With these new inexpensive converters taking 6 volts to 12, has anyone successfully used one to convert only the headlights, and leaving the rest of the system at 6 volts? If yes, high and low beam?
My partner and I have been working on an all-purpose 6 to 12 volt converter box and have found that to make one that will handle much over 1 amp is not realistic.
if you run dual voltage your asking for trouble either run 6v or 12v these days you can buy reliable 6 volt gear and leds will generaly run between 6/36v and in the long term are a better buy
Any converter will have losses even the most efficient ones.
And there are 6v H4 bulbs and 7" inserts for them at fair prices...probably a lot less then 2 converters handling 10A+ will cost.
As was mentioned, converters that put out that type of amperage draw even more amperage to do that job. I wouldn't advise it on an original 35-amp generator system. It's just so much easier to adapt for modern high output bulbs.