2. speakers
  3. 1213505609

Subwoofer damping

I didn't no whether to post this in the speaker or tech forum, but I'll ask my query.

I have a very large subwoofer which has 2 16 inch drivers. I fired this baby up today after having it in storage for many years. I played a reference recording of Frederick Fennell's Pomp & Pipes. Well I set the crossover pots at 10:00, 6 being the lowest and 5 highest. Everthing was ok till there was some low and I mean low frequency with plenty of dynamics. I could hear the drivers make a girgle sound that came out the 4 vents in the cabinet.

I can't recall if I've heard this before and I'm thinking that I need to add additional damping material. Doe's anybody supply speaker wool anymore? I can't imagine overdriving this thing....I think my house would collapse...so adding more material seems might help. Any speaker tech's with answers would be appreciated.

Roger
wavetrader
wavetrader OP
260 posts
 
Audiokinesis

They are Scanspeak 16's. I don't know the model but the sub was built in about 1992. They have 2 scanpeak vario vents on either side. The box is about 20"Wx48Lx56H. I talked to the designer years ago and he mentioned that they needed more damping material. There were 2 of these made and were used in a resturant/disco-bar. They would litterly shake the whole building like a earthquake. When I had the cabinet sent to my cabinet maker the sub was dissasembled so I don't think enough material was put back in.
wavetrader OP
260 posts
 
AudioK

If you click on my system there is a picture of the sub.
wavetrader OP
260 posts
 
The vents are 4 inch.
wavetrader OP
260 posts
 
Acually I got out a tape and measured the box: 20WX41Lx50H
shadorne's avatar
Ag insider logo xs@2x
shadorne
7,477 posts
 
The box must be a folded horn or bass bin....it is too big for acoustic suspension. The problem with folded horns is the out of band noise from cabinet vibration (two parallel sides along the horn) and issues at sharp angles as you turn corners. You may need to open them up as something may be loose (perhaps glue has dried out and cracked when it was stored or something warped due to humidity/damp).

Bass bins are what would be used in a disco bar...(a type of band pass design)

See this for an explanation
More to discover