1. The problem statement, all variables and given/known data We are modeling the tweeter of speaker and its enclosure with the circuit shown in the figure attached. We are also given an "magnitude of input impedance" curve as shown in the figure with various data points. With access to these various data points we are able to determine the various components values within the equivalent circuit. 2. Relevant equations 3. The attempt at a solution At low frequencies only R1 is visible, thus |Zin| = R1. At the resonance frequency due to the enclose we will see R1 and R2 in series, thus the peak value in the |Zin| graph is R1 + R2. Since we know R1 already we can solve R2. At high frequencies we will see R1 in series with L1, but due to the high frequency we can essentially neglect R1, thus |Zin| ≈ ωL1. So the linear portion seen after the hump due to the resonance from the encloser can be thought to have an angle β, such that tanβ = slope = L1. Thus we can use the data computes to compute the slope on this section of the curve and solve for L1. Now that part I am stuck on is with regards to L2 and C2. Is it possible to find L2 and C2 uniquely? If so, how? Thanks again!