68% and 95% constraints on the angular diameter distance D_A(z = 0.57) and Hubble parameter H(z = 0.57) from the Anderson et al. (2014) analysis of the BOSS CMASS-DR11 sample. The fiducial sound horizon adopted by Anderson et al. (2014) is . Samples from the Planck TT+lowP+lensing chains are plotted coloured by their value of Ω_ch², showing consistency of the data, but also that the BAO measurement can tighten the Planck constraints on the matter density.