50V DC Power

DC-DC Power Supplies

Since the HR50+ is so small and light, it seems like a great choice for a portable/mobile amplifier. That is until you try to power it. Fortunately there are inexpensive DC-DC converters available. I have had good results with this 1200W Boost Converter and it may seem like 1200W is overkill for a 100W amplifier but when you dive into the ratings you can see where the problem is. It's rated at an input of 10-60V and an output of 12-83V. The HR50+ needs 50V at 4 amps, which is well under the device's output rating of 10 amps. But if the input voltage is 12V and the supply is 90% efficient, the input current will be 18.5A wich is dangerously close to the 20A max input rating of the device. If you are using a decent 13.8V power source this converter should be fine but if you intend to use a battery that will drop below 12V as it discharges, you might want to lower the output voltage to 40-45V to prevent blowing the input fuse or tripping the current limit.

AC-DC Power Supplies

There are several choices for AC input power supplied that supply a 48-50V 4A DC output.