I've been playing around with winisd, and 4th order band pass elcosures and i have found i can get it peaking at like 35ish Hz. It drops off either side pretty quick, but i was thinking of making it just to hear loud deep bass . This will be done out of pure boredom.
But anyway, what are the advantages of a 4th order band pass over a normal ported enclosure. So far i have found that ported is easier to create a flatter response, but meh, who likes sq anyway . Can anyone point out any other advantages.
I will be using a daily driver box which is ported, but im stumped as to how your can suitably seal up one of the sides, but also make it removable to get the sub out?
Is it still advisable to use loading with the port too?
And finally, are 6th order enclosures worth bothering with? or am i wasting my time completely with band pass.
Sorry for all the ramble
Cheers
Bob
Full Version: 4th order bandpass
I have always liked bandpass boxes the best, if you can get em perfect.
That is the main reason i have stuck to either sealed or ported enclosures.
That is the main reason i have stuck to either sealed or ported enclosures.
bandpasses can really sound like crape
they can also be more efficient, meaning good SPL scores. (part of the reason some cheap subs come in bandpass boxes)
i've only heard one bandpass box that sounded good.
i've heard a few that sounded REALLY verage, but made some noise with small amounts of power.
also the tuning range was pretty narrow, so they only hit between ~45 and 80 Hz they were useless elsewhere.
they can also be more efficient, meaning good SPL scores. (part of the reason some cheap subs come in bandpass boxes)
i've only heard one bandpass box that sounded good.
i've heard a few that sounded REALLY verage, but made some noise with small amounts of power.
also the tuning range was pretty narrow, so they only hit between ~45 and 80 Hz they were useless elsewhere.
Yes, but for SPL you need 1 note, thats it
Hence why bandpass are showing up in street...
Hmmm, bandpass horn, interesting...
Hence why bandpass are showing up in street...
Hmmm, bandpass horn, interesting...
4th order bandpass boxes can work very well for SPL.. For SQ they aren't that great due to their limited bandwidth and higher group delay.. Many of the nice sounding 4th order boxes are usually tuned farily high, so the front port isn't really doing much and they sound a lot like a normal sealed enclosure.. (ignoring horn loaded bandpass enclosures which can sound nice as well as gaining SPL as the group delay is less peaky)
6th order boxes can get similar SPLs, but over a larger bandwidth.. For pure SPL, they don't have any advantage over 4th order as the output from the front and rear ports are out 180 degrees out of phase, so if you tune them close together, you will get cancellation, if you tune them further apart, it will just increase the bandwidth..
I'm not quite sure why you'd want a bandpass box with a big peak at 35hz, as it would sound pretty crappy and 35hz is generally too low to have much benefit as far as outright SPL goes..
[ December 03, 2002, 19:43: Message edited by: Bassaholic ]
6th order boxes can get similar SPLs, but over a larger bandwidth.. For pure SPL, they don't have any advantage over 4th order as the output from the front and rear ports are out 180 degrees out of phase, so if you tune them close together, you will get cancellation, if you tune them further apart, it will just increase the bandwidth..
I'm not quite sure why you'd want a bandpass box with a big peak at 35hz, as it would sound pretty crappy and 35hz is generally too low to have much benefit as far as outright SPL goes..
[ December 03, 2002, 19:43: Message edited by: Bassaholic ]
Can you explain exactly how 4th orders work? And why they are so efficient?
with a 4th order bandpass box, it is a sealed box with an added spring/mass resonant system.. The advantage is the tuneable nature of this extra resonant system..
Anywhere where I can see a graphical explaination? aswell as in words? I sorta know what it does, but need the physics of it
ok, so in a 1st order enclosure speaker produces a given amplitude wave (proportional to the amount of power and efficiency) over one cycle. If you were to delay this signal and build up the energy over a period of time (over a given amount of cycles), when it is released the resulting amplitude will be greater, at the expense of a delay.
[ December 03, 2002, 21:13: Message edited by: Bassaholic ]
[ December 03, 2002, 21:13: Message edited by: Bassaholic ]
QUOTE
Originally posted by Bassaholic:
it is a sealed box with an added spring/mass resonant system
i dont understand that, but it sounds like something i read ages ago.it is a sealed box with an added spring/mass resonant system
do u mean like having 1 sub, but the box has 2 holes in it and in 1 of the holes theres a "fake" sub which is only the cone that can move??? this isn't hooked up 2 anything but does something.. absorbs the vibrations instde or somethin...
is that what a 4th bandpass is??? if not.. what is that thing im talking about??
thx.
sounds like a port (Helmholtz resonantor) to me..
its resonance is determined by the compliance (ie springiness) relationship between the air in the box and the port, and the air mass inside the port
[ December 03, 2002, 22:09: Message edited by: Bassaholic ]
its resonance is determined by the compliance (ie springiness) relationship between the air in the box and the port, and the air mass inside the port
[ December 03, 2002, 22:09: Message edited by: Bassaholic ]
yep that it!
Can you show me any pics of a typical 4th order?
richie, you have no space for a dual 12 bandpass!!! live with it! and i do! hahahahah
i'll get you a bloody pic. here, read and weap!
and before you start asking what the hell it is... that is a cut out of a 4th order bandpass... the subs firing into the side sealed chambers (one sub per sealed chamber), large ported chamber in the middle... this is the box used for 159db in s1-2! secret inside info only for caa members!
[ December 04, 2002, 11:53: Message edited by: rippedskin ]
i'll get you a bloody pic. here, read and weap!
and before you start asking what the hell it is... that is a cut out of a 4th order bandpass... the subs firing into the side sealed chambers (one sub per sealed chamber), large ported chamber in the middle... this is the box used for 159db in s1-2! secret inside info only for caa members!
[ December 04, 2002, 11:53: Message edited by: rippedskin ]
Why is the pink wall at the back shorter than the rest? And why are the side walls double thicknes?
If the subs fire into the sealed chambers, I dont understand how it would go louder than a regular ported box? Wouldnt the pressure/energy in the sealed chambers be wasted?
If the subs fire into the sealed chambers, I dont understand how it would go louder than a regular ported box? Wouldnt the pressure/energy in the sealed chambers be wasted?
what pick wall is shorter... just read the measurements again. side walls are double thickness for strength! i thought you would know that by now, thats where the subs are getting mounted...
it's hard to explain why a bandpass is likely to be louder to someone that obviously has no idea about bandpasses... it just will be louder! and i'll prove it hahahahhahaha
it's hard to explain why a bandpass is likely to be louder to someone that obviously has no idea about bandpasses... it just will be louder! and i'll prove it hahahahhahaha
QUOTE
Originally posted by Bodyjar:
If the subs fire into the sealed chambers, I dont understand how it would go louder than a regular ported box? Wouldnt the pressure/energy in the sealed chambers be wasted?
Not really.. the sealed chambers are smaller so there is less damping on the woofers resonance.. Although I will admit that particular design is a bad example..
If the subs fire into the sealed chambers, I dont understand how it would go louder than a regular ported box? Wouldnt the pressure/energy in the sealed chambers be wasted?
QUOTE
Originally posted by Bassaholic:
[QBAlthough I will admit that particular design is a bad example..[/QB]
bad example? we are in an SPL discussion right??? the box is purely made for SPL...???
[QBAlthough I will admit that particular design is a bad example..[/QB]
I'll let you figure this one out..
Look at the back of the port John, the pink wall there is one thickness too short, will this have an effect on tuning? even though it isnt much?
You can't explain it because you don't know it! I'll believe it when I see you build it
You can't explain it because you don't know it! I'll believe it when I see you build it
The pink wall isn't what I was talking about.. (its probably just a dodgy diagram..)
Since 4th order band-pass boxes get tuned right on the frequency u want it to peak at for your car.. not ~12hz or whatever below... can it also be said that your impedence is rock bottom at your cars note and therefore max power out of your amp also? cool! try load ur amp down with a 4th order
i was thinking of making a bandpass box for my car if i was going into SPL comp. only bad thing is listing to it for eveyday driving would sound stupid
it would be
boom boom boom BBBOOOOOOOOOOOMMMMMMMMMMMM!!!! boom boom
depending on what hz it hits haha but as someone said earlyer. you only need one tone!
it would be
boom boom boom BBBOOOOOOOOOOOMMMMMMMMMMMM!!!! boom boom
depending on what hz it hits haha but as someone said earlyer. you only need one tone!
Since the bandpass box is pretty much a one note wonder, and i only have/can afford 1 sub, my plans were using my current box for every day driving, and the bandpass for spl comps, but it seems that there would be no way of taking the woofer out of the bandpass box, besides wrecking it.
i wouldnt even bother with a bandpass box, just ask any of the pros how many different ones they have made to get their setup right and u will see why.
richie i understand what you are talking about now... that is the space left for the aero part of the port yes it'll take quite a bit of tuning to get right... and it'll probably be a one note wonder. but by changing the port it MAY be ok for daily driving...
QUOTE
Originally posted by CHIEF:
i wouldnt even bother with a bandpass box, just ask any of the pros how many different ones they have made to get their setup right and u will see why.
159.*dB Street 1-2 can't be all bad?!?! hehehe
i wouldnt even bother with a bandpass box, just ask any of the pros how many different ones they have made to get their setup right and u will see why.
not bad at all, still many hours of building and testing, then rebuilding and retesting.
quote:
Originally posted by CHIEF:
[b]not bad at all, still many hours of building and testing, then rebuilding and retesting.
if your using WinISD to design a 4th order bandpass box remmember to compensate the volume the speaker itself into the volume of the actual chamber its going in.
I forgot this and paid the price of an out of tune bandpass box that farts because its 3ltr's off what it should be
only way to repair the problem is to rip it apart and do it again... 1" thick mdf hmm
one piece of advice - measure twice cut once
saves you time and money
I forgot this and paid the price of an out of tune bandpass box that farts because its 3ltr's off what it should be
only way to repair the problem is to rip it apart and do it again... 1" thick mdf hmm
one piece of advice - measure twice cut once
saves you time and money
QUOTE
Originally posted by Rasta:
if your using WinISD to design a 4th order bandpass box remmember to compensate the volume the speaker itself into the volume of the actual chamber its going in.
I forgot this and paid the price of an out of tune bandpass box that farts because its 3ltr's off what it should be
no offence, but that 3L difference won't really make an audible difference, certainly not enough to make an otherwise well designed box, sound bad..
if your using WinISD to design a 4th order bandpass box remmember to compensate the volume the speaker itself into the volume of the actual chamber its going in.
I forgot this and paid the price of an out of tune bandpass box that farts because its 3ltr's off what it should be
I heard that bandpass boxes provide great effeciency. My understanding is any amp (no matter its power output) wouldnt make a huge difference to spl in a bandpass enclosure.
QUOTE
Originally posted by 1337shiznit:
no offence, but that 3L difference won't really make an audible difference, certainly not enough to make an otherwise well designed box, sound bad..[/b]quote:
Originally posted by Rasta:
[b]if your using WinISD to design a 4th order bandpass box remmember to compensate the volume the speaker itself into the volume of the actual chamber its going in.
I forgot this and paid the price of an out of tune bandpass box that farts because its 3ltr's off what it should be
pop some figures into winISD and compare.... 4th orders are very picky about volume sizes, ma sub is very monotonous.. the biatch also farts cause i didnt flare the internal side of the port.
first attempt at 4th order with 2 weeks of research and designing
[ January 06, 2003, 21:15: Message edited by: Rasta ]
QUOTE
Originally posted by Rasta:
pop some figures into winISD and compare.... 4th orders are very picky about volume sizes, ma sub is very monotonous.. the biatch also farts cause i didnt flare the internal side of the port.
first attempt at 4th order with 2 weeks of research and designing
I already know it won't make enough difference, but I popped the numbers into winisd for about 10 different subs and sure enough there was virtually no difference in frequency response with only a 3L change in either chamber. Generally the problem with very efficient bandpass boxes, besides higher group delay is just what the name implies - they only have a limited bandwith hence the monotonous sound.
pop some figures into winISD and compare.... 4th orders are very picky about volume sizes, ma sub is very monotonous.. the biatch also farts cause i didnt flare the internal side of the port.
first attempt at 4th order with 2 weeks of research and designing
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