I use the line transformers now with my deneke ps2, which provides phantom power, but is not a mic preamp. The line transformers boost the output levels to more match a line level input. THe c1000s are nice, as they don't require phantom power, but rather can be powered by the internal 9v batteries. Most other inexspensive mics that are used for recording (octavas, pulusos, Studio Projects, etc) require phantom power. The line tranformers do not provide this.