We report on the generation of 94-fs pulses with 12.5-W average output power from an 80-MHz Yb3+:CaGdAlO4(Yb:CALGO) oscillator with pulse energies and peak power levels higher than 150-nJ and 1.45-MW, respectively. To the
best of our knowledge, this is the highest average power ever reported for a sub-100-fs bulk oscillator. Average output
power levels higher than 10-W were also achieved in lower repetition rate oscillators at 23.7 MHz and 42.5 MHz with
pulse durations ranging from 141-fs to 323-fs and corresponding pulse energies as high as 0.42 μJ. In all experiments
stable and self-starting mode-locking with transform-limited pulses and beam quality factors better than M2<1.1 were
achieved. Continuous tunability in mode-locked operation between 1026-nm and 1052-nm was also demonstrated. We
believe that shorter pulses at higher average output powers should be possible and - combined with extended cavities -
such laser systems could reach the μJ pulse energy level with peak powers in the 10-MW regime.