Audio Public Address Sound System.

Mornin' All,

                    I need some advice please.


Imagine a portable sound system as used by travelling musicians, rock guitarists or others with electric instruments. There will be a large mixing desk, and amplifier and speakers. All is well if the musicians with electric instruments only plug their 1/4 inch jack plugs into their instruments when the mixer sliders are down (off) so as not to cause a big pop or bang through the speakers. Sometimes though the jack plugs are unplugged from the instruments when the mixer sliders are up (on) and a terrible sound results from the speakers.


Is there a "magic box" that can be inserted in line with the audio leads from the instruments to the mixer that AUTOMATICALLY prevents this unwanted loud noise problem?


Thanks,


Z.