A:Answer If you use the SPEAKER feature and turn the volume to the highest setting, the audio volume is very loud and quality of talk is not affected.
Also, there are volume settings for the RINGER that can make the sound heard from quite a distance. I have one handset in my home office with RINGER on low (so as not to be disturbed during the work day), and other handset is located in my kitchen (approx 35' to 45' away). That RINGER is set on the 3rd highest volume and I can still hear it in my office. It could go 2 settings higher, if needed.
Hope this helps!