The 3020 may have been rated at a mere 20 watts per channel, but it had 3 dB of headroom. Hence, it could deliver 40 watts into 8 ohm loads, 58 watts in 4 ohms, and 72 watts into 2 ohms for brief periods of time. I doubt you can find a receiver today that safely drives 2-ohm loads.
it has a very nice phono section too!!
comes with a 30 warranty