View Full Version : Powered sub-woofer signal drop out

08-06-2016, 12:59 AM
I have several 5.1 and 5.2 channel JBL systems in my home. Some are running from a satellite TV cable box and others are running directly from a CD. All of these are connected to various JBL sub-woofers, a few JBL 18"erz, and one sub-woofer running a 2206. These are powered by Dayton plate amps - typically 1000 watts at 8 ohms, or from Crown bridged power amps.

I have several newer and older high end receivers (Denon, Oynko), and one pre-amplifier (Adcom). I have switched receivers, switched CD players, switched JBL sub-woofer, switched plate amplifiers and THEY ALL DO THE SAME THING.

That would be, when played at normal or lower volumes, the sub-woofer signal periodically drops out completely. Then, if I turn the volume up to a loud level, the sub-woofer signal comes back, however. Adjusting the sub-woofer volume up to full tilt relative to the other 5 channels in the receivers or pre-amp does help reduce the occasional signal drop out but it still happens.


Why does the sub-woofer signal drop out and is there any way to stop it?:confused:

Don C
08-06-2016, 07:37 AM
It turns off because it is designed to turn itself off when there is no audio signal present. This feature saves the user from having to reach around to the back and turn it on and off.

08-06-2016, 07:56 AM

so is the turn off bass signal feature, (1) a design function of the receivers, or (2) a design feature of the sub-woofer amplifiers? IS THERE ANYWAY TO TURN OFF THE TURN OFF FEATURE?


Ed Zeppeli
08-06-2016, 08:18 AM
Some powered subs have a switch for off/standby/on. Setting it to 'on' should alleviate the issue. Also, maybe try turning up the volume on the sub and turning down the output on the receiver to get the levels you want.

Good luck,


08-06-2016, 10:18 AM
Actually, turning UP the sub output level on the AVR is the thing to try. Lower the sub's gain to compensate.

Ed Zeppeli
08-06-2016, 04:32 PM
Actually, turning UP the sub output level on the AVR is the thing to try. Lower the sub's gain to compensate.

Good catch. Thanks. Sending it a stronger signal makes the most sense.