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Help with a PBR300X2 set up

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Completely new noob with audio here so bare with me. Been reading all over the internet and here about setting up my system. Breif run down of my set up, this is on a 2010 Harley Davidson Street Glide with the stock Advanced Audio Harman Kardon head unit. The only specs I can find on the head unit is 20 watts RMS per channel at 2ohms. I just installed a set of Polk Audio MM651 in the fairing and should have my RF PBR300X2 some time this week and hope to install it next weekend. I kind of understand the procedures for setting the gain on the amp and how to find the max output from the head unit with a O scope but all I have is a DMM.

Now for the million dollar questions;

To find the max volume of my head unit with out distortion, I taks the RMS wattage = 20 and multiply that by the ohms = 2 and the I find the square root of the total = 40, sqrt = 6.32. So do I disconnect the speaker? and turn to volume all the way down, connect my leads from my DDM to the speaker output from the head unit and start turning the volume up till my DMM reads 6.32 v AC and note where the volume level is and thats my max volume with out distortion?

If the above is true, then setting the gain on the amp will follow the same? RMS wattage = 150 X ohms = 2 = 300, sqrt = 17.32. So connect head unit to amp and my leads from the DMM to speaker output from the amp and adjust the gain till my DMM reads 17.32 v AC?

Man I hope Im right so far.

So now is where I really get lost.

What frequency tone should I be using to tune with? 60hz, 80hz? Seeing as the speakers are 6.5" coaxial, I don't see pushing alot of bass. I assume this will be mostly mids and highs. I listen to mostly rock and country so was thinking of making my tone -3db or -5db use Audacity tone generator.

Now then next question; I will be running the amp in HP and the frequency is adjustable from 50 to 500 hz, where should I start? I undersatand you adjust this to your liking but I have no idea as to where to start.

Last question; what is the HL Adjust for? It adjust from 4v to 6v. If I understand this right, it kind of works like a remote on/off switch and will pick up the power on from the head unit thru the speaker output and powers on the amp? If so where should I set that at and if not what is it for and where should I set this at?

Sorry for the long post and noob questions. Thanks for the help.




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Well the HL adjust is basically a remote that is adjustable it is mainly to keep from having pop noise when the amp comes on and off. I never adjusted mine and seem to get a pop now and then but aside from that I see no need to mess with it from factory unless your amp is not coming on (assuming the switch for it is on). The rest I will let someone more experienced chime in.

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