A fluid delivery system includes a first pressure sensor disposed on or near a spray gun and configured to monitor a first fluid, and a second pressure sensor disposed on or near the spray gun and configured to monitor a second fluid. The fluid delivery system further includes control system comprising a processor configured to receive a first signal from the first pressure sensor and to receive a second signal from the second pressure sensor. The processor is further configured to derive a pressure difference between the first and the second pressure sensor representative of a fluid pressure difference between the first fluid and the second fluid and to control one or more pumps to obtain a desired pressure difference.