Tube pedal question.

[Kesh]

I read merlinb's article on low voltage tubes, where he recommends the 12au7 and says the ECC88 would be ok if it didn't have so much grid current.

Well I got some 6n11s which are a Chinese equivalent and they seem to have hardly any grid current until Vgk is almost zero. B+ at 15V.

I basically measured voltage from grid to ground across the 1M grid leak resistor on a common cathode set up with no input. I varied the cathode resistor and took measurements. My DMM is 10M impedance.

My question: is this a valid way to measure low voltage grid current?

[brett]

Hi
I'm no expert, but that sounds as good as any way of simply measuring grid current (doing it dynamically might be even better, but could get complicated).
But to go back to the original premise - that grid current is an issue. My experience says that the output characteristics at low voltages are very important (output impedance, for example). It's not just one characteristic or another. Buffered inputs and outputs can help overcome some of the limitations.
cheers