[NJARC] 116X back cabinet cover?

[sgt88 at atlanticbb.net]

It's been mentioned by a few folks that there was? a back cover on the radio 
cabinet to 'work' with the side 'auxiliary' speakers.

The Nash patent # D101063 shows no such back cover.

Nor do I see any holes to suggest that mine had a back cover.

Sooooooo...it seems like acoustic pressure generated by the main speaker is 
ruled out.

The only other means to activate the side speakers is via mechanical 
vibration of the cabinet facia.

This method is highly plausible...and demonstated by placing a vibration 
object onto a "large" - preferably flat surface....like touching an electric 
shaver to such flat plate...one will hear a louder sound.

Also, human hearing in not accomplished via only pressure onto the ear 
DRUM...there is also head BONE ( vibration ) conduction to the 
cochlea...it's common practice to put a vibrating tuning fork - either 256Hz 
or 512Hz - in contact with the skull...( Weber test )...which helps assess 
the cause of hearing loss.

If I could get my hands on a sound level meter I could do some testing on 
this.

Steve T.