The infiltration and growth (IG) process is an effective method for the preparation of single-grain REBa2Cu3O7-x (RE-123) bulk superconductors with finely dispersed RE2BaCuO5 (RE-211) particles, compared with the conventional melt growth (MG) technique. However, this process is more complicated and time-consuming because three kinds of precursor powders, involving RE-211, RE-123 and BaCuO2, have to be prepared for the IG process. Based on the regular liquid source composed of RE-123 and Ba3Cu5O8, in this paper, different new liquid sources were developed for simplifying the IG process. And the GdBa2Cu3O7-x (Gd-123) single grains have been successfully prepared using these liquid sources. The morphology, microstructure and levitation force of the Gd-123 superconducting grains have also been investigated. The results indicate that the new liquid sources can be used to simplify the process flow, reduce the cost and advance the efficiency during the fabrication of single-grain Gd-123 superconductors, because only two precursor powders (GdBaCuO5 and BaCuO2) are needed to prepare for the whole process flow. (C) 2011 Elsevier B.V. All rights reserved.