Ok so this is technically car audio but I'm looking for any other options for bass in approximately 8l of space(0.3cuft).
Firstly yes I know it's tiny and not to expect a lot. Power is around 2 to 300 wrms which should be more than anything in a box that size can use.
Aiming for 40-80hz in car. Just a little fatness in the bottom end, not window rattling.
My constraints are using an existing enclosure with room for what appears to be a single 6.5 inch driver. I AM ABSOLUTELY open to modding the enclosure with bigger cutouts etc or even glassing in a baffle of some sort.
Enclosure is mounted under a seat and is an odd shape. There is room for a passive radiator by the looks, but at most an 8". Woofer depth is limited to about 125mm (5") and above baffle maybe 3/4 inch including surround excursion.
Really keen to see what driver choices are tucked away. I probably could just find a small enclosure 8 and shoehorn it in (Even an Alpine R 8 says as small as 0.15cuft sealed). Also eyeballing the tangband drivers too. Kenwood shallow 8? Even a pair of 5" subwoofers mounted on the front with the existing hole glasses shut? Pic attached of front side of enclosure, OEM woofer is behind grille on too side. Top is approximately 21.5cm square. Bottom is bigger/longer and front is 22cmx14cm
Open to suggestions for crazy small box drivers🙂
Firstly yes I know it's tiny and not to expect a lot. Power is around 2 to 300 wrms which should be more than anything in a box that size can use.
Aiming for 40-80hz in car. Just a little fatness in the bottom end, not window rattling.
My constraints are using an existing enclosure with room for what appears to be a single 6.5 inch driver. I AM ABSOLUTELY open to modding the enclosure with bigger cutouts etc or even glassing in a baffle of some sort.
Enclosure is mounted under a seat and is an odd shape. There is room for a passive radiator by the looks, but at most an 8". Woofer depth is limited to about 125mm (5") and above baffle maybe 3/4 inch including surround excursion.
Really keen to see what driver choices are tucked away. I probably could just find a small enclosure 8 and shoehorn it in (Even an Alpine R 8 says as small as 0.15cuft sealed). Also eyeballing the tangband drivers too. Kenwood shallow 8? Even a pair of 5" subwoofers mounted on the front with the existing hole glasses shut? Pic attached of front side of enclosure, OEM woofer is behind grille on too side. Top is approximately 21.5cm square. Bottom is bigger/longer and front is 22cmx14cm
Open to suggestions for crazy small box drivers🙂
Attachments
Wel recently i installed a Tang Band W6-2253S in a 8L sealed cabinet for the cabin of his small truck of a friend. He uses it with an amp with dsp altough but hits 30Hz with it (with dsp eq). 2 of those cabinets are hidden behind the seats of the driver and the passenger in his truck. Tops are Focal coax car drivers that replace the shitty speakers in the doors of this (Renault Master) truck that he uses for his gardening bussiness. Amps are a 4 ch Audio Control device with dsp. That guy listens to oldskool dubstep, steppers dub and dnb and has now all the bass he could wish for in his truck...
You will never be able to calculate this. Under a car seat the importance of the cabinet is reduced as factor. Consider this: listen to a driver in free air. Place the same driver under your car seat and note how it sounds different. Whatever factors affect the sound of that driver will still have some effect even when installed in a cabinet. Every surface affects wavelengths, the waves are reflected but also reflected by angle. Every little gap between cabinet and fitting can produce a port effect. Foam in the seats contribute to damping factors . . . and if you move the seat forward . . . every parameter changes.
Listen to a speaker in a car door. Despite being the same driver in the same enclosure, the sound differs depending on whether the door is open or closed.
Car systems are extremely volatile. Just imagine how your life could have been better. You could have given Becky-Sue a lift home after prom. Maybe you would have hooked up. One of your four kids may have become leader of the free world but you said no because you'd just bought the new NWA CD, and there's less bass when somebody is sitting in the passenger seat.
My bad.
Listen to a speaker in a car door. Despite being the same driver in the same enclosure, the sound differs depending on whether the door is open or closed.
Car systems are extremely volatile. Just imagine how your life could have been better. You could have given Becky-Sue a lift home after prom. Maybe you would have hooked up. One of your four kids may have become leader of the free world but you said no because you'd just bought the new NWA CD, and there's less bass when somebody is sitting in the passenger seat.
My bad.
I don't need to calculate the vehicle. The sub box is fixed inside the seat. It won't change. Also it's a subwoofer, wavelengths are long enough that trying to calculate seat foam is a massive waste of pedantic time.
All cars have odd acoustics but with wavelengths longer than the cabin, it becomes more about cabin gain than a seat position change.
I would like to know which drivers people would recommend for such a small volume. Not a FEA measurement of cone deflection in proximity to a seat cushion.
All cars have odd acoustics but with wavelengths longer than the cabin, it becomes more about cabin gain than a seat position change.
I would like to know which drivers people would recommend for such a small volume. Not a FEA measurement of cone deflection in proximity to a seat cushion.
Most shallow woofers have a mediocre xmax. If a deeper woofer fits, that usually is cheaper and better.
It is real, it's the maximum excursion of the cone that is linear. Off course it can go further, but that won't be linear and often sound bad, and when going over the xlim distance, it damage the driver. Limited xmax and xlim means limited volume in bass, wich can be augmented by the alignment (horns and so). But more xmax means louder and deeper bass in most cases. So it's certainly a factor to take in account. And to play save, take xmax as guidline (certainly for hifi). And in this case, in a very limited space, horns or other ways to move a lot of air with limited xmax won't work.
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Do you know speakerboxlite?
SpeakerBoxLite. Subwoofer box calculator, Sub box calculator
It´s an online tool for a quick loudspeaker sim but most importantly it has a pretty big database with drivers.
Instead of choosing ("choose") the driver directly, click "choice" under "speaker",
then say closed/vented and give the volume.
Afterwards you can filter for certain diameters and sort the results by f3.
By conincidence it brought up a driver I once used in a sealed linkwitz-transformed "fast",
the Reckhorn D-165 but that needs vented to get as low as you wish.
SpeakerBoxLite. Subwoofer box calculator, Sub box calculator
It´s an online tool for a quick loudspeaker sim but most importantly it has a pretty big database with drivers.
Instead of choosing ("choose") the driver directly, click "choice" under "speaker",
then say closed/vented and give the volume.
Afterwards you can filter for certain diameters and sort the results by f3.
By conincidence it brought up a driver I once used in a sealed linkwitz-transformed "fast",
the Reckhorn D-165 but that needs vented to get as low as you wish.
Xmax is not a real (relevant) thing. Consider the internal combustion engine: cylinders are measured in bore and stroke. When exceeding the perfect ratio, increasing stroke length to improve power output becomes both inefficient and problematic.
Rubbish example for a false statement.
Bore and stroke in an internal combustion engine are chosen for what you want the engine to be good at. As an extreme example a current F1 motor has a bore of 80mm with a stroke of 53mm displacing 1.6L in it's V6 configuration producing 1000hp at 10500rpm. It is not all that efficient but good at high rpm and high power.
On the other hand the most efficient internal combustion engine has a bore of 960mm and a stroke of 2500mm producing 7670hp per cylinder at 102rpm. It has between 6 and 14 cylinders.
Bore and stroke in an internal combustion engine are chosen for what you want the engine to be good at. As an extreme example a current F1 motor has a bore of 80mm with a stroke of 53mm displacing 1.6L in it's V6 configuration producing 1000hp at 10500rpm. It is not all that efficient but good at high rpm and high power.
On the other hand the most efficient internal combustion engine has a bore of 960mm and a stroke of 2500mm producing 7670hp per cylinder at 102rpm. It has between 6 and 14 cylinders.
I don't think you can draw that analogy that direct (altough it's true big driver cones need less xmax to get the same volume, but it's not a linear thing like with combustion engines). But the other is still also valid, xmax (in combo with the cone size) dictates how much bass can be generated for that cone, and too little is not good. So stating xmax does not exist is wrong, it does. And in this case it's a small box with a small driver, so xmax is surely important to get the bass needed.
Could you stretch for enough physical space to fit a baffle for a 10", most 10" pancake subs only need about that volume if going sealed
Yes, it´s quite a nice online tool that you can even use at work should one have a boost of creativity ;-)
I believe the Loudspeaker Database has a bigger range of drivers.
But there you´d have to know what you´re looking for (filter for Qts,Vas or similar).
Like this:
Loudspeaker Database
The Tangband W6-2100 doesn´t look too shabby in 8l sealed for such a small driver.
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😡
Negative, the top or bottom of the enclosure is 22cm roughly across. Either side of that are steel seat rails etc.
I'm starting to consider a possible 8 inch driver in that box and an easily removable second 8 or even larger in a similar sealed enclosure in the back. I'll be overlaying phase responses etc to make sure they both function together.
We're still talking about a people mover, not an analytical HIFI environment haha. Wife just wants some bottom end for her favourite tunes.
Negative, the top or bottom of the enclosure is 22cm roughly across. Either side of that are steel seat rails etc.
I'm starting to consider a possible 8 inch driver in that box and an easily removable second 8 or even larger in a similar sealed enclosure in the back. I'll be overlaying phase responses etc to make sure they both function together.
We're still talking about a people mover, not an analytical HIFI environment haha. Wife just wants some bottom end for her favourite tunes.
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There are so many false representations and equivalences in your statement that it makes no sense. In efficiency of displacement a single cylinder of your diesel engine is over 1000 times the total volume of an F1 engine, yet can only manage less than 80 times the power output.
Perhaps the most relevant data in your post the lowly 102 rpm - it takes time to move the piston over the long stroke distance. In terms of xmax: the the further the diaphragm has to travel, the greater the amount of time it takes. In very simple terms: after travelling to its full excursion to produce one note it needs to return to its 'starting position' to produce its next. There is also the increase in Doppler effect to consider.
That diesel engine is the most thermally efficient engine ever built, it turns more of the energy contained in the fuel into motive power than any other internal combustion engine.
Compared to it an F1 engine is thermally inefficient but it is more a efficient use of space.
Compared to it an F1 engine is thermally inefficient but it is more a efficient use of space.
Sikver Flute W14 in an 8 litre miniOnken is good to near 40 Hz F10 anechoic so should be flat below that given the cabin gain in a car.
The driver is 75mm deep so should easily fit.
dave
The driver is 75mm deep so should easily fit.
dave