I guess this forum has yet to pick up steam, but here goes anyway...

When I play a C# or D on the high E string (9th or 10th fret) I hear a note two octaveslower than the one I'm playing. Since note played would be about 600 Hz (IOW, right on the 5th harmonic of 120 Hz) I suspect it has something to do with power supply filtering.

If that's the case, why would I only hear this when I'm playing that C#? Wouldn't I hear a hum all the time? And what would be the fix, besides re-designing the whole power filtering section?

In what's becoming a recurring theme for me in these forums, I'm thinking of ways to tone down the highs on this amp...

With the bright switch in the down (500 pF) position, the amp has a boxy character that I like, but is still harsh. The middle position loses some of the boxiness. Since the 100 pF is then unusable for me, I'm thinking of replacing it with a larger cap.
Have any of you guys tried this or any similar ideas for taming, but not killing, the brightness in this amp?

What kind of tubes do you guys use/recommend for these? I've seen one user online recommending NOS GE EL84s for the power tubes, but I would think that in this amp, the pre-amp tubes are at least as critical.

I started with a set of TAD power tubes and re-issue Tung-Sol 12AX7s... there's a lot of character there, but it's a bit too clangy for my picking style and my guitars.

Best case, of course, would be new issue tubes...NOS prices are getting crazier each day.

Thanks in advance.

I've always been a big fan of EL84's...bright sound, fast attack, chimy cleans, etc. Over the years I've adjusted my playing style, pick choice (3.0 mm Stubbies), and guitar choices (mostly single coils where I used to be a "Les Paul guy") towards getting to that sound.

If I'd had this amp years ago, I could have kept the Les Pauls, the "easier" picks, etc. In fact, I love the boxy yet sweet sound of this amp, but with my guitars, picks, and style, I now need to tone down the brightness a bit. After I've had it for awhile, had the chance to play in a band situation, and taken the time to swap in different pre-amp tubes, I'll be ready to offer a more detailed opinion. In a nutshell, though, this is a great amp with a unique voice, at least compared to anything I've ever had.

And this is probably an old story, but dealing with Nik has been a pleasure. Long after he'd been paid, he was actively helping to straighten out a shipping glitch that was no fault of his. I know that some here in the US worry about doing business with an Asian company, but Nik's given me a better customer experience than some companies (no names) that I could drive to in a day. The long story short is that I'm trying to resist the temptation to order another amp or two, but I don't think I'll be able to hold out much longer.