"The BP4 still reaches a higher SPL even though the BR can take 50 volts."
Not at 30Hz according to Art.
The point I was making is that at 30Hz he was comparing a ported rear chamber to a sealed rear chamber, hence the apples and oranges remark.
Rob.
Not at 30Hz according to Art.
The point I was making is that at 30Hz he was comparing a ported rear chamber to a sealed rear chamber, hence the apples and oranges remark.
Rob.
So I was trying to find the issue of either Car Audio & Electronics or Car Stereo Review where an Earthquake bandpass enclosure crushed the other enclosures in a comparison test. I came across this passive radiator system while searching.
I couldn't help myself after last night's debate 🤣. I'm Black, so I could care less who wins. Abraham Lincoln is the only president that did anything positive for my people.
I couldn't help myself after last night's debate 🤣. I'm Black, so I could care less who wins. Abraham Lincoln is the only president that did anything positive for my people.
The BR does not need as much EQ.
Grills seem to be optional for many
Every design has it's excursion limitations.
If efficiency was a concern, we would be comparing larger cabinets.
You're right guy! Because we are using a car audio driver, I've been thinking car audio instead of home audio.
Thanks for the interesting discussion and comparison; those sims are useful to see. Yes this is very definitely about home audio, not car audio, so the restrictions and requirements are a bit different.
The LAB12 seems quite versatile and can be used in car audio, but it isn't specifically a car audio driver. First and foremost, it was designed for use in reasonably large horn-loaded enclosures. So probably that would be optimum for it, though it can do well in other boxes, too. This versatility is one of the things that drew me to it. Though mine is a slight variant (the FAB12), I think they are largely interchangeable.
The LAB12 seems quite versatile and can be used in car audio, but it isn't specifically a car audio driver. First and foremost, it was designed for use in reasonably large horn-loaded enclosures. So probably that would be optimum for it, though it can do well in other boxes, too. This versatility is one of the things that drew me to it. Though mine is a slight variant (the FAB12), I think they are largely interchangeable.
It occurred to me that a simple chamber, with absorbent lining and an offset port, could at least help to attenuate any high frequencies from radiating directly out. If the port was large and short it wouldn't have a noticeable affect on tuning, so the chamber sizes could remain small, much like a simple sealed design.
A bit of modelling suggests that a port that is about 1/3rd of SD and 18mm long (the thickness of some ply sheet) doesn't affect tuning or cabinet size much, and wouldn't suffer from LF pipe resonances or significant airspeed. In the frequency response it still introduces a peak above the crossover point and then steeper roll-off towards high frequencies (that latter might be vaguely useful), though it doesn't extend or increase the lower frequencies.
(so the effects on FR are all above the intended subwoofer range)
So i don't know if this could legitimately be called a bandpass design, but it might still offer at least some of the benefits that I wanted. Another bonus is that it would still hide the driver; the port could even be down-firing (without needing the driver to be oriented horizontally). It might be worth it for that alone, in my case.
A bit of modelling suggests that a port that is about 1/3rd of SD and 18mm long (the thickness of some ply sheet) doesn't affect tuning or cabinet size much, and wouldn't suffer from LF pipe resonances or significant airspeed. In the frequency response it still introduces a peak above the crossover point and then steeper roll-off towards high frequencies (that latter might be vaguely useful), though it doesn't extend or increase the lower frequencies.
(so the effects on FR are all above the intended subwoofer range)
So i don't know if this could legitimately be called a bandpass design, but it might still offer at least some of the benefits that I wanted. Another bonus is that it would still hide the driver; the port could even be down-firing (without needing the driver to be oriented horizontally). It might be worth it for that alone, in my case.
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