No one ever really doubled down if you look at the measurements. Companies understate the output at 8ohms so it looks like the amplifier is doubling at 4ohms. The trend now if to give the actual 8ohm power output and the actual 4ohm outputs. Some reviews can actually make it look like you are getting better results. The review may say though X amplifier's state output is 500 watts into 8ohms we measured 650 watts! It was always 650 watts and the company already knew it. They just made the math "perfect," for example by saying something like 500 watts into 8ohms and 1000 watts into 4ohms when it really was 650 into 8ohms and 1000 watts into 4ohms. Pick an amplifier that is stated to "double down" and then find a review with actual measurements.
