[Pip]

It's not a rare tube, just expensive. So if you can afford it, go for it!

There's no moral responsibility to think about other people who might need them, and those who have bought all of em up to price gouge the market, they certainly didn't care...

I disagree with the first statement.  Although the tube itself may not be "rare" (I don't have the numbers to disagree) I know that microphone grade and tested are rare and that you are in a crapshoot everytime you buy one. P.S. That goes for any tube on the planet just read these boards for much discussion on tube selection for the daunting task of low noise tube mics.  Microphone luminaries far more reputable than myself will go as far as to tell you that all the AC701's available either failed the test for a mic and where cast back or they never even cleared the hurdle for the much sought after "K" red dot designation that meant they where low noise to start out.

I don't think this is a moral play either.

I do think that there are plenty of tubes out there that fill the bill. I too am a big fan of the 5840 if that size device is called for.