Both those enclosures are BP6S'.
The 2nd enclosure will act like a BP6P due to the low port is right at the high port mouth.
BP6S = TH function.
BP6P = CH function.
BP6P = Nd function with Vrc/Lrc & Ap/Lpt.
BP6P = OD function with Vrc/Lrc & Ap/Lpt.
-3db@23hz, 100msGD@tuning, 25ms@upper resonance after filters (likely measure much lower irl). measurements are at xmax 5.38kw. believe it or not this sub can handle it for a short time. certainly for ht use, np. i traded the vxf for the sundown u v1. it measures about the same but it has better voice coils, more bl, and a stronger cone. park this monster behind your lp and it might make you jump.
This one is similar but has higher Port velocity which is not good for sq but would make for a windy experience in my truck. 33m/s @ 25hz with a 14in port. im certain this would float shirts and flex a windshield. that port would poke out perfectly over my center console.
This one is similar but has higher Port velocity which is not good for sq but would make for a windy experience in my truck. 33m/s @ 25hz with a 14in port. im certain this would float shirts and flex a windshield. that port would poke out perfectly over my center console.
Does an undersized port that gets ‘windy’ (turbulent) translate into ‘windy’ out in the vehicles cabin or would ‘pressure’ at low frequencies be the actual mechanism? So a ‘bigger/longer ‘ non turbulent port ends up creating more of this ‘wind’ when you’re sitting near an open window ?
im certain pressure is part of it. i think mostly velocity and flow. like waterjet vs sump pump hose. now combine the two and you get firehose. im sure pressure is a major part of the equation but id be lying if i said i understood. longer wavelengths are necessary to create the effect. however you cant just play low frequencies and expect it to work. many speakers can play 20hz but few of them can generate wind. bandpass seems to be great at this, thats why almost all of the vehicles that do hair tricks are 6th order bandpass. they move the most air the fastest with the biggest port. the bp8s model moves even more air at higher speeds than the 6th order. does that mean higher order is better for this? idk. i would have to build it to find out!
series tuned qw pipe sure stirs up some velocity @ exit. (I tried to post the video instead but it won’t let me). It’s just a pair of 4” 🍄
I wonder if you tune your second resonator closer(lower) to the fundametal if you’ll Get mOre of this sort of thing ? It lower so maybe by default it just gets even ‘windier’ from more violent wavelegths as you said
I wonder if you tune your second resonator closer(lower) to the fundametal if you’ll Get mOre of this sort of thing ? It lower so maybe by default it just gets even ‘windier’ from more violent wavelegths as you said
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heres what im guessing to be a bp6s inside a trunk with 2 6.5 woofers. Youtube Video
And heres the woofer i have Youtube video
Actually both of those are u series woofers. only thing is hes using subsonics which are fine but not really musical.
And heres the woofer i have Youtube video
Actually both of those are u series woofers. only thing is hes using subsonics which are fine but not really musical.
That’s a super low tuned bass reflex with a flare at the end of the port dumping into the back of the trunk so it’s acting like an additional series chamber section .?
I watched a couple more of his videos. He loaded the same enclosure into a station wagon and was able to do the same thing. Maybe its an aperiodic bi-chamber. Still, I dont see how such small cone area is possible to do such a thing. Splicing the video would be an easier feat.
I'd choose the 1st model. Love the enclosure design!
I'd adjust the model so the peak is at least at 80hz or above. You definitely want a downward response from the low pass filter frequency in a car audio environment. Cabin gain is a M0F0!
So DMB's latest HR updates provide output data in the Loudspeaker Wizard title bar?
This enclosure is not a BP6 design of any kind (series or parallel). Looks to me as being a BR enclosure, but I cannot see the other driver or port. Still impressive for 2 x 6.5's
I had 4 x 6.5's in a BP4 in a 1996 Ford Ranger SuperCab. The enclosure is in my son's home theater system.
You could say that.
A sealed enclosure in a trunk with a window open could be considered a BP4 system.
A BR enclosure in a trunk with a window open could be considered a BP6S system.
A BP4 enclosure in a trunk with a window open could be considered a BP8S system.
A BP6S enclosure in a trunk with a window open could be considered a BP10SS system.
A BP6P enclosure in a trunk with a window open could be considered a BP10PS system.
The only problem with those considerations is measurements are taking inside the vehicle instead of outside the vehicle.
Now, would orders get added based on how the trunk is vented in the cabin? In my Solara and Crown Vic, I removed the rear deck speakers so the bass can easily vent into the cabin. The setup prevents the trunklid from trying to jump off the hinges and trunk rattle.
In 1995, I rebuilt the rear deck out of my 1983 Grand Marquis with 0.75" MDF, Blaupunkt 5.25" component plates, and 2 large square holes from the rear deck bracing. Before the rebuild, I had the stock deck with the Blaupunkts and trunklid tried to separate from the hinges with 4 x 15's in an isobaric BP4.
I wish I had pics of the 83 MGM.
Note the factory subwoofer opening on the CV. I think that hole helped with trunk venting when the car still had the factory 6x8's and the Solara's BP4 enclosure.
Not much ‘wind ‘ or ‘resonating’ low frequencies coming out of a 4th order bandpass type of box unless it was tuned into the dirt and a massive one note wonder spike? Just an SPL beast , with an absurdly small bandwidth?
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Correct. My BP4's are always tuned for music and not SPL. For a vehicle, you want a 60-70hz tune. An in car (0.5pi) BP4 response should equal at least a half octave below and above the tuning frequency.
If the BP4 tune = 60hz,
Then the half octave below tune = 30hz,
And the half octave above tune = 60hz.
A 60hz BP4 should have a 30-90hz bandwidth (-3dB).
I wonder why they don't have the driver and port on the same side of the enclosure for that particular situation. For trunk installs, the best performance is firing towards the bumper unless you have all the output going through the rear deck.
I still remember hearing an 80's Saab 900 Turbo with 2 BR 18's. It was the best sounding car to me until I heard a BP4 enclosure in a car. I heard a single BP4 JL Audio 10 in a Honda CRX. The output was ridiculous!
Consider the trunk as a series resonator like awkward shaped versions of the ‘roar’ …. Everything is sealed up tight with construction adhesives and the music played is intentionally rebassed for his 18-20 hz demos(and YouTube/Facebook videos )
He uses a few different TL/big vented reflex shapes with the same basic architecture to ‘float’ a pillow case in the window and get to 148dB or so with two ‘small’ drivers (with huge X mech).
It’s all noise, not useful for music . Like a science experiment. Just for fun.
I guess there’s more here(if you can tolerate these crazy social media apps) :
https://www.tiktok.com/t/ZT2u6achp/
He uses a few different TL/big vented reflex shapes with the same basic architecture to ‘float’ a pillow case in the window and get to 148dB or so with two ‘small’ drivers (with huge X mech).
It’s all noise, not useful for music . Like a science experiment. Just for fun.
I guess there’s more here(if you can tolerate these crazy social media apps) :
https://www.tiktok.com/t/ZT2u6achp/
It is very impressive to see such small drivers and power recreate the experience of much larger systems. Im a skeptic but if its real then its real impressive and completely unique.
All of these can get incredibly ‘loud’…?
The trick is to pick one that works better for the particular drivers motor force or lack there of or it 💩s the bed @ Fb if you get overzealous/greedy 🤓
They all sound funky from the group delay /decay issues, etc surrounding the second resonace . But if it’s just to make ‘noise’ then it’s very interesting to explore ??
Tilting the baffle in the bottom one seems to help as well
The trick is to pick one that works better for the particular drivers motor force or lack there of or it 💩s the bed @ Fb if you get overzealous/greedy 🤓
They all sound funky from the group delay /decay issues, etc surrounding the second resonace . But if it’s just to make ‘noise’ then it’s very interesting to explore ??
Tilting the baffle in the bottom one seems to help as well
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