Tube interference sounds

[Anders Brundell]

When I run my Tubefex in tube mode, weak and subtle interference sounds are heard when I pedal two or more strings, esp. high up the neck. I remember that from the tube amps I plaid when I was young, and now I wonder what causes those sounds.
You got to listen really close - they aren't that easy to hear.
Just curious – I don’t really need to know.
Mike Brown or anyone?

Anders

[Jerry Overstreet]

Anders, I defer to the experts here but since no one has replied I'll give you my unprofessional opinion. It's most likely harmonic overtones that you are hearing. I have a Mosvalve rig that produces this effect or one very similar at least. I only hear it playing here at home alone. It is annoying sometimes but it has such a great sound that I forgive it that characteristic. I romp on the thing pretty good out on the stage and have never noticed it there. Perhaps some of electronics techs here on the forum can offer you a more qualified opinion. JO

[Anders Brundell]

Thanks, Jerry!
Noone else than me have ever noticed this either, and it's no problem at all, neither on nor off stage, actually. I was just curious to know.

Anders

[Jerry Overstreet]

Yeah, me too. I'm not sure I understand it all that well myself.
There is more interesting discussion about even and odd order harmonics on the Black Box thread also. JO