Brian,
At the end of the day its what you
hear that makes a musical product 'good' or just 'average'. I would never buy a keyboard of organ without listening to it first! It's no good going by the 'written' specification as when you get it home and listen to it, it may not come up to what you were expecting. So being able to 'Equalise' your keyboard in this way (ie. to 'balance' the sounds to what you like to hear) is paramount, to my way of thinking. This is what your LINK has to say about all this:
Hello! We thought we would share with you our EQ settings for Genos.
As with all Yamaha products, the keyboards arrive from the factory with a FLAT EQ.
EQ is like the bass and treble control of your old Stereo, and the more you adjust, the warmer or brighter sound you get.
So, we would like to give you the EQ setting that we use, and we find this works brilliantly through big and small speakers, as well as headphones.
So if you have a Genos, check this out!
Hugh