Kamox wrote:

Hello,
I'm going to make a 300B SE amp (Anzai Zaika project, 6SJ7 as driver
tube) and, as my first DIY tube amp, I didn't want to spend too much:
I've therefore bought a unmatched pair of 300B by CVC. The retailer
told me that these are good tubes, made in China according to CVC (UK)
specs. I paid 150 euros for them.
Have I been robbed?

No, not unless they pointed a gun at you ;-)

Do you know this "manufacturer"?

The tubes should be fine. Chelmer Valve tests their tubes, so they
should be ok. The price is about the same as Valve Art 300Bs from AES.

Best regards,

Mikkel C. Simonsen