I have a no brand 15”, no specs data sheets or anything. It looks rugged PA and I plan to make a subwoofer of it in a 140l cabinet. I’m just not sure whether to make it sealed or with port. But I may not have a choice given the magnet pole vent? I assume that in a sealed enclosure the pole vent would actually pump air into the dust cap making all sorts of unwanted noise and maybe even hurt the cone by opposite forced between the coil movement and the air going through the pole and into the dust cap? I have no idea about this though and wonder if anyone know more about the subject. Also I would like to try to measure TS parameters before doing anything, any guidelines how to do so? Which parameters are crucial for a sub enclosure sealed vs ported and how to measure those as simple as possible.
This is the driver:
Fence Audio 10959511 15" bass til STAGE-1515.3 - Komplett.no
This is the driver:
Fence Audio 10959511 15" bass til STAGE-1515.3 - Komplett.no
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the pole vent is to realease any air pressure build up under the cone dust cap. this is good for all enclosure types. if you driver is suitible for a vented box can only be answered if you measure the ts-parameters, download arta or rew or both
But wouldn’t the cone area outside the dust cap on the backside create even higher opposing force back into the vent if the enclosure is sealed making the dust cap pressure even higher that if there were no vent? Like this would actually be the speakers tiny bass reflex creating a high speed compressed air straight into the dust cap possible stressing the glue and eventually break the dust cap free from the cone? The moving mass outside the dust cap is a lot bigger. It must be a requirement with ported enclosure from what I can understand. Anyway will try those tools I’m sure a vented box would be preferred for this driver in any case but would be great to try to find Fs qts vas at least not to mention impedance.
If you want to see a high-end design with a ventilated woofer in a sealed enclosure see here: Zaph|Audio - SB12.3 3-Way Tower
If you look at the T/S parameters for that woofer, you'll see that it is meant to be used in a sealed cab (Qts > 0.4). You need to measure the T/S parameters of your woofer to understand what type of enclosure it needs, and of which volume.
Ralf
If you look at the T/S parameters for that woofer, you'll see that it is meant to be used in a sealed cab (Qts > 0.4). You need to measure the T/S parameters of your woofer to understand what type of enclosure it needs, and of which volume.
Ralf
no i guess not, if this would be a problem then no mfr would make these. but this could be a problem if the dust cap did not move with the cone and where out of a flimsy material. but air pressure be a problem with drivers with phase plugs or with coaxial drivers, there is a gap between the phase plug or the tweeter and the voice coil former, this gap can let air in/out of the box and this airflow can make noise. the venting in the motor can also be designed with airflow in mind, this airflow can cool voice coil heat at high drive levels
Thanks seems I over worry about this then, it’s probably not an issue. I’ll get back to read up how to measure TS.