Hi members
i here have a microsub woofer 4inch diameter with a huge magnet and around 1.5inch voice coil diameter ... the surround is rubber roll and it is a long throw high excursion woofer but it is easy to push the cone down ... tried in a ported box currently around 9 liters tuned to 40Hz bass was quite ok but at the risk of reaching the xmax easily looking at the driver moves so easily
So now i was about to try something else ... i tried in a sealed box of about 2 liters it sound ok too ... now i would like to combine these two chambers together derive it into a 4th order bandpass enclosure (sealed size cone surface ported side = magnet) making the sealed chamber smaller so it could control the cone excursion then add abit shelving / Peaking EQ to boost the bass ... will this approach work?
just a side note when tested free air the cone moves quite alot but bass not really can be heard ... unlike large woofers ...
thanks
i here have a microsub woofer 4inch diameter with a huge magnet and around 1.5inch voice coil diameter ... the surround is rubber roll and it is a long throw high excursion woofer but it is easy to push the cone down ... tried in a ported box currently around 9 liters tuned to 40Hz bass was quite ok but at the risk of reaching the xmax easily looking at the driver moves so easily
So now i was about to try something else ... i tried in a sealed box of about 2 liters it sound ok too ... now i would like to combine these two chambers together derive it into a 4th order bandpass enclosure (sealed size cone surface ported side = magnet) making the sealed chamber smaller so it could control the cone excursion then add abit shelving / Peaking EQ to boost the bass ... will this approach work?
just a side note when tested free air the cone moves quite alot but bass not really can be heard ... unlike large woofers ...
thanks
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Without T/S specs; BP4 rule-of-thumb [ROT] is make the filter chamber 1/4 rear chamber tuned to 1.56*Fs.
Ok this driver unit just came to me past few days ago only have the time just to try to mess Around and experiment with them before taking the TS parameters ... If I am about to measure the parameters what type of characteristics I would expect from this driver ? My guess low FS and high QMS and QTS might be ��
Ok another thing still confused about the 1.56 *FS ratio what does it means? Still new to bandpass enclosure and don't want to mess up
Ok another thing still confused about the 1.56 *FS ratio what does it means? Still new to bandpass enclosure and don't want to mess up
No experience with these types of drivers, but WRT the other, just what it says, find Fs and multiply it by 1.56 as a starting point for your ~.222 ratio cab.
ah now my major concern is the excursion issue ... a TDA8950 class D in bridge mode (300W) driving this driver (rated rms 50W) tends to send ultra low bass to the driver which proves danger to the driver currently now is in a ported box ... so my major concern is how much excursion control the 4th order bandpass can put on the driver without destroying or damaging the driver? thanks
Using an oversized amplifier (and making use of the extra power) will always put the driver in mechanical trouble.
BP4 enclosures contain (to some extent) the excursion below the port tuning frequency, because the sealed chamber provides a strong restoring force to the cone. However, there's often a narrow band just below the port tuning where excursion can get quite large.
Mini-subwoofers can be fun to play around with, but I hope you're keeping reasonable expectations - it's a small cone, after all.
Chris
BP4 enclosures contain (to some extent) the excursion below the port tuning frequency, because the sealed chamber provides a strong restoring force to the cone. However, there's often a narrow band just below the port tuning where excursion can get quite large.
Mini-subwoofers can be fun to play around with, but I hope you're keeping reasonable expectations - it's a small cone, after all.
Chris
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about the amplifier obviously this wasnt the correct amplifier for this woofer due to the module i've assigned for it (TPA3116D2) purchased online but havent receive it yet (overseas from china) ... The TDA8950H was used for my 12inch DIY ported subwoofer (actual currently using unit)
and about the cone area i knew it was small too but looking at its super long throw ability i was curious to see how much this could put out but the cone is easy to push inwards without much effort (perhaps high QMS or OTS)... recently looking and reading about popularity of micro sub concepts ... and also came across some myth about excursion can replace cone area articles
i have two of them actually ... soon i will get the parameters and see what they indicates
and about the cone area i knew it was small too but looking at its super long throw ability i was curious to see how much this could put out but the cone is easy to push inwards without much effort (perhaps high QMS or OTS)... recently looking and reading about popularity of micro sub concepts ... and also came across some myth about excursion can replace cone area articles
i have two of them actually ... soon i will get the parameters and see what they indicates
You're welcome!
If truly sealed [usually some minor leakage around the driver gasket at increasing pressure], then any sustained or super high power [current] transient will heat up the VC at a ~exponential rate = the driver 'let's its smoke out' PDQ, often faster than you can 'kill' the power. 🙁
GM's comment is why I typically aim to put the driver's motor in the vented chamber if the driver is to see any real power.
Having the T/S parameters will help you get the most from this driver - you might find a smaller box tuned a little higher gets a more useful response. Of course, room acoustics etc will be at play.
Chris
Having the T/S parameters will help you get the most from this driver - you might find a smaller box tuned a little higher gets a more useful response. Of course, room acoustics etc will be at play.
Chris
Currently it was converted to bandpass ... Around 2 L for sealed and 7 Liter ported magnet facing ported side
There is a peak around 70hz but so far it sounded really nice ... This is a test box real box yet to be done ... Will include a transparent removable arcyclic panel for access the driver and able to monitor the excursion through the transparent window
There is a peak around 70hz but so far it sounded really nice ... This is a test box real box yet to be done ... Will include a transparent removable arcyclic panel for access the driver and able to monitor the excursion through the transparent window
