6th order bandpass design advice.

[Triticum Agricolam]

I'm guessing the blue line is the rear chamber.

My box will be 6' rear 28hz and 9' front 55hz.

So from what the graph is showing. I wont be burping at 40hz anymore with the new box?

The blue line was with a 3 cu ft rear chamber and 1.25 cu ft front chamber.

What subs and amp are you going to be using? Its a lot easier to get loud at higher frequencies, this is why the lower tuned chamber is generally larger, so as to keep up with the front chamber output. However cabin gain is going to boost low frequency output significantly, so that should be considered when coming up with a design as well.

[Smoove]

2 SP4 15's and a Sundown scv6k @ .5

[bassfreak85]

Doug built a parallel-tuned 6th order, which is definitely the easier of the two to get right (the other being a series-tuned 6th order). Parallel-tuned boxes are larger though.

WinISD can model that style of box and that (or other simulation software) is probably going to give you the best chance of success right off the batt. As far as subs go, any sub that works well in a ported box should work decently in a parallel-tuned 6th order BP. Since the chambers are separate, tuning them is exactly like tuning a regular port box (unlike series-tuned BP6 boxes). There are no standard "ratios" you just have to size the chambers independently.

2 SP4 15's and a Sundown scv6k @ .5

typically i like to keep the rear chamber close to what would be required for a ported alignment and the front chamber ruffly half that depending on how wide you want the bandwidth and how the shape of the curve is. the wider the bandwidth the less output you have and typicality the peakier it is around tuning.. fe exception are if you want a ultra low tuning for extended lowend you must use a larger box and you limit power-handling and group delay is way high. this creates alot of output around tuning and a dip in the pass band until the second tuning. another issue is phasing. which is the tricky part IMO. both waves are 180 degrees out of phase so keep that in mind when you build the box. you typically want to keep the ports on the same plane which enough distance in the rear or front wave to be within 50% of the 1/4 wavelength to get any real coupling and increase output over yor typical 4th order alignment..

i can help you design something but ive charged in hte past and it would only be fair to do so again.

[Triticum Agricolam]

2 SP4 15's and a Sundown scv6k @ .5

Here is the frequency response for those box specs:

And here it is with roughly approximated cabin gain for a standard size SUV:

With cabin gain it look pretty decent, you will still probably peak up pretty high, but you have a nice wide bandwidth from the mid 20s all the way up to 60 Hz or so.

[Smoove]

2 SP4 15's and a Sundown scv6k @ .5

Here is the frequency response for those box specs:

And here it is with roughly approximated cabin gain for a standard size SUV:

With cabin gain it look pretty decent, you will still probably peak up pretty high, but you have a nice wide bandwidth from the mid 20s all the way up to 60 Hz or so.

I like the way that looks

[Smoove]

Hammer time

[Smoove]

Doug built a parallel-tuned 6th order, which is definitely the easier of the two to get right (the other being a series-tuned 6th order). Parallel-tuned boxes are larger though.

WinISD can model that style of box and that (or other simulation software) is probably going to give you the best chance of success right off the batt. As far as subs go, any sub that works well in a ported box should work decently in a parallel-tuned 6th order BP. Since the chambers are separate, tuning them is exactly like tuning a regular port box (unlike series-tuned BP6 boxes). There are no standard "ratios" you just have to size the chambers independently.

2 SP4 15's and a Sundown scv6k @ .5

typically i like to keep the rear chamber close to what would be required for a ported alignment and the front chamber ruffly half that depending on how wide you want the bandwidth and how the shape of the curve is. the wider the bandwidth the less output you have and typicality the peakier it is around tuning.. fe exception are if you want a ultra low tuning for extended lowend you must use a larger box and you limit power-handling and group delay is way high. this creates alot of output around tuning and a dip in the pass band until the second tuning. another issue is phasing. which is the tricky part IMO. both waves are 180 degrees out of phase so keep that in mind when you build the box. you typically want to keep the ports on the same plane which enough distance in the rear or front wave to be within 50% of the 1/4 wavelength to get any real coupling and increase output over yor typical 4th order alignment..

i can help you design something but ive charged in hte past and it would only be fair to do so again.

Bassfreak85, I have a good design. Just wanted to understand how the design I have works a little more.

[bassfreak85]

sorry

[bassfreak85]

sorry fellas..

what you came up with? box size and tune?

Trit- are you modeling with parameters shifts? say 10-15% for QE and FS that is typical or your just doing baseline?

[Triticum Agricolam]

sorry fellas..

what you came up with? box size and tune?

Trit- are you modeling with parameters shifts? say 10-15% for QE and FS that is typical or your just doing baseline?

I'm just modeling with the baseline parameters.

I'm sure inductance is going to rob these subs of some motor force, but its more difficult to predict.