Other possibility is as follows.
We assume that the total gravitational energy emitted as gravitational waves due to the formation of GW170814 is given by $-E_{1}$ where
and G is the gravitational constant, M1 and M2 are the masses of the two black holes and $h_b$ is the gravitational Planck constant. In order to compute the value of $h_b$ we assume that
Then we obtain
it is to say
$$h_b = 0.1035899036 × 10^{46} J-s$$
Using such value we deduce that the frequency of the gravitational wave emitted due to the formation of GW170814 is $82.50898602 $ hertz. The corresponding period is $0.01211989200$ seconds and the corresponding wave length is $3635.967600$ Km.
Do you agree?
Similar computations can be performed for GW150914 and GW170104 and the obtained results are very good approximations to the observed values.