Final sound selection on sound system

[Coach]

At max output @ 14.4 volts in a 5 channel 4 ohm, the XA5000 will pull probably (this is estimating) 25-30A....
At max output @ 14.4 volts, the XA4000 in a 2channel 4ohm will pull 25-30A depending on the internal rail voltage, etc....

The XA5000 will need to produce 36A, and the 4000 49A to go max output, but I am sure there are some step up circuits in there.

All in all, figure them pulling 60A total at max power........big bass note....huge snare hit, and you only have 5A left on that 65A alternator....that is a huge current draw, and is bad on them.....you might want to upgrade at the end of the season next year, or start saving for one. It will make a difference in the sound you get out of your sub, and it will help the amps from clipping as they try to get more power. Undersupplying an amp will cause it to clip.

Some people will tell you to "just get a cap" or a capacitor. If an installer tells you that, go elsewhere. A cap is like a band-aid, water tank. It will store energy and release it when the amp draws some amperage, but you then need to fill it back up......it doesn't really solve the problem which in this case would be lack of flow. If you think of the electrical system as a water system, it will make more sense. Batteries are like huge storage tanks, but they only help the system run longer with the faucet off. They will also allow some output to trickle out as the pressure gets low, but they have to be refilled. A marine (deep cycle) is a very large tank with a small faucet that can be emptied over, and over; a starting battery is a very large tank with a very large faucet, that doesn't like to get emptied alot....it starts to lose capacity over time. A cap is like a mini-storage tank with a huge faucet on it. It can release a little water flow, really quickly, but it also has to be refilled. The thing doing all the filling is the alternator. The bigger the main faucet, the better your pressure will be.

Still the most important area of a big boat stereo is the batteries. The Alterantor will help but will never get the batteries back to charge unless you are running your boat for 8+ hours a day. Plus most stock Alterantors 60-90 Amps will not cut it. Another problem with the way Alt delever the charge which is a huge bulk charge all the time no matter the amount of drain on the battery. I looked into doing a 200 Amp alt with a Balmar charging system which will smart charge the batteries and help top of my starting battery. Total cost is over $2000 to do it. The main problem I found is the CPU's in the boats don't know what to do with extra charge and it will create some problems with the computer system in your boat. You can add a second Alt which will supply more charge to the batteries while not bothering the CPU but it will require some good alignment on the pully system and new pullies. I have gone around and around with this issue. I have even though about a Honda 2000ie generator in the rear compartment with the exhaust going out a new bilge hole hooked up to a power coverter (many hotboaters do this), but for saftey and cost still is not the way I want to go yet. For now I am going to have an onboard charging system that I will hook up each night to bring the batteries back up to full charge. The Alt can help top off each day, but the 3 odyessy 2150's I will be running should handle the load each day. Just some thoughts.

[Jeff T]

For now I am going to have an onboard charging system that I will hook up each night to bring the batteries back up to full charge.

I'm listening. Maybe another post on this one?

[Lucky 275]

Jeff T

I've got one, I screwed it to the Battery compartment hatch door, works well.

http://www.basspro.com/servlet/catal...=SearchResults

[spharis]

Still the most important area of a big boat stereo is the batteries. The Alterantor will help but will never get the batteries back to charge unless you are running your boat for 8+ hours a day.

If your boat is running the stereo is running on the amperage supplied by the alternator. More batteries only help you if your engine is off, except in extreme cases where the system draws more than the supplied amperage, and pulls from the battery supply....think the previous post of a storage tank.

Autosound 2000’s First Three Rules of Basic Automotive Electronics as applied to normal car audio installations:

1. The fundamental purpose of a car battery is to start the engine.

2. The fundamental function of the alternator is to charge the battery and run all of the car’s electrical accessories — including the stereo system.

3. The fundamental reason to install a second car battery is to increase the engine off, parking lot listening time for the stereo system.

Conspicuously missing from the above three rules are claims that extra batteries improve the sound of the stereo system, prevent headlights from dimming on deep bass hits, and lighten the load on the alternator. Although SPL vehicles often require huge battery banks, extra batteries do not improve the sound for normal installations. Adding an extra battery will not prevent headlights from dimming. And adding an extra battery actually increases the load on the alternator, thereby leaving less available energy for the stereo system. Whew!

Another problem with the way Alt delever the charge which is a huge bulk charge all the time no matter the amount of drain on the battery. I looked into doing a 200 Amp alt with a Balmar charging system which will smart charge the batteries and help top of my starting battery. Total cost is over $2000 to do it. The main problem I found is the CPU's in the boats don't know what to do with extra charge and it will create some problems with the computer system in your boat. You can add a second Alt which will supply more charge to the batteries while not bothering the CPU but it will require some good alignment on the pully system and new pullies. I have gone around and around with this issue.

A huge bulk charge is exactly what you want. The alternator is internally regulated in most cases, and will stop charging once it is no longer excited. Once it becomes excited again, it will charge again.

Unless Tige' has reinvented the way the charging system works....the cpu has absolutely nothing to do with an alternator supplying amperage to the electrical system. The is a primary function of the regulator in the alternator. The alternator senses the overall electrical system power, and regulates itself to deliver a smooth 13.3-14.4 volts to it. If it goes over that, you have issues other than the alternator. You can have a 500A alternator powering a single LED, and you will have no issues. It will remain at 14.4. Alternators are usually connected to an ignition hot if they require exciting, and straight to the battery.

Adding a second alternator accomplishes nothing that a higher output alternator can't, except for making you spend way more cash than you should. The end result is the same, higher amperage being supplied to the electrical system(Again think water, and the alt is the supply faucet. Two faucets 1/2" line = a single of 1"). In many cases where a second alternator is added, it is in an isolated multiple battery situation, or in very high amperage applicaitons where you need extremely high out alts.

As far as charging time....a single 60A alternator can bring a battery with 750CCA up to enough power to start the engine in under 10 minutes. Very low output alteernator will take hours to charge.....a 60-90A will do a full charge in minutes.

A comparison is a battery charger. It charges at very low amperage, probably 5A. You are looking at 6 hours on that. You are better off upgrading your alt and getting a trickle charger vs. doing a generator install unless you plan on being without the engine running for extended periods of time, and requiring constant power.

Trickle Charging:
With 1 to 3 amps, charges small batteries in two to 12 hours.* Also, keeps large batteries topped off or warm in winter for easier starts.

Medium Charging:
With 4 to 8 amps, charges a battery in six to eight hours.*

Fast Charging:
With 10 to 15 amps, charges a battery in three to five hours.* The higher the amperage, the less time it takes to charge.

Rapid Charging:
With 20 to 60 amps, charges a battery in one to three hours.*

Engine Start:
With 50 to 300 amps, supplies a battery with sufficient power to crank an engine within minutes. Higher amperages mean greater starting power.

*Charge time is based on the battery having a 50% charge level before charging. Courtesy of Schumacher Electric.

[chpthril]

I dont think the power drain problem is as bad as you think?
Correct me if I'm wrong, but we are talking about a system drawing 60amps(example above) at full or near full volume right How long do you'll run the volume wide open!!!!! I know I'm not pulling peak amps from dock to dock.

When the tunes are turned down, the Alt will have an opertunity to bring the battery(s) back up. I think that adding 1 or 2 deeps, especially with a 90amp alt, would be able to handle this.

Alternators have regulators that very the output based on demand, this provents damage to electrical componants and overcharging. If the alt is charging at or near its rated max output all the time, then the Reg is faulty or it's time to upgrade the Alt.

If you have access to an Amp probe, then you can read the true drain on the alt/batt system and also see if your Alt is running at or near peak. Armed with this info, then you can make the right mod without over/under doing it, money and parts.

[spharis]

The power drain isn't bad, but it is present. I don't like watching my gauges droop when a bass note hits, my lights dim when the radio is playing, or the gauges nearly turn off when the TAPs is being adjusted. I do not like to stress my electrical components, and having an underpowered charging system does this.

Example:
You just dropped $1400 on a sound system for your boat. It pulls 45A at a moderate volume. You also have your lights on, your ipod plugged, adjusting your wake plate, etc, etc......

All of the sudden one of your amps turns off.....after a while it comes back on.....again, the sound gets distorted, and the amp turns off.....

While it may be annoying, it could also have the potential to damage that $1400 stereo system. An underpowered amp sending a clipped signal to a speaker will burn it just as fast as overpowered ones.

I like my stuff to be tip top, so having a powerful reliable charging system is a great start. Putting all the stereo on a small alt is like supercharging a lawnmower engine to me.......

In Moki's case, a higher output alternator is a given......you build your system to a certain spec....in his case RMS output (as al systems should be spec'd). So make sure the charging system can handle it. A 60A draw on a 65A alt is a bit much, and his amps will clip at high volume with the engine running regardless of how meticulous he matched the gains.....I almost guarantee it.

Now chilling at the beach/dock jamming some tunes, no problems....but if your engine is running, you are running off that alt.

When the tunes are turned down, the Alt will have an opertunity to bring the battery(s) back up. I think that adding 1 or 2 deeps, especially with a 90amp alt, would be able to handle this.

What if both of those deeps are at 3V because someone left the bilge pump on all night. Personally, I would do 45A per battery.

If the alt is charging at or near its rated max output all the time, then the Reg is faulty or it's time to upgrade the Alt.

confirmation....65A - 60A = alternator running at max most of the time = premature failure = upgrade that thing.

Again like you said.....this isn't a doomsday thing, more of an annoyance, but it is something to keep in mind. When considering seasonal upgrades....also think about the onboard charging system. One that runs max all the time will wear out, and your electrical components will like you alot more too.

[Coach]

Spharis-
I guess it depends upon the use of the stereo. If you only play it while running or floating for short times the Alternator will work fine, but and upgrade to a 90 Amp would be the way Moki needs to go. If not the 65 Amp would, like you said only supply a 5 Amp charge back which would delay the batterires from running down. I spend a lot of time beached and cranking the tunes. I found that the standard Alt will not get them back to a full state after I run them down that low. I guess with what I have read about an Alternator is that they help maintain the battery level but are not really a charging device per se. It can damage a batteries life over the couse of time was my understanding. This is the one area when it comes to stereo's that sucks. There is so many differing opions on how to charge and what is good and what is bad. From everything I have read the best is still using a charger on the batteries to get the max life out of them. I inquired about doing a larger Alt 200 Amp with the Balmar charging system with Wired for Sound in Murrietta and they would not do it because they found it created problems with the new boats computers. By no means am I any expert on this stuff I just read and try to come up with a good solution. Thanks for all of the good input on this, it is by far one of the most confusing topics.

[dogbert]

I'd get a charger that handles multiple batteries regardless of your alternator. It will help keep your batteries fresh when you want to use them.