Battery tone?

[lars]

I know some fuzz pedals will change tone as the battery gets weak, but the idea that "alkaline batteries eat your tone"? This has gotten as bad as true bypass...
http://billionairetone.com/product/battery-billionaire/

[WormBoy]

Hmm, this is just a box to hold four 9V batteries (check out the manual). With things like the fuzz face, there is a difference between a power supply and a battery, and also between alkaline and carbon-zinc batteries. I think it is one of those impedance things  . From my limited experience, the difference was never large enough to bother me, but it may just be my ears ...

[thesmokingman]

chemical batteries provide relatively consistent voltage until their internal resistance becomes too great to overcome ... at which point they're "dying" by not only no longer providing the proper voltage but also nearly no amperage. 
that isn't the same as voltage starvation even if we refer to it as "dying battery simulation" because you're still providing a consistent amperage, just at a lower voltage(see ohm's law) ... still fun to be had here, consider the stab control of the fuzz factory
the supposed battery mojo, which I actually agree with when it comes to germanium fuzz faces, comes from the differences in discharge rate between carbon comp batteries and alkaline ... not whether the battery is dying or not