Excellent points have been made above. I would add a note of caution about the possibility of clipping the amp and damaging your tweeters as a result.
Stereophile measured your speakers
as having a sensitivity of about 87db for 2.83 volts input at 1 meter. Given the 4 ohm nominal impedance, that corresponds to about 84db for 1 watt input, at 1 meter, which is quite low for use with a 27W amplifier.
That is of particular concern if you are listening to material with wide dynamic range, meaning a large difference in volume between the loudest peaks and soft passages. Well recorded classical symphonic music is a good example of that. That will cause you to turn up the volume control much higher than you would for compressed material having narrow dynamic range, resulting in power demand on peaks that greatly exceeds the amp's capability. The resulting distorted, clipped waveform will contain high frequency energy that is not present in the original material, which the speaker's crossover will route to the tweeter.
So I would suggest avoiding material that has wide dynamic range, and being careful to not turn up the volume to the point of audible distortion.