Amp Options

My new boat is coming in next week, and I’ve been trying to plan out my stereo system. I’ve got everything picked out minus the amps. The shop that does all the dealer’s boats is recommending Arc Audio KS 300.4. From everything I’ve found, they are supposed to be great amps, but a little pricey.

Does anybody have any other suggestions which will have similar performance, in a more economical amp?

Arc KS 300.4 stats:

Power output RMS @ 4 ohms 4 x 90 watts
Power output RMS @ 2 ohms 4 x 175 watts
Power output RMS @ 4 ohms bridged 2 x 350 watts
Transient Distortion (100 watts) <.02% @ 4 ohms
Frequency Response 20Hz - 20 KHz
Signal to Noise Ratio >95dB
Bass Boost {+18db@45Hz,+18db@45Hz}
Crossover (Butterworth) 55Hz - 5.5 KHz variable 12dB

(Message edited by brian_young on March 27, 2008)

I went with the Cadence ZRS3002- Pair of Pro 485's and Cadence ZRS9004 for the inboards- 6 WS XS650's. What are you looking at using the amp to run? I picked up both of these amps for $500 shipped.

(Message edited by pfort on March 27, 2008)

Arc Audio has some awesome amps... However, depending upon the speakers you are using, the amps that they are suggesting might not be loud enough.... What other audio equipment are you putting into the boat?

At their sugestion, one amp will be running one pair or WS PRO 60's. The other will power 6 WS XS650's in the boat off of two channels, and a 10 in sub off the remaining two bridged channels.

Patrick, where did you order the Candence amps from? Also, I think I saw your boat at their shop yesterday, or one exactly like it.

(Message edited by brian_young on March 27, 2008)

It sounds like you're missing an amp. The 300.4 will do 350x2 at 4ohms which is perfect for the tower speakers. It sounds like for the cabin you'll be using a 900.6 which again should be perfect for the XS650s and a sub. I just got done with a very similar project.

Everything but the amps

KS900.6

KS300.4

KS300.4

Paul enjoying his new home

KS900.6 installed

KS900.6 installed

Pro 485s

XS650

XS650

XS650 versus Clarion CM1632

XS650 versus Clarion CM1632

XS650 versus Clarion CM1632


I didn't get a chance to get a picture of the WS420 installed but it works great.


Next up is to get rid of the Clarion tweeters.

Brian, that was my boat. I hope to get it back this week. PM me and I will give you the detail on the amps.

Evil, I'm positive he told me 2 of the 300.4. I was thinking I would need another amp for the sub, but my knowledge on the subject is limited.

Do the 900.6. I have the Front channels at 4 ohm for the front XS650, the rear channel for the other 2 pairs of XS650s at 2 ohm and the sub is getting 550 watts at 4 ohms from the last two channels. That is a great way of doing it. If you're going to run 3 pairs of XS650s off the front of the 300.4 and the sub off of the back it won't be nearly as nice.

Evil, thanks for the advise, but I’m sure the 900.6 is significantly more expensive than the 300.4. I’m looking for a more economical solution, not to spend even more money on a larger Arc amp. Did you obtain yours from a local stereo shop, I have not seen Arc online anywhere?

That 300.4 is doable for 6 cabin speakers and 1 10" sub, but not the most ideal. If wired right, you will have about 2.6 ohms with 3 speakers per chnl, each speaker seeing about 58W's. A little under powered, but ok.

Mike,

How do you figure the ohms and wattage at each speaker? Is there a calculator somewhere on the net, I can't find it? This amp research is quickly getting old.

Brian, the watts output is easy, any time you run multiple drivers on 1 channel, they will divide the watts output based on the ohms (impedance) load In your case, you will be near the 2ohm load and the amp will put out about 175W. Split this among the 3 speakers.

To wire the 3 speakers, you will need to wire 2 of the 3 in series, and then wire that pair in parallel with the 3rd. I cheated and used a calculator to give me the 2.6ohms. The W/S 650's are 4ohm drivers. (work smart, not hard )

You can find some good info @ www.the12v.com