What is the main difference between the 1961 Monitors and 1723 Bookshelf S?
The key differences will be Sensitivity, dispersion and bass output.
Sensitivity
The monitors will have a sensitivity of 87dB, whereas the bookshelves have a sensitivity of 84dB. This means that for any given wattage, the 1961 monitors will be 3dB louder than the bookshelves.
Dispersion
The bookshelf only consists of a tweeter and woofer, whereas the monitor has 2 woofers surrounding the tweeter. Due to this design difference, the bookshelf will have a wider radiation pattern, and in turn a bigger soundstage. The difference will be noticeable both horizontally, but especially vertically. This isn’t a flaw in the MTM design, but made by choice: This ensures that the monitors are less affected by ceiling and floor reflections, which can be beneficial, especially if the speakers are placed a little far away from the listening position.
Bass output
The main difference here, is that the 1723 bookshelf s can accommodate a crossover frequency of 80Hz, whereas the 1961 monitors will perform better with a slightly higher crossover frequency of around 100-110Hz. As the frequency increases, it becomes more and more directional. Some people are more susceptible to this, and it can be noticeable in the 110Hz region which can lead to localization issues if you need to place the subwoofer somewhere that is not next to the front speakers.