Originally Posted by WagBoss
how would i test that? I am thinking that it is most likely the headphone out on my laptop that can't output below 20 hz. I want that content though, that is the whole point i am building this subwoofer lol. Well sub 20hz from blu-rays not from my laptop, I was just testing the sub with it.
Do AVR's ever have any type of high pass filter on their LFE output? I know my minidsp is set to a 18 hz high pass filter but that still lets content through below, right? Maybe I have it too steep..
i doubt your laptop headphone out ain't capable of doing below 20Hz. i have a similar test rig as you:
minidsp plugged into a dell latitude e4300 through the 3.5mm headphone out and into a bridged class d amp.
it's fairly easy to test if your laptop are capable of outputting below 20Hz tone: use a software tone generator, ramp the volume level to max on the laptop and look at the minidsp input gain screen. if there's a tone playing from the laptop then minidsp will detect the tone and give a level. make sure to remove any high pass, low pass crossover that you might have.
and do this without turning on the amp powering the sub. you don't wanna give full sine sweep to a driver in free air.
or if you have any external usb powered speakers plug them in and generate a 20hz tone. my laptop speaker could produce a low tone when i generate 20hz tone without anything connected.