What is the wattage at 4 ohms?

I was wondering if using a 4-ohm cabinet would result in more loudness on the Superblock. The product looks to be 25watts through an 8-ohm speaker. Is there any advantage to using an 8ohm as opposed to a 4ohm?

The power delivery is optimized for 8 ohms and will not increase into 4 ohms. You will find however that the 25 watt power sounds as big as a good tube amp, and plays well through lively 25 watt speakers such as the Greenback, which isn’t suited for higher power amps.