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dpolen
02-02-2009, 04:46 PM
With Circuit City closing its doors, I stopped by this weekend and picked up a couple goodies to enhance my stereo in my Maristar.

I want to keep things on the cheap and simple. I already have Polk DB651's (6.5") in the bow with DB691's (6x9) in the cockpit. I'd like to add a second set of 651's to the cockpit and another set of 651's to be used as cheap tower speakers with some empty can's I'll buy on ebay. I bought a MTX Jackhammer 50 x 2 AMP to run the tower speakers. Lastly, I bought a new Sony headunit with 52x4 RMS power.

Can someone with stereo install experience tell me if the setup diagram I've got below makes sense? I'm thinking I'll run the bow and cockpit 651's in parallel and run everything else direct. Will this work, or is there a better way of doing this? I'm not looking for the killer sound system, just trying to up my game based on what I've currently got.

Thanks!
Doug

jgarner
02-02-2009, 06:55 PM
Actually, the way you have it designed you are running the speakers in series. That is effectively doubled the ohm rating for the speakers.

TallRedRider
02-02-2009, 07:20 PM
Actually, the way you have it designed you are running the speakers in series. That is effectively doubled the ohm rating for the speakers.

Correct. You need to have both positives together and both negatives together to get them in parallel like you want.

I have not heard much of people putting stuff off of a non-amplifier in parallel. It might could be done, but I don't hear of it much.

bturner2
02-02-2009, 08:34 PM
You really want to watch adding speakers in parrallel also. If my Ohm's law memory is still correct you will effectively decrease the resistance of each speaker in the parrallel circuit by half and increse current through them. This wasn't that big of a deal in the old days when speakers were 8 ohms but a lot of speakers are now 4 ohms. Good way to fry the amp in your head unit. Unless that head unit is made for this type configuration. I would consider doing it right the first time and see about getting a 4 channel amp.

dpolen
02-02-2009, 09:15 PM
So something like this diagram might really be the right thing to do?

Big Dogg
02-04-2009, 04:14 AM
For optimal sound performance make sure you keep in mind the RMS values of your speakers and of your amplifiers. For instance, I have a Sony 52x4 head, however 52 watts is its max watt output per channel, however RMS is more like 18 watts per channel. Those Polk DB651s have RMS values of (off the top of my head) 60-80 (I may be wrong)while the peak is around 150 watts. I know your not looking to blast sound and be the loudest on the lake, but I would most definately consider using at least a 2 amp setup (1 for the tower, 1 for the cockpit) that has the appropriate power ratings. Amplifying your speakers off the head unit is very feasible, however, your will be underpowering them (which can cause damage) and they will not be as clear when running at high volume. Its better to slighlty overpower speakers than underpower them. Trust me in saying, its better off to "do" your system right the first time, than have to do it twice. I am learning the hard way and spending about a grand more now just to fix what I thought I would "get by with" in the past because I didnt want it very loud. Just a suggestion, word of advice, and technical specification to consider.

bturner2
02-04-2009, 09:27 AM
If I'm looking at this correctly, the second diagram will work if you have enough pre amp outputs from your head unit. I'm assuming that you'll be running the four 6.5" speakers from the four amplified channels from the head unit. This would mean that you'll need 4 additional pre amp channels to feed the 2 amps.

Big Dogg
02-04-2009, 11:56 AM
You can achieve your additional amp outputs from your head unit by using RCA splitters. You are essentually splitting a signal not a power source, so you will not be losing anything.

dpolen
02-05-2009, 07:30 PM
If I'm looking at this correctly, the second diagram will work if you have enough pre amp outputs from your head unit. I'm assuming that you'll be running the four 6.5" speakers from the four amplified channels from the head unit. This would mean that you'll need 4 additional pre amp channels to feed the 2 amps.

I've got 3 RCA pre-outputs coming from my headunit, (Front, Rear, Subwoofer). I'm assuming that the subwoofer pre-out has some type of filter on it to prevent me from using this as the output for the tower speakers. I'll try it out, but will probably just have to use a splitter for a 2nd amp.

Does anyone have an opinion on Fusion Tower speakers, more specifically these that I've found on ebay? Seems like a pretty good deal, smaller speaker, but like I said, I'm trying to do this economical. I was just going to put my new set of Polk 651's in some empty cans on Ebay for about $150 including shipping, but for $50 more, these appear to be nice...I just don't know much about this manufacturer.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=220324293663

Any suggestions on a decent, CHEAP 4 channel amp I could use to power all the speakers I've noted above minus the tower speakers? Walmart has a 4 channel Sony for under a hundred bucks...it's been so long since I've done anything stereo related, I figured some of you might be able to steer me in the right direction.

Big Dogg
02-05-2009, 11:46 PM
I bought a set of Fusion T-series Combo speakers off ebay a couple of weeks ago. These are the combined 6.5 component and 5.25 coaxial. I paid 400 for mine, which is a steal, considered they MSRPed for 1200. The reason for the discounted prices is that Fusion went bankrupt, and they are closing out their remaining inventory. I just recieved mine two weeks ago and the transaction was great, price was good, and shipping was free. Being in Illinois, my boat is still winterized and I am unable to give them a try until April. I have a friend with a Supra, who has this same setup on his boat, and they are very loud, both behind the boat and around the boat. They are not Wetsounds, however, they are clear and consistant without being sharp or bright (high) sounding. A dealer in the area that used to sell Fusion swears by them, (he also deals in wetsounds) and without talking to their audio guy, one of the salesmen said from what he hears, his ears like the fusions better. Keeping that in mind, I dont know exactly which set you are looking at, I didnt look at your posting. However, I am very pleased with mine, even though I have heard them yet. In the past, their was issued with some of the chrome areas bubbling or popping, and I cannot say that problem has been fixed, but it is something to consider. I keep mine covered while trailering, so I am not worried. I would recommend amping them to at least 75% of peak. My combos max at 200 watts put unit, and I will be amping them with a JL Audio 300/2, puts out 150 watts RMS at 2-4ohms. Hope this helps!

bturner2
02-06-2009, 07:55 AM
You may want to look at Ebay or SonicElectornix for your amp. Sonic had a couple marine rated amps for $99 there plus shipping. Is has been the cheapest place I've found so far on a regular bassis for audio gear.

http://www.sonicelectronix.com/cat_i182_marine-audio-amplifiers.html