I have a 2012 Road King with a Boom Audio system mounted in the windshield. I hate that I lose sound when I remove the windshield so I'm working on a system to replace it.

I've got a sret of lower fairings coming and will put 6.5" speakers in the pods. Right now, just because of price, I'm going to try the Polk DB651s speakers. They were third place on a poll I read here so I figured I'd roll with it. Plus, the amp I'm going with is the Rockford PBR300x4. The speakers are 4 ohm and so it should work well with that amp. I found a cool cord that goes from the 30-pin iPod/iPhone/iCrap device to dual RCA out and a power line with in line volume control. I'm hoping that will work for at least a short while.

What I'm having issues with right now are a couple of things:
Where should I mount the amp? I hear it gets hot, maybe enough so to melt plastic. I'm wanting to put it in the amp but just not sure exactly how. Anyone got pics of theres?

Also, I'd like an AM/FM radio with satellite and a way to connect my iCrap to that. Any solutions there?

Just curious what people's thoughts are and what they'd do differently.

 

1.) PBR300x4 is a terrible amp. It overheats, sound quality is terrible, just a bad amp. However there has been NO proof whatsoever that it gets hot enough to melt plastic, only hear-say. My question though is why would you still want to install it knowing all this?

2.) DB651 speakers are not an ideal choice either for their lack of power handling capabilities when using any sort of decent amp to drive them.

If you're going with a 2 speaker setup then I would take a look at the Polk Audio MM651, Biketronics Titan II, or Focal speakers for your lowers. I would compliment those with the PBR300x2 amp. The amp is small in physical size so throwing it in the bottom of a saddlebag is certainly an option. Heck, it's so small that you might even be able to get away with putting it under the seat or a side panel but exposing it to the elements might not be such a great idea either. The Polk MM651 would IMO be a better choice as they more closely match the amp so as to utilize the most output power possible.

 

Well, as you mentioned, all of the info I have heard on the 300x4 is just hearsay hence my post asking for opinions (which I appreciate!). The part about getting hot enough to melt ABS plastic...well, that was just one person's comment on one post....strange but I figured I'd ask about it. I wasn't aware that the amp was a bad amp. I've talked to a couple of guys that are using it to push their set of Hertz speakers and love it. Interesting that the amp is crap as a 4-channel amp but good as a 2-channel amp. Either way, I do want a 4 channel amp so I can upgrade later (if I decide to) with speakers for the saddle bags.

I'll look into the MM651s. At first glance, they're 2.7 ohm speakers and I recall a post recently talking about issues with not running a 4 ohm speaker. I'll have to call a couple of local shops and ask about the truth to that rumor (specifically, that amp should have 4 ohm speakers with it to avoid damage to the system). I'm not a stereo guy...stock has always been enough for me.

Good stuff though. Any other input?

 

The object of this audio game is

Match the amp to the head unit. This is done via the outputs of the head unit and the input gains on the amp. Then you match speakers to your amp choice.

If you buy an amp that is stable down to 4 ohms, then buy 4 ohm speakers. If you buy an amp that is stable down to 2 ohms, then buy speakers that are 2 ohm. By using a 4 ohm speaker on a 2 ohm stable amp, you're effectively losing about 1/3 of the amps output power.


Matching is the key to a good sounding system, not just putting stuff together in a slap-happy manner and hoping for the best.

 

Interesting part is you either get a good one, or you get a bad one. The technology is the same, boosted rail so makes no sense to me either and when questioned about it, RF R&D can't give a straight answer either.

 

So, if I don't have a head unit, what's a good starting point? My iPod or whatever device is going to be the main audio source. Speakers, got it, the MM651s win over the DBs...seems the main difference is that the MMs, while a few dollars more, are a monitor style speaker so that would help in this application I'm assuming.

Aside from that then, what's a good 4-channel amp to run (since I want the option to upgrade later)?

 

The main differences in the speakers are the impedance (2.7 ohm vs 4 ohm), power handling capability, and sound quality.

there are a few good options out there for 4 channel, 2 ohm stable amps

Alpine PDX-F6
JL Audio XD400/4
Soundstream PN4.520D (my preference)
J&M/ARC 4 channel amp

Just depends on how big physically you can live with and what you want to spend on it. As for the input device, you'll need something like a 3.5MM to RCA Y adapter to allow for 4 inputs to the amp.

 

Awesome...I'm looking into the Soundstream. Thanks for all of the information!