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Turn On/Off Thump
Turn on thump can vary from a slight pop to a mind shattering, teeth rattling BOOM! This thump is caused by the audio circuitry stabilizing when power is applied. Most amplifiers and source units have muting circuitry that lasts a couple of seconds to allow these fluctuations to subside before passing a signal. However, if the amplifier un-mutes before the source unit or any other accessory, you better watch out. Here are some things to try if you have turn on thump.
1. Verify that the amp has a good audio ground reference. (See rule 6 of the Ten Commandments of noise free installation.)
2. Don't install the system so the amplifiers can be switched on when the source unit is turned off.
3. If you still have thump, add a turn on delay module in line with the remote turn on wire to the amp.
4. This concludes the section on turn on thump.