McDonalds BoomBox - We're Lovin It!

The purpose of our investigation was to determine whether it would be possible to increase the sound pressure level (SPL) produced by a smartphone inserted into the McDonalds BoomBox. Several aspects of the BoomBox were examined to determine if further improvements could be achieved. Various prototypes were designed and experiments were conducted in which SPLs were measured and recorded for each prototype.
There were 2 main prototypes considered:

  1.  designs where minimal modification were considered in case the client wanted to maintain the original aesthetic appeal,
     
  2.  designs where one speaker was removed.

For each prototype, we took measurements 15 cm away from the horn that encapsulated the phone speaker along the central axis.  Experiments were conducted in noisy environments since the purpose of the McDonalds BoomBox is to be used in public.

SpectrogramAnot.png

This is a spectrogram of a song that was played at the CBC during an interview. On the left under "Without BoomBox" we see the spectral analysis as a function of time. On the right under "With McDonalds BoomBox" is the spectrogram of the song when the phone was inserted into the BoomBox. Notice that the colours on the right are much brighter and more saturated. This means that the SPL associated at those frequency components is higher (i.e., louder)

 

 Our report along with our experimental results and analysis is posted below.


 

Our team also developed an AR app using @UE4 so that the sound transmitted from the speakers could be visualized by holding a smartphone over the BoomBox.