Help my preamp sucks in my woofer


I have an Audio Innovations tube preamp about 12 years old. When I turn it on, there is a weird sound in my speakers and my woofers move in at the same time. This has happened with three different amps so I believe its the preamps fault. With A tube amp, the sound was when I shut the preamp off not when I turn it on Now I have a solid state amp which runs in the always on postion all the time and the sound and woofer suck-in happens on turn on???
bbchem
Turn on thump is a common phenomenon with valve amps. The solution: turn your preamp on first, then your power amp. That should fix the problem.
By leaving the power amp on all the time, yes, you are going to hear the turn on and turn-off transient thumps of your older preamp.

Since you indicated that your amp remains turned on all the time you should look for a different preamp with a turn-on, turn-off muting circuit if this bothers you.

The woofers sucking in probably indicates a DC transient pulse... it may not be harmful, but neither is it a good thing.