The sound quality of the HR824s is very full and clean. They represent an accurate portrayal of what is being played and it is nice to be able to get a mix that sounds good on these and that will transfer well to other sets of speakers. The stereo image is more than satisfactory as it portrays a wide sound that covers the full range of human hearing. It is crisp sounding and has a nice low end response as well as a nice sounding mid range and high end. The dynamics are accurate as well, and I would say that these monitors have an overall great sounding that is true to what you are playing through them.
I've been using the Mackie HR824s for about three years. My favorite thing about them is just the overall sound quality. The price is also a big upside for these monitors, as they are very reasonably priced. I also have a pair of Yamaha NS10s and these are much fuller sounding in comparison, although they are more expensive. These have come down in price in the last few years, making them an even better choice for monitors. Mackie is known for making well made products, and these monitors are some of their best. I plan to hold on to my HR824s for a while as they are great sounding monitors at a great price.