Strange behavior with a minor change to Citation 7.4 subs

[ParleyW]

I picked up a pair of Harmon Citation 7.4 passive subs for a song. I had the woofers restored by Matt at Utah Reconing (801-419-3099). He even touched up the paint on the frame and magnet assembly. Look brand new.

What was odd about these is the lack of a gasket. I’ve seen the same on the JBL L series woofers. So when the time came to put them back in I added a foam gasket to one, left the other without. After some testing, the sub with the gasket had far more punch, deeper tone, it improved the performance tremendously.

I dont understand why this would have made that big of a change to the sound. The had a very tight fit without them….or at least, I thought the did. I may post this out on the Heritage forum as well.

 

[Pogre]

Those cones look pretty good!

As far as the differences you're hearing, if you're comparing one sub to another and they're in different locations they will for sure perform differently even if perfectly identical. Your room and placement are in charge of your bass response. To do a proper apples to apples comparison you really need to have a level playing field. Adding a gasket likely shouldn't have any significant effect unless it changed the internal cabinet volume or there's a leak.

 

[ParleyW]

Those cones look pretty good!

As far as the differences you're hearing, if you're comparing one sub to another and they're in different locations they will for sure perform differently even if perfectly identical. Your room and placement are in charge of your bass response. To do a proper apples to apples comparison you really need to have a level playing field. Adding a gasket likely shouldn't have any significant effect unless it changed the internal cabinet volume or there's a leak.

Thx for that. I swapped them so the positions were the same. I’ve tested the cabinet for level with a level. There is a very slight warp in the face so a leak was likely unless the screws were torqued down.