In this paper, extensive experimental results on broad-band double cladding Er3+–Yb3+ co-doped superfluorescent fiber sources (SFSs), characterizing their output power, mean wavelength, and bandwidth (BW) stability with variations of pump power, pump wavelength, and fiber temperature, have been reported. For a 55-cm fiber, SFS power from 3.7755 (maximum BW condition of more than 80nm) to 9.1837mW (maximum power condition, BW is about 34nm) has been achieved. The SFS mean wavelength dependence on pump wavelength is highly pump temperature sensitive, and can be reduced to zero in a chosen pump temperature field. The intrinsic variation of the SFS mean wavelength λm with fiber temperature is also measured, and a linear variation from 15 to 45°C with a slop of −0.053nm/°C for Lf=100cm and −0.04nm/°C for Lf=55cm is found.