Normal
Re: More to a measurement then the transfer function?For speakers I use a laser displacement sensor now. I normally simulate the boxes and never have had a real issue although I have a pile of PCB Piezo stud mount ICP accelerometers I got when we worked on that quad-21in box. You can just check their website, they are for the most part pretty cheap, but you do need an ICP(IEPE) power supply. You can check eBay for the Endevco 2775A, which can normally be had for next to nothing ($20-50). It is a dual mode charge amp/ICP supply and will work for most any sensor you get your hands on. Charge coupled acceleromters are cheap on ebay but be aware they require special low capacitance wire normally with 10-32 connectors and need to be taped down so it doesn't move.
Re: More to a measurement then the transfer function?
For speakers I use a laser displacement sensor now. I normally simulate the boxes and never have had a real issue although I have a pile of PCB Piezo stud mount ICP accelerometers I got when we worked on that quad-21in box. You can just check their website, they are for the most part pretty cheap, but you do need an ICP(IEPE) power supply. You can check eBay for the Endevco 2775A, which can normally be had for next to nothing ($20-50). It is a dual mode charge amp/ICP supply and will work for most any sensor you get your hands on. Charge coupled acceleromters are cheap on ebay but be aware they require special low capacitance wire normally with 10-32 connectors and need to be taped down so it doesn't move.
