Hello! This is my first post, and its purpose is to answer a question I could not find the answer to, and hopefully help others who have this same question: The Orange OB1 amps list the total wattage at 500W but do not specify the wattage at which impedance. While it is implied this is 500W at 4ohms, I didn't know for certain what the max wattage was at 8ohms. Per an email to Orange the response is as follows: "Hi Liam, The OB1-500 will produce 500W @ 4 Ohms and around 350W @ 8 Ohms. A pair of 400W 8 Ohm cabinets will be suitable for your amp. Our OBC112 lightweight cab is rated at 400W and 8 Ohms - in case you want to consider it. "