Originally Posted by gperkins1973
Your happy to slag off driver like FI, Mach Audio etc.. because it isn't a LMS and yet the PI18 is less than half the price off a LMS. And the Q18 is a 1/3 off the price of a LMS.
I don't think anyone would not be more than 100% happy with a couple off PI18's in their living rooms or even Q18's for that matter.
I don't think when you compare diy subs like FI, dayton and mach audio etc... each and everyone wipes the floor with any commercial subs out there.
I generally agree and wonder at the laziness of folks engaged in these discussions.
The Pi specs tell us claimed X-max and Sd which is all you need to calc displacement.
8 liters. You can then calc output at 10 Hz at X-max = 97.08dB.
The Fi Q specs tell us claimed X-max and Sd.
6.69 liters. 95.65dB. A difference of 1.43dB.
The Q-18 claims 92dB, 1W/1M. The Pi-18 claims 92.9dB 2.83v/1M, but it's a 4 ohm driver, so they're cheating 3dB. It would actually be:
Fi Q-18: 92dB 1W/1M, 6.69L @ X-max, 95.65dB @ 10 Hz @ X-max.
Pi-18: 89.9dB 1W/1M, 8.00L @ X-max, 97.08dB @ 10 Hz @ X-max.
The difference I see is in the drivers compliance, the Pi being the higher compliance driver. After messing with dozens and dozens of drivers, I tend to lean toward the sonic sig of a stiffer suspension driver, but the difference is slight enough that I agree... not many could pick a difference given same alignment, same upstream hardware and same calibration/playback levels.