Boat Stereo/Battery Upgrades

[Mainah]

So I did a little reading this morning. I do not belive mathematically amp hour equal 6v and 12v batteries perform differently. That said I did figure out the difference and why some people go with 6 volt batteries.

A top of the line 12v group 31 AGM weighs 70 lbs and as 105 amp hours or 1.50 amp hous per pound. A top of the line 6v flooded deep cycle weighs 66 lbs and has 117.5 amp hous (235/2 to equal things out) or 1.78 amp hours per pound. So yes pound for pound in this comparison the 6v is 16% more efficient.

So why is this? Cell size matters. You can only make batteries so big before they become too heavy for an average person to lift into position and they have to be shipped. With a 12 volt this means you need 6 cells and having seperate cells takes up space and leaves less room for electrolye. The 6 volt has 3 huge cells and a larger cell has more room for electrolyte. A larger pool of electrolyte is also a bit more effecient at storing large amounts of electrons for high discharge.

So am I switching to 6v for my boat? Don't know yet. I need to look at the 6v AGM market has to offer for amp hours and footprint. Also my current setup is darn good and should last at least 5 more years. I still like the sealed AGM design when it comes to anything that moves or freezes.

When it comes to price @MattFX4 just posted on the deals thread that Sams Club has a good 12v group 31 agm on sale right now for 150 bucks. That is a great price.

 

[David Analog]

A couple of notes.
4-ohm versus 2-ohm efficiency? Not a tremendous amount of difference. Most unregulated amplifiers will deliver a premium in power at 2-ohms versus 4-ohms and some are even biased for a 2-ohm load. So with an unregulated amplifier a lower load generally offers more power (perhaps 40 to 60% more). Is their more wasteful heat generated at a lower impedance load when delivering more output power? Sure. The amplifier efficiency drops about 10%. Not exactly a game changer.
The SMD tuning device is good for finding the maximum non-clipping output. But for a balanced and good sounding system you are definitely not running ALL channels at the maximum safe output. So while the SMD device is very useful, it is only the first step in a far more complex tuning prescription.
Generalizing all audio dealers/installers with one label makes no sense. Sure, there are those dealers who aren't particularly competent. But on the flip side there are those dealers that are light years more evolved than any DIYer that have a half dozen systems under his belt. Those DIYers have yet to learn enough to know what they don't know.

 

[FloJet]

@Mainah to be honest I was confused when they explained it to at the stores. The battery reps stated something in the realm of how 3 cells operate more efficiency than 6 cells. Not sure what all that means. But so far this is what I have gathered in my research.

"The 6 volt battery has more space per cell than the 12 volt hybrid so the plates are thicker and will last longer. The 6 volt will be able to discharge deeper than any hybrid 12 volt deep cycle. Two 6 volt deep cycle batteries are a much better buy than two hybrid 12 volt batteries." Kinda subjective to me here. Now I did make a mistake quoting that 12v weighs less. Usually 6v can weigh 50-60lbs while 12v is around 80-110lbs. so my mistake but you quoted it right in your post.

I think your system is good to go since you are satisfy and already bought the equipment. I think for new owners or ones who are in the market for batteries, 6v is something they might want to consider especially if they have the new 24' boats as they have the space to accommodate. I haven't seen AGM 6v but would be curios about them or to see if they hold more value than the flooded 6v. I'm not a fan of adding water to my batteries but only have to do that 1 to 2 times a year. For some reason my 6v don't lose as much water as I did with the 12v. Another weird concept. Thanks for the update. I knew you would be on top of this to get us on the right track.

 

[FloJet]

@David I agree. But you have to realize at least in Oklahoma I have not heard a install shop that uses any tuning devices but they say rather by ear. I don't know about you, but I would rather use a tuning software/device to tune a system that you paid hard earn cash on vs someone telling you they tuned it by ear. I've had speakers blown because of those idiots. Another reason I do everything myself now. I have tuned my systems in both truck and boats by ear before but I promise you it's not comparable using a tuner. $150 to get close to my unclip values is way worth it than spending $ to replace equipment all the time. We play incredible loud music so I have to make sure my equipment can handle all that. Again with the tuner you still have to know what you are doing. My system is tuned with the SMD from my head unit to my equalizer to my amps. I know where everything clips starting from my head unit. With tuning by ear that's impossible to do for all those equipment. Greatest threat to any system is distortion/clipping. If you take that away you will have very less chance of damaging your equipment when it's pushed to the max. I'm running 750 watts to each speaker and that cannot be accomplished with by ear, especially trying to find the cross over zones to where things don't clip. 750 watts without the proper tuning procedures would fry your midbass/bass drivers in lets say a Rev410 rather quickly. So have to know how to compensate for that. I spend 10 hours just on that so you def have to be careful in doing so. lol

Now days I feel DIYers are sometimes better than these supposedly professional shops. Like I stated before, they hire no bodies to do installs and that's not cool by me. By no means I think every shop is like this, but the way they pay these installers sometimes, they have hard time keeping the professional ones around. Just my opinion on that. Some things I do myself and others like cutting into my boat, I leave that to the professionals. If my stereo cuts out while we are out in the water, I can troubleshoot it rather quickly than waiting for the work week to take my boat in to have system serviced and for them to tell me I need to spend more money. We DIY projects you know where the mistakes are when they arise IMO.

 

[FloJet]

Also going from 4 ohm to 2 ohm in unregulated amp sure gives you more power at the expense of power consumption. Anytime you double the power, you increase the draw. Now if i have a sub that utilizes 2 ohms obviously that's the route I want to take but why buy unregulated amp when I can get a more stable one at 2 ohm. But to take it farther, lets say kicker amp has 4 ohms stable at 600 watts while you get 1200 watts at 2 ohms. Don't make sense to use that when I can get a 1200 watt stable at 4ohms lets say JL HD versions and gives me the same power at 2ohms but less draw. It's no brainer there for me. Now off course $ and other factors can come to play in selecting a system but those HD Amps can be stable at almost any ohms. Why go away from that. Now boat speaker uses 2 ohms so why get your sub to run 2 ohm when you don't have to. I run 4 ohms in everything and it gives me incredible play time. If I could do 8 ohms that would be my choice, but we can't get speakers at that stable just yet or amps to accommodate that.

I am no means trying to bash any shops. For the longest time I was that person who paid for things to get done until I experienced flux of problems with most of my installs. When some boaters spend thousands on a system, I just don't think it's feasible for a shop to tell me my system will be finalized by ear. That's just not enough for my peace of mine. It can be done but for what I am trying to accomplish I would be limiting myself by doing that as I could not get max output from my all my equipment by setting them by ear.

 

[FloJet]

This is where I might be a little confused. I would have 4x210=840 in reserve capacity and just trying to convert the 470 amp hours into the the reserve capacity minutes?

When your group 29s are wired in parallel, you will double the reserve capacity. Some rate batteries by 20 hours while others do 25 hours depending on manufacture. so yes yours would be 840 amp hours for either 20 or 25 hour draws. Doesn't mean that's what you will get in the real world. You would be drawing more power than what they tested these batteries at. Your setup sounds great and I don't think you need to change if you are ok with how it runs. I try not to look too hard into the numbers for stereo applications as you will not draw the same constant power. So it's hard to determine how much you can run for on them. But 4 12v vs the 4 6v route. You will find it more play time with the 6v because it can be discharge slower and for the reasons stated before run more efficient for these types of applications we are seeking.

 

[David Analog]

A sine wave test tone should never be applied directly to a speaker at or near full power. So the SMD is effective at measuring a clipped signal at every point in the signal path except for the amplifier output as there can be an appreciable difference in the real power level with and without current flow. With an SMD you are measuring at voltage but with a very high termination impedance = no current. The SMD is a convenient tool but just a starting point in a system tuning sequence. Once finished with the SMD, you must rely on your ear. I'm not a pro, but I have many friends who are pros and have thousands upon thousands invested in sophisticated test and measurement equipment. They always finish by ear.

 

[Mainah]

@FloJet - Keep in mind my comparison is AGM vs. true 6v flooded deep cycle. Hybrid marine batteries are not AGM and are a whole different animal that are only good for starting the boat and playing a stock head unit and a few speakers, then needing replaced in a couple of years IMO.

True deep cycle big enough to start the boat or AGM is the way to go for big systems or longevity of the battery. My only issue and it is a ratther big one with the true flooded deep cycle is maintaining the electrolyte. If one forgets and the plates become exposed to air then the plates start to sulfate and significantly degrade the performance. Heat speeds up the gassing off process and our boats see plently of that. Spillage and keeping the battey at the correct acid mixture are also issues that can arise. If not for those factors I would recommend just as you have. Given those factors I will modify my future recommendations to include both agm and 6v deep cyle and cover the pros and cons of both.

 

[FloJet]

@Mainah I agree with you with AGM. I would love to go that route as I am the one who sometimes forget to check water levels and all. AGM gives me freedom of that. I just don't know if the AGM 6v are cost effective vs 6v flooded. I don't think I've seen any AGM or any cheap ones at least.

 

[David Analog]

Whether a strictly regulated amplifier, or an unregulated amplifier, if both are of equal topology (whether Class D or other) the amplifier efficiency will be the same, or too similar to be of issue, at both 4-ohm compared to 4-ohm, and 2-ohm compared to 2-ohm loads. I'm a big, big fan of JL Audio HD amplifiers. And I happen to know how they work.
Also, if an amplifier, any amplifier, strictly regulated or unregulated, delivers more power at 2-ohms versus 4-ohms, of course it draws more current at a higher power level. Run both scenarios at the identical power level, regardless of termination impedance, and the current draw is too similar to make an issue of.

 

[FloJet]

A sine wave test tone should never be applied directly to a speaker at or near full power. So the SMD is effective at measuring a clipped signal at every point in the signal path except for the amplifier output as there can be an appreciable difference in the real power level with and without current flow. With an SMD you are measuring at voltage but with a very high termination impedance = no current. The SMD is a convenient tool but just a starting point in a system tuning sequence. Once finished with the SMD, you must rely on your ear. I'm not a pro, but I have many friends who are pros and have thousands upon thousands invested in sophisticated test and measurement equipment. They always finish by ear.

I agree @ david. But with the SMD tuner, you do not test or tune it while the speakers are hooked up. My whole system was tuned before I heard a sound. It's not about the sound, it's about the distortion points. Yes when you play music you have to compensate for what you are listening to but that's where the equalizer and a good headunit comes to play. So with volume at full unclip volume with speakers disconnected you can use SINE wave to get you there.

Again there are great professionals out there that can tune systems all day without any tuner. I just prefer not to use those guys on something I care so much about. My SMD route is way safer than their route. This now becomes technical. Without the tuner you don't know where you MAX headunit ouput is without clipping. That alone got an individual starting out without maxing out their stereo potential. I want my monies worth when I set my stereo.

Knowing your max HU output makes it where the equalizer and amp don't have to be turned up too much to match the voltage coming from the head unit. I do the same for the equalizer which in terms help protect my amp so I don't turn it up more than need to. Sorry but the pros can't do that by ear. Sure I guess they can if they run just interior speakers hooked up to an amp but now it becomes a whole different technical game. Tuning is all about matching voltage on all stages, No dis respect to you or any shop but that can't be accomplished by ear. With with multi meter or tuner. Only way IMO. Pros def can tune a system and have them sounding very sweet, but without any digital tuning off some sort, some meat is left behind regardless of what they say or sometimes too much meat is added to it.

 

[Mainah]

@Mainah I agree with you with AGM. I would love to go that route as I am the one who sometimes forget to check water levels and all. AGM gives me freedom of that. I just don't know if the AGM 6v are cost effective vs 6v flooded. I don't think I've seen any AGM or any cheap ones at least.

Agreed AGM are in general are more expensive up front but forgetting to top off electrolyte and test with a hydrometer can cause the long term cost to be greater the other way around in needing to replace a battery. Both are great at what they are designed for and to each his/her own on making an informed decision that works for them. Kind of like investing that way. Lots of choices with no one way that fits all.

 

[FloJet]

Whether a strictly regulated amplifier, or an unregulated amplifier, if both are of equal topology (whether Class D or other) the amplifier efficiency will be the same, or too similar to be of issue, at both 4-ohm compared to 4-ohm, and 2-ohm compared to 2-ohm loads. I'm a big, big fan of JL Audio HD amplifiers. And I happen to know how they work.
Also, if an amplifier, any amplifier, strictly regulated or unregulated, delivers more power at 2-ohms versus 4-ohms, of course it draws more current at a higher power level. Run both scenarios at the identical power level, regardless of termination impedance, and the current draw is too similar to make an issue of.

Yes you are right about that in both scenarios. But in those situations with amps now days, 4 ohms will consume less than 2 ohms with the same power intentions. Not about the raw numbers here again but what has been experienced in real time. Another reason I went away from utilizing anything less than 4 ohms. With those JL HD no sense to go to 2 ohms unless your subs only handle that. But if you can get subs to be wired in 4 ohm or 2 ohms, 4 ohms is better in this scenario as it's little more efficiency in terms of power consumption.

 

[FloJet]

Agreed AGM are in general are more expensive up front but forgetting to top off electrolyte and test with a hydrometer can cause the long term cost to be greater the other way around in needing to replace a battery. Both are great at what they are designed for and to each his/her own on making an informed decision that works for them. Kind of like investing that way. Lots of choices with no one way that fits all.

Def agree. When I can get AGM 6v for a reasonable price that's the route I will def take unless something else better comes along.

 

[FloJet]

This is why I love this forum. So many people have different ways of doing things and very interesting learning about it all. But I just think for the new owners out there that are trying to get more from their systems, I try to not get bias but only present what I have experienced than they can make their own decisions from there. The best boat system I've heard out here has over $40k put into. But sorry tuning that much by ear is just plain crazy. He knows the only safe route is a professional digital tuner to protect his investments. Oh and he owns his own custom shop so he is probably one of the only few I would let him touch my radio. As the saying goes, don't touch another men's radio We all learned the hard way out here. I can blast and make ear bleed only cause I used a SMD tuner. If I had more money, I would buy the more expensive tuners to really get more out of it. Hahaha.

 

[David Analog]

Also going from 4 ohm to 2 ohm in unregulated amp sure gives you more power at the expense of power consumption. Anytime you double the power, you increase the draw. Now if i have a sub that utilizes 2 ohms obviously that's the route I want to take but why buy unregulated amp when I can get a more stable one at 2 ohm. But to take it farther, lets say kicker amp has 4 ohms stable at 600 watts while you get 1200 watts at 2 ohms. Don't make sense to use that when I can get a 1200 watt stable at 4ohms lets say JL HD versions and gives me the same power at 2ohms but less draw. It's no brainer there for me. Now off course $ and other factors can come to play in selecting a system but those HD Amps can be stable at almost any ohms. Why go away from that. Now boat speaker uses 2 ohms so why get your sub to run 2 ohm when you don't have to. I run 4 ohms in everything and it gives me incredible play time. If I could do 8 ohms that would be my choice, but we can't get speakers at that stable just yet or amps to accommodate that.

I am no means trying to bash any shops. For the longest time I was that person who paid for things to get done until I experienced flux of problems with most of my installs. When some boaters spend thousands on a system, I just don't think it's feasible for a shop to tell me my system will be finalized by ear. That's just not enough for my peace of mine. It can be done but for what I am trying to accomplish I would be limiting myself by doing that as I could not get max output from my all my equipment by setting them by ear.

Of course there are other methods, even if you are unfamiliar with them. A continuous sine wave in no way emulates a transient and complex music signal. Your sine wave test tone at 0 dB or - 5 dB, may or may not reflect the level of your true music source. A measurement without current can be off substantially at the output terminals of an amplifier. While your method is a good route for you, it is not the ultimate method for everyone. Also, you can tune any system any way you want....but that is no guarantee that a good tune won't be circumvented by the end-user via different source material or equalization, whether that equalization is introduced within a download or at the playback source. And just scratching the surface.

 

[FloJet]

@David Analog

I have no argument there. You have me beat this round. But this is just a start for others. I understand the importance of getting clean signals in all channels from my phone, phone app, to headunit, to equalizer, to amp. I only tune with 0 db as that is truly the safest sine wave for all music as it's more neutral. I listen to lots of bass so anything above that creates clip/distortion. Yes a beginner would not know all this. Hence why no one is allowed to play anything on my system unless its through my phone app that is tuned for. I can play music through my Aux line out but my system is not tuned for that so I wouldn't play music very loud that route. Way more little details to play with to tune a system that can't all be covered in a forum. I can tell you where everything starts to clip on my system on all cross over points. I know my sub amp clips at 85 cross over point so I know how to avoid that. The kind of loudness we try to achieve, you can't just set the amp and think you are good. Shoot I spent almost half a day on just the equalizer before I even hooked my amp up, so more technicality involved in all this so this is just not for the beginner and I understand that. But I do promise you for how loud I get my system and over clock them, you will not be able to set it that way it by ear atleast without damaging the equipment at some point. Very hard to match all voltage points hence the main advantage of tuning a system to get voltage to match as much as possible to the headunit. Without a multi meter or tuner cannot be accomplished to full potential IMO.

Have a friend or someone who has lots and lots of money buy Rev410 put 750 watts to it, tuned by ear and played loud, and it wont come close to where a tuner can get it. Plus you risk damaging the HCLD in them without knowing how to compensate for some other factors involved. That's why most only use 350 to 400 watts on these midbass drivers. Owner of WS Tim uses 1000 watts to each rev410 and I don't care how many speakers you have, it can't touch it without sacrificing other things. But he also spent over 30 hours tuning it. And I tell you it was not tuned by ear.

 

[Mainah]

A test tone generator app on your phone, a multi meter and some math can do pretty much the same thing as an SMD in the right hands. A SMD does not however do what an oscilloscope, a microphone and other sophisticated equipment can do in the right hands.

Finishing by ear is almost always needed to balance things out so the music sounds to the ear the way you want it to. Being sonically perfect to equipment and sounding how you want it to are two different things. I like my music a bit mid bass heavy. I also have hearing damage so what sounds good to me may be different to others.

Bottom line is if you want to do it yourself then understanding the principles behind it goes a long ways but not all the way. If hiring someone then find someone with many years of experience that has a stellar reputation. All the fancy equipment in the world does not make up for lack of knowledge or experience of the operator.

 

[FloJet]

All I can say with tuners and multimeters is, you cannot get voltage to match in 2 or more equipment just by ear. Sure it can be done and be close but not the scientific logic way it needs to be by getting the true readings. If HU puts out 2.6 volts, hard to get equalizer and amp to match that without know what voltage the amp or equalizer is producing.

 

[FloJet]

A test tone generator app on your phone, a multi meter and some math can do pretty much the same thing as an SMD in the right hands. A SMD does not however do what an oscilloscope, a microphone and other sophisticated equipment can do in the right hands.

Finishing by ear is almost always needed to balance things out so the music sounds to the ear the way you want it to. Being sonically perfect to equipment and sounding how you want it to are two different things. I like my music a bit mid bass heavy. I also have hearing damage so what sounds good to me may be different to others.

Bottom line is if you want to do it yourself then understanding the principles behind it goes a long ways but not all the way. If hiring someone then find someone with many years of experience that has a stellar reputation. All the fancy equipment in the world does not make up for lack of knowledge or experience of the operator.

Now your talking. I agree @Mainah. But some are not good with that kind of math lol. SMD takes that equation out. OSCILLOSCOPE hands down is the best way but I don't have such $ to get one. So SMD or multimeter is your next bet. Now don't get me wrong yes all my music is always set by ear when playing. Hence where the WS 420 equalizer comes to play. I can make the adjustments per the music. But my voltage is matched on all equipment before any of that can take place or I will be shorting myself of ouput. That keeps distortion/clipping very low which my equipment thanks me for.

Again I will never disrespect any professional installers out there. I just know for peace of mind, I don't want thousands of equipment being set by ear only. That's like me building a computer and testing everything by sight and ears only. Can be done just not as effective as using something digital to give you concrete info. Same installers setting my system by ear will NOT produce same output as doing it with something digital. Just my honest opinion here.