DSP Enable lowers Sound Quality

You should definitely try room correction, whatever small decrease in SQ there might be because of DSP is nothing compared to the improvements a well made room correction does.

Either try my guide: A guide how to do room correction and use it in Roon or use HomeAudioFidelity, check this thread: Roon & Home Audio Fidelity (Room Correction / convolution filter creation)

You will need REW and a microphone either way.