Near field use on 87db speakers in a masive room.

[Paul Birkeland]

Do you have a link to the post about the varieties with insufficient voltage rating? (or which tube is not supposed to be adequately rated?)

[currly30]

Be aware that the maximum plate voltage rating of the 6n3p is 160v, whereas the 5670 is rated for 330v. In Kaiju, the regulator section runs at 300v, and the amplifier section at 175v. Use of the 6n3p will risk failure of the tube and collateral damage to other parts of the amp.

[Paul Birkeland]

I'm not certain where PJ is finding that number, as the 6N3P  shows 300V is acceptable for plate voltage:
https://frank.pocnet.net/sheets/113/6/6N3P.pdf
I've gone cross-eyed at times trying to keep Russian equivalent tube types straight in my head, so perhaps there's another tube that's maybe a letter off with that restriction, or there's a different grade that's derated, or even a conflicting datasheet out there!

[Paul Joppa]

 I have edited that post today. If you read the posts that follow it, you'll get the full story. It's complicated.

Sorry for the confusion, I should have edited the post earlier.

[Paul Birkeland]

So the E suffix ends up being the issue it seems, or perhaps the derated voltage is part of the trade for longer life? 

[currly30]

Interesting.

[currly30]

Are there any input tubes that can be used with just an adapter or would anything besides the 5670 line be a sonic downgrade? Does the Kaiju require a pre-amp?

[Paul Joppa]

Kaiju was designed around the 5670, not with alternative tubes in mind. Most candidate drivers will need changes to the voltages and currents; some will also require an adapter. I looked at quite a number of candidates to pick the 5670, but have not done the detailed calculations for any alternatives, so I can't at this point say which might or might not be made to work out.

Sonic upgrades and downgrades are so much personal taste that I can't usefully comment.

Kaiju will usually need a preamp in most systems. There are exceptions, but not that many.

[currly30]

Thank you for the info. I take it the BeePre2 was designed to work in tandem with the Kaiju?

[Doc B.]

BeePre2 works well with lots of amps and, yes, it is the mate to the Kaiju.

[currly30]

BeePre2 works well with lots of amps and, yes, it is the mate to the Kaiju.

Thanks for the information. If I get the BeePre2 and the Kaiju would the 300Bs in both need to be matched?  Would upgrading the tube on only 1 be waste?

[currly30]

Has anyone tried these tubes on either the Kaiju or the BeePre2? https://www.aliexpress.com/item/3256804189718927.html?spm=a2g0o.productlist.0.0.5dd43a53ypVCD6&algo_pvid=51ff7f37-7bc3-4439-856a-ab69f1a883a4&algo_exp_id=51ff7f37-7bc3-4439-856a-ab69f1a883a4-5&pdp_ext_f=%7B%22sku_id%22%3A%2212000028959587513%22%7D&pdp_npi=2%40dis%21USD%21800.8%21400.4%21%21%21%21%21%40210318cf16607231954034629e8ce0%2112000028959587513%21sea&curPageLogUid=yCZ6aMA01TJ1

[Paul Birkeland]

If there's no datasheet for that tube, I would hold off on using it until they publish one.

[tsingle999]

<<If I get the BeePre2 and the Kaiju would the 300Bs in both need to be matched?  Would upgrading the tube on only 1 be waste?>>
I have the beepre and a 300b BH amp. I think one pair of upgraded tubes is worth it. The nice thing is you can try them in both the amp and pre and see where you like them better.

[currly30]

If there's no datasheet for that tube, I would hold off on using it until they publish one.

I couldn't find a datasheet either. The most I can find is that it supports up to 16W output.

https://www.audionirvana.org/forum/the-audio-vault/electronics/149947-carbon-spray-new-changsha-shuguang-tube-52b-ta-on-behalf-of-300b-and-6300b