Acoustic Testing - PAC International Floating Floor

Through the Acoustics and Noise control course offered by Michigan Tech, my team and I were given the opportunity to replicate and investigate the testing process on an acoustic product; floor isolation pads from PAC International. These are designed to suspend and isolate wood flooring in applications such as weight lifting gyms. The objective was to replicate the initial acoustic testing performed by PAC to see if the results would be consistent as an attempt to validate the testing process. This acoustic testing varies from traditional testing by the measurement of velocity data from a variety of accelerometers excited by an impact hammer struck in the corner of the floor . The idea is to compare the velocity data of the wooden platform with that of the concrete base (separated by PAC isolation pads). Through analysis of the data we conclude on the efficacy of the velocity test method to predict SPL reduction.  We are able to convert the velocity data to plottable SPL chart with a reference of 1g (gravity). What we found is that we could not excite the floor (with isolation) to record velocity below the environmental noise floor.
*There were various factors impacting these results, such as elevator operation, HVAC systems, and other building vibrations. 

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Acoustic Treatment - Drum Room

The head of the sound department left us an office, we turned it into a recording space. When emptied, we tested the response of the room with Fuzz Measure, giving us an idea of what we're working with. Surprisingly, the response was fairly tight and flat on it's own, with little bass overhang and reduced modes as compared to other square rooms. The ceiling was lined with a layer insulation, and covered  with periodic Auralex T'Fusor diffusion panels. The absorption panels were constructed with a 2" layer of Rockwool comfort board and a second 2" layer of 703 FRK fiberglass with a foil sheet. This sheet, placed between the comfort board and fiberglass, acts as a diaphragm for additional absorption of low frequencies. Additionally, there was a 2" air gap behind each panel to increase the effective absorptive surface area. The next step was to add the floating floor, constructed out of mass loaded vinyl, sandwiched between plywood, sealed with Green Glue. This was specifically implemented to isolate drum kits from the room. With the installation of the treatment complete, we tested the response of the room again, comparing the results of the bare room. An additional rack and network jacks were added for audio routing to and from the control room.