Originally Posted by bass addict
Originally Posted by beastaudio
Reference is when your system's speakers are all calibrated to 75dB's and the volume of the AVR is at -0. There is NO other reference. If you listen that loud, then that is where you want to start your AVR off with the sub trim level at 0.
That's not entirely true. Technically I could set reference up any given volume level I choose. Not all receivers are setup for reference at 0db because not all use the same display function. A friend of mines starts at zero and goes up from there.
The difference is "relative vs absolute" volume reading. Most modern AVRs with automated correction that I have setup have the Relative volume display which is relative to reference, with "expected" reference to occur at the "0" reading. However most home setups run out of gas waaay before reference in one way or another. I haven't seen an AVR without at least the option for relative volume display in yeaaaars.
another thing to strongly consider is your high pass. Without the highpass filter you will likely damage the driver and it won't sound good either with the woofer flopping around under tuning. The EP4000 is flat to 5hz minus a db or two. It doesn't roll off @20Hz like your stock plate amp. This was on purpose to protect the driver.
Another thing to consider is you have no way to control the power to the driver. That amp puts ~650W into 4ohms which is nearly twice the power the original amp was capable of. This might sound good MOAR POWER!!!!!, but in reality without a high pass and too much power you will likely kill that driver.
OPTION: You could always seal the box and not worry about the high pass. This will however decrease the output capability of the sub but should help keep the driver out of trouble. Notice I said help, b/c in ~3.0ft^3 sealed that woofer still cant take 650W and stay under x-max. I sealed a couple of mine this way and am currenlty using them sealed but with only 250W each.
Not trying to discourage you, but if you do this like your saying you better have better disipline with the volume control than I do!!!!!