Is choosing a Woofer the same as choosing fruit at the market?

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This woofer has a high Qts of 1.47

Have you checked that figure out against the 'Q Parameters' section in my Eminence link?
 

stv

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This woofer has only 2.5 mm Xmax. This limits the output at low frequencies - such as 6 W maximum at 30 Hz.
Keep in mind that the Xmax may just be limited by distorsion, so the driver can probably survive more power, but it will sound distorted.
 
If your $ budget for the woofer is in that range have a look at this driver from Dayton Audio. https://www.parts-express.com/Dayton-Audio-DC200-8-8-Classic-Woofer-295-310 It has a lower Q and a bit larger Xmax. So the required box will be smaller (less costly) and the max SPL at the low end will be a little higher. You can go beyond the Xmax by maybe 50% without damage, but the distortion is high. Xmax is what really what you pay for. Commercial speakers often use vented designs as you can get about 6 dB or double the low bass from a woofer, at the added expense of a larger box and a very poor transient response. So you can spend your money on a woofer in a small sealed box or you can buy a less expensive woofer and spend the money on a large box for a vented design or a really large box for a transmission line design. You will see the cone area, and thus the displacement and maximum SPL at low frequency goes up rapidly with each increment in cone diameter. Thus a 10" woofer will have a much larger cone area than an 8". Again, deciding how loud you want the the driver to play the lowest frequency determines the displacement required and you can match the Xmax and cone area to that. This applies to every driver in a design, woofer, midrange and tweeter. If you look at my spreadsheet on the last page you will find I have woofers, midranges and tweeters listed there. As noted by another post, this applies to sealed boxes. A rough estimate is to add 6 dB for a properly designed vented box. I attached the file so those without a google account can use it. Unfortunately these websites don't have the option to sort woofers based on Xmax and they don't specify if the Xmax is peak to peak or zero to peak. So you have to go to the manufacturers website and check the spec for yourself. It's a sham ... shame.
 

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