A North American Automotive OEM desired to develop an acoustic transmission loss (TL) test bench that would allow to test a) entire exhaust system and b) down to 20Hz. Sound Answers worked with Bruel & Kjaer, to develop such a system for using the B&K Type 4206 Impedance Tube as a starting point, SA designed and fabricated a Very Low Frequency Sound Source with higher SPL output to allow for the entire exhaust system testing and with good frequency response down to 20Hz. In addition, SA developed and fabricated the components required to transition from the test elements to the standard 100mm and 29mm tube diameters of the B&K Tube along with a pair of termination elements of sufficiently varied impedances to facilitate testing using the so-called 2-load termination method. As a part of the development process, the fabricated system was validated using a simple expansion muffler as a test element. At the conclusion of testing the OEM was trained in the operation of the test stand, and now is able to perform TL measurements in a self-contained setting.