Starting a new thread...sorry for highjacking another.

I could use some more advice on adjusting my PBR300x2 gain powering a set of Polk MM651s in the fairing. A lot of questions here to get better knowledge, and I hope you can help me out.

I've played around with several settings including HU volume, gain adjust, and crossover settings. I set my PBR amp gain by using the ear method (~5 on the amp) with HU volume set at between "m" and "e" on the HU (don't recall how many bars that was) with crossover set to AP. At that gain setting the amp BRT light flickers, and I had what I thought was plenty of margin to distortion. When I turned up the volume and made slight adjustments to treble (+1) /bass (+2) and fader (3 bars to front) to balance sound from the rear pod speakers. (I'm driving a pair of J&M 5.25 inch speakers in the pods from the stock CVO boom amp under the tourpak) the system sounded pretty good in the garage and while out on the road.

Now, here's my problem and where I hope a little tweaking can help out. It seems the longer I'm on the road the sound coming from the fairing MM651s (being driven by the PBR) seems to get more sloppy and it periodically distorts. When this happens it's a matter of time until the sound stops coming from all the speakers (front and rear), then I have to power off/on the HK head unit to restore sound. I'm wondering if another adjustment of PBR amp gain/crossover settings could help prevent this distortion.

And yet more questions...
(1) What could be causing this distortion, and then subsequent shutdown of audio? If it is likely a HU problem then I want to send it off to Iron Cross Audio to get it checked out. Alternatively, could it be an amp problem - either the RF PBR driving the fairing speakers; or the CVO boom amp driving the rear speakers?
(2) What is the function of the PBR's BRT light, and when setting gain should you adjust H/U volume (using ear and no distortion) so that the light is off, flickering, or steady? I had assumed when I set the gains in the garage that if the BRT light was mostly flickering I'd have margin to distortion when I increased volume on the road?
(3) Might a better approach when setting PBR gain is to reduce the HU volume setting (with a large margin to distortion), and then increasing the amp gain so that the BRT light is steady and I'm getting the desired loudness out of the speakers?
(4) Does the crossover setting (AP/HP/LP) on the PBR300x2 affect the onset of distortion? When I e-mailed RF support they recommended setting crossover to HP at 80 hz, but the Polk speakers sound better when set to AP as I seem to get more better bass and fuller sound. Do you think I should stick with the AP setting?

I've asked a lot of questions...Any other tips are much appreciated.

 

unplug the connector on the CVO amp and go ride with just the PBR amp and front speakers connected.
BR light is to indicate when the amp switches to high power output and increases the voltage across the mosfet output rails to suit the needs of it's currently driven stage.
negative. set your bass and treble to flat on your head unit. (middle)
turn your gain all the way down
put in a source music track that is dynamic in nature (for example Van Halen). DO NOT use rap music to set your gains..
turn your head unit up until you head distortion (usually about 13 bars but depends on the type of music) then back it down a notch or two.
turn gains up until you hear distortion then back it down a little
you will get a much fuller sound in AP mode because it is after all, ALL PASS meaning no frequencies are cut out or dropped.
the crossover and it's associated frequency settings are really speaker dependent. If you've got a speaker that can't handle bass, then turn it to HP, start out at 80hz, and go from there. What this does is cuts out any frequencies below 80hz (which is bass/mid bass) and allows everything else to flow through.

no other tips other than to realize these are 6.5" speaker being hammered by a 150/channel amp. You cannot realize the full potential of your audio investment until you get that CVO amp out of the equation and replace those rear speakers with something more suitable. This will create a more "corrected" sound stage for your listening enjoyment.