What amp to buy?

I bought 4 6.5" Krypt HLCD tower speakers and I am looking for a amp to power them and only them. I was looking at an Alpine PDX F6 however someone told me that they had experience with it and also a Arc Audio KS 300.2 and the second was better. Does anybody know which of the two would perform better or have another suggestion?

I would suggest the alpine pdx150x4. I use it to run 4 pro 80's and it is great. uses little power and stays cool. Also a very small platform.

I just looked up the Alpine and I guess that is the new version of the 150X4. Mine has been in for 3 years and no issuses.

Either is an excellent choice, I'd personally give the edge to the Alpine.

The difference in the amps is this:
150x4 @ 4ohms with the Alpine (conservitive rating)
350x2 @ 2ohms (175 watts per speaker) with the KS 300.2

4ohms is cleaner (negligable in an open air environment) and more effecient as is the class D topography of the Alpine. The Arc is G/H also very effecient but a little less. Again they are both very nice amplifiers and I doubt you would be disappointed with either of them. With that said it'd probably come down to price for me.

That ARC amp is like 65% efficient, the Alpine more like 80% if that makes a difference to you.

The Alpine is nice but I think the ARC has a little more balls. You can also use the ARC 300.4 but I would prefer the 300.2. Or... 2 300.4's bridged pushing 350 to each OVERKILL for sure. You can also use the wetsounds Syn 2 and get a true marine amp with a nice stainless steel mirror finish. I am running wetsounds amps in my boat and could not be happier.

Here is some more info on the Arc Amp. http://www.arcaudio.com/productpics/...3002review.pdf

At 2 ohms the arc amp is 67% percent efficient....I would like to see some info stating that the Alpine is 80% efficient. Also conservative rating - where did you hear that? Show me a test report!!!!

Yes, the Arc has more balls....I have heard and seen the "balls" on both amps. The Alpine is not a bad choice if that is what you end up with.

I do agree that the class D are more efficient than g/h - but I did not know they were that highly efficient if that is correct. Also - on the alpine does the efficiency decrease when you go from 4ohm to 2 ohm.

On the conservative rateing - could be...I don't know. My logical thinking tells me that the amp manufacturer would want to publish the highest wattage per channel possible in an effort the sell the amp in the best light possible. I think the rateing system got so out of hand at one point (on the high end) that they came out with standards to rate amps moving foward.

Either amp will get the job done. I personally prefer the Arc Audio amps b/c I have put them thru the wringer and they have never failed. I would also look at the JL Audio HD - great amo

My buddy has 5 Alpine PDX amps in his Epic and they rock! The one thing about the Alpines, they deliver the same power at 2 or 4 ohms so the 4.150 delivers 150 watts rms at 4 ohms or 2 ohms whereas other amps usually deliver more power at 2 ohms so not sure if that matters to you long term as far as adding more speakers to the same amp.

The Alpine Class D is a bit more efficient. Its four-channel and puts out its full rated power into 4-ohms so there will be no change in efficiency, damping, distortion, etc as applied in this case. Other topologies will marginally lose efficiency, lose damping and increase distortion at a lower 2-ohm impedance. The Alpine amplifiers ship with a birth certificate that routinely demonstrate that they deliver a bit more power over their rating. The Arc test report shows that it exceeds its rating too. Neither of these amplifiers will be delivering the same power from the typical voltage supply available in a boat. It will be less. If we are going to hear a difference in power it is going to have to exceed a 33 percent increase to constitute a 1 dB difference. We are talking here about a smallish 6.5-inch HLCD that is dominated by the horn with little midbass and balance so I doubt we'll hear a difference in tonal qualities between these two amplifiers. It could be different with another tower speaker. The minor efficiency difference may not show up in the context of an entire system depending on all the other components and potential issues that also affect efficiency.
If I could find one tiny difference it would be that if you seriously abuse both amplifiers I might put my money on the thermal capacity of the Arc Audio amplifier. The Alpine might self-protect sooner. Or, you can flip a coin.

David
Earmark Marine

So then it comes down to price?

Murphy, I was referencing the birth sheets that come with the PDX as David describes. One can routinely find them in the 8-12% range higher than is rated.

Just as I said above it'd come down to price for me.

yeah I am starting to see that the alpine is not a bad little unit. the op will not go wrong with either choice.

considering the Arc msrp is $399 and the Alpine msrp is $749, I think I will go with the ARC. Thanks for your help.

If you pay MSRP for either one you are getting hosed. I bought my alpine brand new for well under 400