An extensive configuration interaction (CI) scheme and the R-matrix method are combined to calculate the x-ray transmission spectrum for high-power laser-produced Al plasmas in local thermodynamic equilibrium by using the detailed-term-accounting (DTA) approximation. All atomic parameters such as state levels and photoabsorption cross sections for different ionization stages are obtained by using the CI and R-matrix method. Special attention is given to the effects of autoionizing resonance broadening on the transmission. A large difference exists between the convergence of the results with and without taking account of autoionizing resonance broadening when the autoionization resonance broadening is the major broadening mechanism. This shows that autoionizing resonance widths of the K-shell excited states have large effects and should be considered to interpret the spectral-resolved transmission.