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We present a multi-wavelength characterisation of the planetary nebula (PN)NGC 6905 and its [Wolf-Rayet]-type ([WR]) central star (CSPN) HD 193949. OurNordic Optical Telescope (NOT) Alhambra Faint Object Spectrograph and Camera(ALFOSC) spectra and images unveil in unprecedented detail the high-ionizationstructure of NGC 6905. The high-quality spectra of HD 193949 allowed us todetect more than 20 WR features including the characteristic O-bump, blue bumpand red bump, which suggests a spectral type no later than a [WO2]-subtype.Moreover we detect the Ne VII and Ne VIII broad emission lines, rendering HD193949 yet another CSPN with $T_\mathrm{eff}\lesssim150$ kK exhibiting suchstellar emission lines. We studied the physical properties ($T_\mathrm{e}$ and$n_\mathrm{e}$) and chemical abundances of different regions within NGC 6905including its low-ionization clumps; abundances are found to be homogeneous. Weused the PoWR stellar atmosphere code to model the spectrum of HD 193949, whichis afterwards used in a photoionization model performed with Cloudy thatreproduces the nebular and dust properties for a total mass in the 0.31-0.47M$_{\odot}$ range and a mass of C-rich dust of $\sim$2 $\times10^{-3}$M$_{\odot}$. Adopting a current stellar mass of 0.6 M$_{\odot}$, our modelsuggests an initial mass $\sim$1 M$_\odot$ for HD 193949, consistent with theobservations.

Planetary nebulae with Wolf-Rayet-type central stars -- III. A detailed view of NGC 6905 and its central star