I wonder if exceding the manufacturers max voltage is a wise decision. I know from experiments with early [homemade] car computer mp3 players, that getting regulated 5 volt IC power from typical 13.8 VDC vehicles produced a lot of unwanted heat. Also you mention blowing fuses... fuses as I undertand them, are more concerned with amperage than voltage.
Of course, I don't know what the empeg uses for volatage regulation and I could just be overly cautious.
I was recently in error when I had my local tire shop install the "Smartire" system
http://drive.to/DSM . It transmits telemetry (pressure and temp.) from each wheel to a central processing display. I told them not to wire anything into my dash (I would do it myself) and just mount the tire tranponders. Of course, it was the first such system they saw and they wanted to play with it... and they wired it in with the polarity reversed. They said it was dead. I said they killed it ;) but when I wired it up correctly, it worked! The manufacturer installed reverse polarity protection diodes in it! So my tyres might be smarter than all those that installed them after all.
Anyway, I know there was a comment about more voltage in the empeg yielding better signal:noise ratio but it didn't seem "official" to me.
Regards,
Mark
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