Re: For any one who has experience with the JBL MS8....
This is addressed in the giant MS-8 thread on DIYMA, but I can try to answer it to make it easier.
When you calibrate the MS-8 there are sweeps that play through the speakers. These need to be at around the same level as if you had someone in your passenger seat talking. You do this by adjusting the gains on your amplifiers if you have all speakers and your sub powered separately. The subwoofer gain may need to be turned down quite a bit. Andy Wehmeyer always says the bass sweep should be heard but not felt.
During calibration you need to set the volume on the MS-8. This is discussed in the manual. I've had best results setting it at -30, then after it's set up I set it to -10 and use the volume knob on my head unit. For anyone curious reading this thread, this is what worked for me on an all aftermarket system. Do not follow these instructions if your system is different. Read the manual.
If the levels were good during calibration you should have great imaging right away, although it will probably sound thin and lifeless. Don't forget to unplug the mic. If your imaging is good go into the graphic EQ and draw the curve to shape the sound how you want to hear it. I do +9 dB up to 60 Hz, gradually slope it down to 0 before 200 Hz, then it's flat until 10 kHz or so at which point I start to roll it off. This is when you start bringing the gains up on your amps. They all need to come up the same amount to maintain the equalization curve, and the "2V" position is your goal. It doesn't have to be there but this part was left out of the manual and it's what Andy recommends.
Don't turn up the sub amp's gain past 2V. It doesn't have to be precisely at 2V and you can't use a DMM to set it with MS-8. If the bass still isn't loud enough use the sub level in the MS-8 to bring it up.
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