A tade more briteness - Jolida 302b. Tubes?

Completely agree c Trelja. I have Ei EL34 & Ei 12AU7. I found them extremely good and reliable for the money and have the extended highs you are looking for if you are not into NOS.

Howard, I could NOT agree with you any more strongly!!!

My Jadis Orchestra Reference was a very good amplifier when I began with it. A silver power cord raised its level of performance by providing me with blacker blackgrounds, lower noise, better bass, more clarity, and more sparkle. The HGA SilverLace upped it even more. And, when I retubed with JJ Blue Glass E34L tubes, it became, in my opinion, a world class amplifier.

Should I have just accepted the performance I got right out of the box? That would have been VERY stupid. For a total outlay of less than $500, in my opinion, I raised the bar of my component from competing with $5000 competition to competing with anything. If I wanted to do that otherwise, I'd need to move into a completely different amplifier, at 2 - 3 times the price.

Glai, I think we agree on the Ei. They certainly are special. Ultimately, I did find Mullard Blackburn tubes to be clearly better than the Ei, but for about $7/tube versus $35 - $50, the value for money is with the Ei in spades. You really have to spend 7 - 10X more to beat them.

I cannot address your Jolida. However, in my Conrad Johnson MV-55, I have evolved my EL-34's from Svetlana to JJ to Electro Harmonix (EL34H) and finally have nice treble!

Can I substitute the 12AT7 with EI 12AU7 in the Jolida 302b?

I would change the input tubes with mullards or others. They make a big difference to the stock tubes.

Or look into an ASL aq1001DT - it is a tube integrated that sounds like a tube and SS - which will brighten things up. At least it has solid highs for me.