Both my SET and my pushpull amps can be considered marginal, in terms of power, for my speakers. My SET amp is rated at something like 6.5 watts and the pushpull is 5 watts. I don't have any problems playing rock at fairly high volume.
Where some power issues do show up is with large-scale choral music. I do notice some compression and mild clipping if I try to play something like Rachmaninov's "Vespers" at somewhat high volume.
Where some power issues do show up is with large-scale choral music. I do notice some compression and mild clipping if I try to play something like Rachmaninov's "Vespers" at somewhat high volume.