Calculated I_N2H⁺/I_HCN ratios (left) from our measurements and I_HCN/I_CO ratios (middle) from EMPIRE survey data (Jiménez-Donaire et al. 2019), as a function of galactocentric radius in NGC 6946. Each observed position is indicated. The right panel shows I_N2H⁺/I_HCN as a function of I_HCN/I_CO, illustrating that I_N2H⁺/I_HCN remains approximately constant, while f_dense changes by a factor of ∼4. The purple region shows the range of previous literature values found for the central regions of starburst galaxies, AGNs, and ULIRGs (e.g., Mauersberger & Henkel 1991; Watanabe et al. 2014; Aladro et al. 2015; Nishimura et al. 2016b; Eibensteiner et al. 2022, but see also Fig. 4).