Is it normal for the woofer to move in/out slowly


My only tubed piece is the pre-amp. It is the only piece I turn off when not in use. I noticed that when I turn it off the woofers on my speakers move in and out rather slowly while I hear what I assume are the tubes discharging.

Is that normal and more importantly can it cause damage to the speakers?

Thanks
bokfudo
It sounds like it is OK since the woofers are not driven to their limit and they move slowly. I wish I could leave the tubed pre on all the time but like a light bulb, that would reduce the life of the tubes.

Thanks for the answers!
Here's a question I have concerning this. What would damage the tubes more, surge from turning pre-amp on and off repeatedly or leaving pre-amp on most of the time?
Rja, thats a good question. Have no answer, however, there have been several discussions about if leaving the pre on is better than off. Based on my point of view most don't know the answer and some will offer some elaborate technical reason one way or other, its all pure speculation. Like I said I turn my on and off between listening sessions and have been doing this for years with no negative effect. I have used the same set of 6sn7 tubes over the years.
Rja also brings up a good point, repeated surges from frequent turning on I guess will affect tube life as well. May be the best compromise is to turn the pre on once a day and off for bed time :-)

Cheers
I don't think it would do any harm to the woofers.

My practice is that I always turn the pre amp on first and then the power amps. When turning them off, I turn the amps off first and then the pre amp. That way, nothing affects the woofers.

I learned a lesson a few years ago. I got a tube pre and a SS amps. When I turned off the pre amp first, a surge went to the amps and blew the fuse and some other things in the input stage. I ended up sending the amps back to the factory to repair.