The Digidesign RM1s are a pair of high quality studio monitors. They are active monitors, so an external power amplifier is not necessary. They are pretty big in size but aren't too big where you couldn't transport them if you want to. They are just about the perfect size for studio monitors in my opinion as they are easy to move but still have enough power to bust out that low end.
The sound of the Digidesign RM1s is absolutely awesome. It has an extremely full sound that makes these monitors great for uses of all types including mixing and monitoring. It definitely gives you an accurate read on what you play through them and they cover the entire frequency spectrum precisely and accurately. While they are very full bodied sounding, they aren't unrealistic and I find that things that I mix on these monitors will transfer over to other listening devices very well. It definitely has good dynamics overall and also have more than a satisfactory stereo imaging. Overall, the Digidesign RM1s have a nice low end presence as well as crisp mid range and high end.
I first used the Digidesign RM1s a few years ago and they are some of my favorite monitors out there. Since they are designed for professional engineers, the price isn't at all cheap but if you are a professional looking to get a top notch pair of studio monitors, this is the price you must pay. I love these monitors for any sort of application, but where they really excel is during mixing as the mixes will transfer over very well in my opinion. While I didn't expect a pair of monitors made by Digidesign to be all that great, I was pleasantly surprised with the results I found. If you are looking for a nice set of studio monitors that you can get accurate mixes on, the Digidesign RM1s are more than worthy of a try.