Dirte Dave
CarAudio.com Newbie
Hey ya'll, I'm working on a 8th order bandpass design for my bosses 1965 Impala SS, and I'm having trouble making sense of the proper tuning for the individual chambers. The reason I was going with an 8th order, is mainly because I only have one place I can port the enclosure into the cabin, and that is through the rear seat speaker grill. Also, I'm wanting it to be as musical as possible, not dig real low, and keep the trunk rattles to a minimum. The vehicle owner isn't big on bass at all, so with that said, I'm trying to utilize the trunk area directly behind the rear seat, in front of the spare tire area, that area he doesn't use, however, I can't cut the rear deck up for ports, or even speakers for that matter. So I figured an 8th order would put me right where I need to be. Fingers crossed.....
The speakers I'm planning on using are, 2- JL Audio 6w3v3-4's, one on each side of the trunk, with a shared 4" port in the center chamber, ported behind the factory Impala speaker grill. I've included pics to help reference what I'm working with. One of which, is the basic concept {theory} design that I think will work, but I need help. My specific questions pertain to, which chamber gets tuned high/low, which airspace specs should I use, can slot ports and round ports be used together, how do I calculate the airspace for the center chamber, and will this design completely cancel out, or actually be a homerun 8th order?
I figured, if the enclosure I design, can be tuned internally to say 30hz on the low side, and say 70hz on the high side, then I would tune the center chamber (with the 4" round port) to say 50hz, ultimately widening the bandwidth, and possibly reducing any dips in the freq response as well. JL has the sealed airspace listed at 0.15cf, and the ported airspace listed at 0.25cf per sub. Yes, tiny I know, which is why I assumed these subs would work for what I'm trying to accomplish. I played around with WINisd for my original idea, which was a 4th order bandpass, however, it seamed too peaky for my liking. The vehicle owner (my boss) listens to alot of heavy metal, rock, or jazz/blues, so I was shooting for a wide bandwidth that could be musical for anything he wanted to listen to. Also, the front stage consists of 2 Focal Access 4" coaxials in the dash center speaker location, and 2 Focal Access 5.25" drivers (midbass) in the kick panel locations (which might get upgraded to 6.5" drivers), the amp will likely be an Audiocontrol 5-channel amp, with a RetroSounds 740 in the dash. No dsp for now either, I'm just limited with what I can do.
I appreciate any help and knowledge thrown my way! I haven't found an enclosure calculator that works for complex 8th order designs, so any leads on that would be greatly appreciated as well. Thanks to all who read this short novel, and hopefully someone can easily toss some ideas my way to help out. Thanks y'all.
The speakers I'm planning on using are, 2- JL Audio 6w3v3-4's, one on each side of the trunk, with a shared 4" port in the center chamber, ported behind the factory Impala speaker grill. I've included pics to help reference what I'm working with. One of which, is the basic concept {theory} design that I think will work, but I need help. My specific questions pertain to, which chamber gets tuned high/low, which airspace specs should I use, can slot ports and round ports be used together, how do I calculate the airspace for the center chamber, and will this design completely cancel out, or actually be a homerun 8th order?
I figured, if the enclosure I design, can be tuned internally to say 30hz on the low side, and say 70hz on the high side, then I would tune the center chamber (with the 4" round port) to say 50hz, ultimately widening the bandwidth, and possibly reducing any dips in the freq response as well. JL has the sealed airspace listed at 0.15cf, and the ported airspace listed at 0.25cf per sub. Yes, tiny I know, which is why I assumed these subs would work for what I'm trying to accomplish. I played around with WINisd for my original idea, which was a 4th order bandpass, however, it seamed too peaky for my liking. The vehicle owner (my boss) listens to alot of heavy metal, rock, or jazz/blues, so I was shooting for a wide bandwidth that could be musical for anything he wanted to listen to. Also, the front stage consists of 2 Focal Access 4" coaxials in the dash center speaker location, and 2 Focal Access 5.25" drivers (midbass) in the kick panel locations (which might get upgraded to 6.5" drivers), the amp will likely be an Audiocontrol 5-channel amp, with a RetroSounds 740 in the dash. No dsp for now either, I'm just limited with what I can do.
I appreciate any help and knowledge thrown my way! I haven't found an enclosure calculator that works for complex 8th order designs, so any leads on that would be greatly appreciated as well. Thanks to all who read this short novel, and hopefully someone can easily toss some ideas my way to help out. Thanks y'all.
