Dear Forum Members,
I am experiencing quite a few failures of McCauley 6256 18" drivers and changed the drivers to my personal favorites - 2240H. The DJ drives it hard, and I've got him squeezed down a bit with a DBX 2215 with peak stop limiting. The cabinets are homebrew boxes I built 15 years ago, modeled after a box we pulled out of a nightclub retrofit. The chief engineer I worked for at the time said these are good enough and to build three more of them. The JBL 2240's are not lasting any longer.
I just bought Harris BassBox Pro from Parts Express. The box is (outside dimensons) 32" high X 23.5" wide X 20" deep. It has a rectangular vent with the port opening of 5.125" X 15.875" on the lower half of the baffle board, with a total duct length of 13.875".
It seems as if the drivers are over-excurting, and burning up voice coils. There are three of these sub cabinets in a small 25' X 25' dance floor. They are powered by a Mackie 2600. The room is biamped with a homebrew Cerwin-vega box with a 12 and Peavey HT-94 tweeter using a Dayton 3.5K box-ready crossover from PartsExxpress. They work fine as a high-mid, powered by Mackie 1400i amps. Everything is a simple 8 ohm load.
I am running out of ideas and out of money for recones.
Has anybody ever had this problem before?
I read all of your posts, and live for and love my own JBL collection of pieces and parts!!!
Questions:
1. Do I rebuild the baffle board with a different size vents?
if so... what size should it be?
2. Do I look for 4520 scoops w/ 2225s?
3. Do I change to Crown Macro 2400 amps for subs?
4. Do I fire the DJ? ; or teach him how it works?
Please help as my wife, although an incredible understanding strong person, is kind of tired of listening to me talk about Q, free air resonance, box loading and tuning, torn surrounds....
Thank You.
Scott.