Spectroelectrochemical studies were used to investigate the photophysics of electrochemically doped (6,5) SWNTs. The optical properties of SWNT ensembles were here studied by quasi simultaneous absorption and photoluminescence spectroscopy over the NIR and VIS spectral ranges. This allowed correlating changes in the oscillator strength of first and second subband excitons with changes in the photoluminescence signals from the bright singlet exciton. The data thus provides a key link between photoluminescence quantum yields affecting PL measurements and the extent of SWNT p or n doping as evidenced by absorption spectra. The data also provides evidence for a shift of oscillator strength from exciton transitions to free carrier type transitions in higher lying subbands.