activated space
 origins  david cunningham
IKON - maintenance and problem solving

Switching off and on.

Having seen how the equipment had heated up after an overnight run I now think it would be better to switch off completely at night.  Probably simplest to use the mains switch.

An option is to switch off each amp and the two gates individually, leaving the mixer powered so that the mics remain powered, less likely to be affected by humidity and temperature.

This means the system must be switched on at least an hour before the gallery opens every day so that it stabilises.

Ideally the Gallery 4 system should not be run with the doors closed but I suppose this is unavoidable in the mornings.  Closed doors create more high harmonics and I haven't had much opportunity to run the current settings with the doors closed.  If this causes sustained piercing high frequency noise then I suggest never running the system with doors closed.


There are two gates both using channel 1 only in the cabinet.  Top one is Gallery 4 , bottom is 6.
Threshold - this is the setting that effectively controls the volume of the installations.  Anti clockwise opens it and allows more noise in the space before cutting out.  This will make the feedback louder.  Clockwise will reduce the volume in the room at which the gate cuts in.  I don't recommend making it any louder than the current setting.

problem - uncontrollable high frequency feedback:
check mic position
is there anything different in the room?
check settings on equipment

problem - low frequency noise:
is there anything different in the room?
is there anything working loose in the cabinet and causing mains or earth hum?
check settings on equipment

problem - loss of signal:
switch off at mains for 20 sec, then back on.
are all the speakers active?
There is a mini jack plugged into the mixer tape input - playing a CD or something through this will send a signal to all speakers to test that part of the system.  Press the switch marked 2TK TO MIX just above the mixer output faders to activate this cable.  Remember to turn it off afterwards as the open end of the mini-jack could touch something in the cabinet and cause hum.

Are the gates active?  If so, and if all speakers are active try joggling the jack cables at the back of the gates or the jacks going into the mixer.

I suggest getting an aerosol switch cleaner (AF spray or similar) and spraying it into the switches and rear sockets on the gates to lessen the possibility of intermittent contacts happening.

problem - general noise, crackling, hissing:
If it is in one gallery only, switch off and spray the mic with AF spray.  Leave a few minutes and switch on.  If this happens and this is the solution it will be best to leave the mics (and mixer) powered up (see below).

If this is not the solution it may be a dodgy connection somewhere - but at worst case a faulty amp.  Solution is replacement, an interim solution is to turn off the offending amp and try and run that gallery from one set of speakers.  Turn up the mixer output on that channel and see what happens.  It may be acceptable.

If it is in both galleries there may be some problem with the mixer or its power supply.  Check connections but the likely  solution is probably replacement.  (After Mailbox we will have a spare mixer).