Maybe this is about a crossover. You can guess at some component values if you know the impedance of the driver at the crossover frequency. Does this sound like it?
Not syntax usually used. Ask what he means. He may m4ean the TS parameters for the woofer, he may mean what derivers yo are loading into it. What "analysis" are you talking about? Acoustic? Resonance modes? WAF?
Have you downloaded any of the usual box design CAD programs? I use WinISD and Edge mostly, but there are many choices.
Have you read the various threads on materials? Personally, with the exception of subwoofers, I have never found anything I can't do with 3/4 MDF. I have used 5mm Birch ply for smaller ones.
Have you downloaded any of the usual box design CAD programs? I use WinISD and Edge mostly, but there are many choices.
Have you read the various threads on materials? Personally, with the exception of subwoofers, I have never found anything I can't do with 3/4 MDF. I have used 5mm Birch ply for smaller ones.
Could be the box load on the driver, ie volume and tuning (if vented), or the box vibrational load.
dave
dave
If the estimated load analysis is for rigging purposes, T/S parameters and impedance loads make no difference to the calculations, but enclosure thickness, material and construction all do.
In the world of structural engineering, "estimated loads" are the external loads applied to a structure. For example, a pedestrian foot bridge might have a load requirement of 200 lb per linear foot of live load (people, bicycles, etc). An aircraft wing might be 25 lb per square foot of air load. A cell tower might be designed for 2x10^6 ft-lb of bending moment. So I suspect the OP has been talking to a structural, civil, or mechanical engineer, since this is how they would ask for requirements.
This engineer may not understand the nature of the problem. Loudspeaker enclosures are not normally designed to withstand a particular load. Instead they are designed with a particular combination of stiffness, mass, and damping such that they have structural resonances which are the least intrusive and annoying. What that particular combination is, well, that is something we do not all agree on. However, a good basis to start your conversation with this engineer is to say that there is no strength requirement for the cabinet, but it must be as stiff as practically achievable.
Here is an answer to your last question, from Linkwitz: https://www.linkwitzlab.com/images/graphics/enclosure-spl.gif
Other than that, he is likely looking to design your box for either closed (acoustic suspension) or open (vented or bass reflex) operation--which you specify. The calculations above provide worse case environmental conditions inside the box for closed box operation.
This is probably the best answer, since you have not apparently given your analysis person a constraint on the box design.
- Size/shape is probably well known from the various programs/simulations that will estimate low bass response given a particular acoustic driver parameters.
- Freedom from resonances is probably what you need to talk to him/her about. Discussing how to reduce resonances inside the box with a driver in it is probably your real task. This includes internal stiffeners, if any.
- Handling loads and in-service accidents usually help to determine whether or not you're using MDF or plywood, etc., as MDF has a significantly lower survivability capability than plywood.
- Maximum weight is also a constraint on design, as well as cost of the materials and the required assembly time.
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