Every speaker in existence has been tuned by the designer. Just like a piano needs to be tuned a speaker needs to be tuned also. What this involves is trying out different crossover topologies. You might do a fourth order or a 2nd order. You might aim for a flat response or a U shaped curve. The possibilities are endless.
Diferent values of capacitors and inductors are then tried to fine tune the sound even more. This is not something that can be measured or calculated. It has to be done by ear until the correct values are found.
The trouble is of course, the sound you get from a speaker depends on the room its placed in and the listeners hearing response. The yamaha ns10s are tuned with a peak in the mids and ZERO bass so sound horrific. Despite this they are regarded as reference speakers by studio professionals. This means the studio Pros dont understand what good sound is. Why would anybody bother using such cheap monitors as a reference? It is bizarre. Audiophile speakers are designed to sound good by people that care about good sound. Studio monitors are designed to sound bad so that mix engineers are forced to mix their recordings to sound as good as it can through these bad speakers. The theory is that these recordings will then sound good on everything. It is a bunch of hogwash and BS.
Most studio monitors are rubbish for enjoyment. Both audiophiles and studio Pros agree on that at least. There are some speakers such as B&W nautilus that are marketed as both audiophile and studio speakers hence they are used by both sides of the market.