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Here's how I see it:

 

A "bandpass" box or n'th order bandpass box, has a very narrow range of frequencies in comparison to a ported or sealed enclosure optimized to the drivers in question. 

 

The greater the n'th order the narrower frequency range and the greater the peak around the frequency the box is tuned to.   Generally they are rather difficult to construct and tuning can sometimes mean getting it wrong and the drivers  going up in smoke.  Whistling is but one example of making your mouth into a "bandpass" box and why you whistle loudest at one particular frequency and not at all at lower frequencies.  

 

I've found a simple ported and well constructed box gives adequate for my particular tastes.   

 

What's going to determine "how hard it will hit": 

 

1) The rated SPL (Sound Pressure Level) of the drivers in question.   Every 3 DB (3 Decibel) increase requires twice the amp power used to the prior sound level.  So in essence the higher rated SPL of a given driver the more efficiently it converts electrical energy to mechanical energy in sound pressure. 

Speakers make either sound or heat. 

 

2) The response curve or "bode plot"of the driver in question and any associated passive crossover components used in the design. 

 

3) The box and how the dimensions of it, any vents if so present, against the cone resonance (Fs) and Thiele Small parameters for the speaker being used.

    

Hypothetically the more drivers one has the greater sound pressure level as increasing the driver count increases the mass of air moved.  Assuming they are all operated in phase and in suitable enclosures.  To get things louder simply move more air.     

 

By far the "hardest hitting'" enclosures are probably very massive (Think 12 feet wide by four feet tall and six feet deep ) horn loaded monsters built by JBL  used in outdoor commercial sound applications.  These things are  very scaled up versions of a horn tweeter but built for bass and lots of it.  In this case there's a LOT of air in the horn cavity of these beasts that hits like a freight train once it gets moving.

  

Understand:  "How Hard it Will hit" depends on your own personal preferences:   It could very easily be you may enjoy a third or forth order bandpass box tuned to about 40 Hz over a ported tuned down to 20.    I would definitely ask around and listen around to what others have done and try to get some idea from there forward. 

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1 hour ago, JohnP said:

Here's how I see it:

 

A "bandpass" box or n'th order bandpass box, has a very narrow range of frequencies in comparison to a ported or sealed enclosure optimized to the drivers in question. 

 

The greater the n'th order the narrower frequency range and the greater the peak around the frequency the box is tuned to.   Generally they are rather difficult to construct and tuning can sometimes mean getting it wrong and the drivers  going up in smoke.  Whistling is but one example of making your mouth into a "bandpass" box and why you whistle loudest at one particular frequency and not at all at lower frequencies.  

 

I've found a simple ported and well constructed box gives adequate for my particular tastes.   

 

What's going to determine "how hard it will hit": 

 

1) The rated SPL (Sound Pressure Level) of the drivers in question.   Every 3 DB (3 Decibel) increase requires twice the amp power used to the prior sound level.  So in essence the higher rated SPL of a given driver the more efficiently it converts electrical energy to mechanical energy in sound pressure. 

Speakers make either sound or heat. 

 

2) The response curve or "bode plot"of the driver in question and any associated passive crossover components used in the design. 

 

3) The box and how the dimensions of it, any vents if so present, against the cone resonance (Fs) and Thiele Small parameters for the speaker being used.

    

Hypothetically the more drivers one has the greater sound pressure level as increasing the driver count increases the mass of air moved.  Assuming they are all operated in phase and in suitable enclosures.  To get things louder simply move more air.     

 

By far the "hardest hitting'" enclosures are probably very massive (Think 12 feet wide by four feet tall and six feet deep ) horn loaded monsters built by JBL  used in outdoor commercial sound applications.  These things are  very scaled up versions of a horn tweeter but built for bass and lots of it.  In this case there's a LOT of air in the horn cavity of these beasts that hits like a freight train once it gets moving.

  

Understand:  "How Hard it Will hit" depends on your own personal preferences:   It could very easily be you may enjoy a third or forth order bandpass box tuned to about 40 Hz over a ported tuned down to 20.    I would definitely ask around and listen around to what others have done and try to get some idea from there forward. 

Loving these responses. I'm learning new things! I hope you respond more often! 

2011 Chevy Silverado under construction

My build log here. Check it out! 

 

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3 hours ago, JohnP said:

Here's how I see it:

 

A "bandpass" box or n'th order bandpass box, has a very narrow range of frequencies in comparison to a ported or sealed enclosure optimized to the drivers in question. 

 

The greater the n'th order the narrower frequency range and the greater the peak around the frequency the box is tuned to.   Generally they are rather difficult to construct and tuning can sometimes mean getting it wrong and the drivers  going up in smoke.  Whistling is but one example of making your mouth into a "bandpass" box and why you whistle loudest at one particular frequency and not at all at lower frequencies.  

 

I've found a simple ported and well constructed box gives adequate for my particular tastes.   

 

What's going to determine "how hard it will hit": 

 

1) The rated SPL (Sound Pressure Level) of the drivers in question.   Every 3 DB (3 Decibel) increase requires twice the amp power used to the prior sound level.  So in essence the higher rated SPL of a given driver the more efficiently it converts electrical energy to mechanical energy in sound pressure. 

Speakers make either sound or heat. 

 

2) The response curve or "bode plot"of the driver in question and any associated passive crossover components used in the design. 

 

3) The box and how the dimensions of it, any vents if so present, against the cone resonance (Fs) and Thiele Small parameters for the speaker being used.

    

Hypothetically the more drivers one has the greater sound pressure level as increasing the driver count increases the mass of air moved.  Assuming they are all operated in phase and in suitable enclosures.  To get things louder simply move more air.     

 

By far the "hardest hitting'" enclosures are probably very massive (Think 12 feet wide by four feet tall and six feet deep ) horn loaded monsters built by JBL  used in outdoor commercial sound applications.  These things are  very scaled up versions of a horn tweeter but built for bass and lots of it.  In this case there's a LOT of air in the horn cavity of these beasts that hits like a freight train once it gets moving.

  

Understand:  "How Hard it Will hit" depends on your own personal preferences:   It could very easily be you may enjoy a third or forth order bandpass box tuned to about 40 Hz over a ported tuned down to 20.    I would definitely ask around and listen around to what others have done and try to get some idea from there forward. 

A 4th order enclosure with a correctly calculated ratio would have a wider bandwidth than any bass reflex (ported) enclosure. And 3db’s can be gained on “the same setup” from going from a sealed enclosure to a bass reflex enclosure. And another 3db’s can be gained from going from a bass reflex enclosure to a band pass enclosure.

:stupid:“How can we help you?”
:guido:
“And don’t forget to tell them that 
the customer isn’t always right.”

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Pretty good article on band pass boxes here:

 

Bandpass Enclosure Characteristics – JL Audio Help Center - Search Articles

 

And this individual does a pretty good job with the box software in terms of frequency response, applied wattage, and cone excursion for sealed, ported, 4th and 6th  bandpass boxes

 

Sealed vs Ported vs Bandpass speaker box/enclosure - YouTube

 

The graph action really starts at around 2:27 .   Watch at 5:56 and pay attention to cone excursion.

 

 

 

 

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BDA951DF-4DE7-4D06-BACC-5BEEA0728C48.thumb.jpeg.9fced018eec476d0e335fb97eb89b743.jpeg
I design enclosures. You don’t understand completely what you are reading. The ratio of a 4th order enclosure determines its bandwidth and if you expand the ratio to generate more spl, you narrow the bandwidth. But if you make the ratio smaller then the bandwidth expands and the spl decreases. 4th order enclosures can be designed to be very musical with a wide bandwidth or really loud on a smaller bandwidth or a happy medium. And just in case you didn’t know, a band pass ratio is the difference in the section’s net volumes.

:stupid:“How can we help you?”
:guido:
“And don’t forget to tell them that 
the customer isn’t always right.”

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Just my humble opinion and observation... 

 

Looking at the entire shared video paying attention to the graphs and discussions for sealed, ported, 4th and 6th order bandpass boxes raises some concerns especially around the time marks in the video mentioned earlier.   Reading the entire JL audio article also raises some construction and tuning issues I think one should be aware of especially if building their own enclosure or buying one in some way, shape, or form.   

 

In any kind of formal or even impromptu engineering there's decisions and trade offs.   Do I want the benefits of increased SPL offered by a bandpass box at the risks involved ?   What happens if something fails and what would be the loss or propensity to repair ?  If someone is building their own box  how can mistakes be corrected ?   Murphy's Law does reign supreme .        

 

How do the various graphs of frequency versus SPL read and what are the graphs of port velocity versus wattage, frequency, cone excursion, and if so available dispersion patterns in two and three dimensions read ?   

 

Bottom line:  Want more sound pressure ?  Move more air.  How to move more air ?  Add more drivers, swap in more efficient drivers,  or leverage the air in however many chambers in the box to move.  All have their risks, rewards, and trade offs.    

 

 

 

  

 

 

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Question, have you ever built, designed or used a 4th order enclosure or 6th order enclosure? And I’m not talking about hearing one of them enclosures on a demo or reading or viewing things off the internet. You seem like an intelligent man, don’t come to a conclusion on something just based on an internet article and a YouTube video that doesn’t even tell you the specs and ratios of the enclosures and possibly some more things you found out via internet. The internet isn’t always true and factual and isn’t the best way to learn some things. Actual experience by designing and. Holding and going through trials and errors is the best way to learn some things. How can you come to a conclusion with such minimal information and just trust an article on the internet and a YouTube video that has 272 likes and 36 dislikes that doesn’t list specs and just shows results. That’s a blind conclusion you are making. Did you know that if you spout of before you know facts then that is foolish.

:stupid:“How can we help you?”
:guido:
“And don’t forget to tell them that 
the customer isn’t always right.”

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@JohnP, Question, have you ever built, designed or used a 4th order enclosure or 6th order enclosure? And I’m not talking about hearing one of them enclosures on a demo or reading or viewing things off the internet. You seem like an intelligent man, don’t come to a conclusion on something just based on an internet article and a YouTube video that doesn’t even tell you the specs and ratios of the enclosures and possibly some more things you found out via internet. The internet isn’t always true and factual and isn’t the best way to learn some things. Actual experience by designing and. Holding and going through trials and errors is the best way to learn some things. How can you come to a conclusion with such minimal information and just trust an article on the internet and a YouTube video that has 272 likes and 36 dislikes that doesn’t list specs and just shows results. That’s a blind conclusion you are making. Did you know that if you spout of before you know facts then that is foolish. Don’t take it the wrong way. I’m not calling you a fool. But you making a blind conclusion is foolish.

:stupid:“How can we help you?”
:guido:
“And don’t forget to tell them that 
the customer isn’t always right.”

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