Max,
I don't have the old Faulhaber motor, I returned it to Eldon. But I do remember checking whether it was a 6 volt or a 12 volt, and it said 6 volts. The gearhead was smaller in diameter than the motor.
Interestingly, the new motor I received from Eldon also is 6 volts, but the gearhead is the same diameter as the motor. The gearhead is also longer than I remember.
Either way, I am happy now. The slow speed control is great, and the top speed of about 40 mph is about the speed I run trains anyway.
On my L1, I am replacing the stock Kato motor with a Mashima 1024 can motor. This motor has a lot of torque and a lower top end of about 13,000 RPMs no load. It will be interesting to see how this motor stacks up.
Mike