Yes, it is important. Especially at the higher quality and price levels, where very small sonic details make a difference.
The impedance loading for a cartridge not only affects the sonic flavor of the cartridge, but can also influence the output level and also the internal damping behavior of the cartridge.
It is important to note, however, that not everybody agrees about what is the best sounding load for many cartridges, and it can be somewhat different depending upon your system and tastes.
A phono preamp that allows a wide range of loads to be applied to the cartridge gives you the ability to experiment with loads that might sound best to you. In the absence of multiple load settings, some makers give you the ability to change precision resistors to the value that suits you. You can then buy a range of these resistors, and do the changing yourself.
The impedance loading for a cartridge not only affects the sonic flavor of the cartridge, but can also influence the output level and also the internal damping behavior of the cartridge.
It is important to note, however, that not everybody agrees about what is the best sounding load for many cartridges, and it can be somewhat different depending upon your system and tastes.
A phono preamp that allows a wide range of loads to be applied to the cartridge gives you the ability to experiment with loads that might sound best to you. In the absence of multiple load settings, some makers give you the ability to change precision resistors to the value that suits you. You can then buy a range of these resistors, and do the changing yourself.