In Reply to: Altec Lansing Voice of the Theatre? posted by AndyGrandy on March 23, 2007 at 10:43:04:
I sealed off the upper chamber with a plywood baffle. The new front baffle is 3/4 ply, bolted on using T-nuts. The available volume in the bottom is probably not enough (L.T. 8 ft^3) so I stuffed it with 4 pounds of polyfil. I tuned the bass to the low 30's using a 72 sq in port that is 18 inch long. I measured the impedance with and with out polyfil and the tuning did not change much. However with polyfil the shape of the impedance curve did flatten out at the bottom. If I can figure out how to upload the Excel plot of impedance I will do so.Jim N
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- JBL 2245 in 828 cab - jnorv 09:08:34 03/24/07 (10)
- Re: JBL 2245 in 828 cab - GM 12:44:15 03/25/07 (8)
- After reading the tapped horn from above - jnorv 14:09:47 03/25/07 (7)
- Re: After reading the tapped horn from above - GM 14:19:04 03/25/07 (6)
- I might just have to try that. - jnorv 16:19:14 03/25/07 (5)
- Re: I might just have to try that. - GM 22:12:36 03/25/07 (4)
- Re: I might just have to try that. - AndyGrandy 09:03:35 04/01/07 (3)
- Re: I might just have to try that. - GM 14:51:49 04/01/07 (0)
- When you install a sub in the 828 cab, - jnorv 11:06:36 04/01/07 (1)
- Re: When you install a sub in the 828 cab, - andygrandy 16:31:48 04/23/07 (0)
- Re: JBL 2245 in 828 cab - djn 17:01:47 03/24/07 (0)