sub is cutting off at high volume, help

OK, got my system installed last Friday and it's HUGE! I have four speakers in the boat running on a JL 4350, six tower speakers running on JL 6450, one JL 13W6V2 sub in a downfire box running on a JL 1000/1 amp. I have a two battery setup, they are interstate marine cranking batteries. Stinger SR200 isolator. The deck is still powered off the main battery but everything else runs off the second, radio battery. It is carrying a constent 13V so no battery issues. But at high volumes the Sub quits playing when you turn the volume back down it starts back up. Anyone had this issue and how did you overcome it?

Thanks for your responses,
Ken

My guess.....something in your batteries. What's probably happening is at loud volumes your amps are pulling their highest currents...the sub amp will pull it's max on deep bass hits. Even thoguht class d amps are more effecient a 1000 watt amp will pull some seriuos power on big hits. the starting batteries your using may not be able to handle the sudden current draws???? Just a thought.

is power being lost to the amp or the sub is just sutting out? does yrou whoel system cut out too?

a recent issue a friend had was a similar scenario but was nto as clear as he coudl have been when descibing the problem....his sub was causing his cd player to skip thus the "cutting" out of his sub.

I have the same problem in my 05' x-45 with Factory stereo. I would think that the amps can't handle the load, so the have Safety cut off. But, not sure. If anyone else knows what it is, let me know. I doubt if it is a battery problem, you would see a huge draw off of the ampere meter, which I do not see on mine. I think it is an amp issue.

I have run the JL 1000/1...They suck batteries dry. They require a lot of power. Sounds like it is clipping and pulling too much battery power at one time. Marine cranking batteries are not stereo batteries and may not be able to keep up with the power requirements of the JL 1000/1. Just a thought...but my opinion means little.

Everything else plays constent just the sub cuts. I know some people use golf cart batteries for something but I'm not sure if I need to get different batteries or not. I don't mind as long as it fixes the issue! We like to part and listen to the radio for a couple hours between rides so it's something that I need to address as well as it being a big annoyance

Ken:

A comment you made have me puzzled:

"It is carrying a constent 13V so no battery issues"

How are you getting a constant 13 volts?

A fully charged battery at rest will be ~12.6 volts. If the amps are cranking out a thousand watts or more I would expect the battery voltage to drop as low as 11.5 volts, measured at the battery. There will be additional voltage drops getting to the amps so if you measure at the amps you might only see 11 volts.

If the engine is running then the alternator will help out some. With the amps off I would expect to see 13.2 to 14.1 volts. Depending on the size of the alternator and the engine RPM the full volume voltage could still sag to 11.5 volts!

Does the sub shut down immediatly when the volume gets high, or will it carry it for a little while? If it shuts down immediatly then I would expect that it is a voltage issue. If it plays for a couple of minutes and then shuts down it could be a heat issue.

A reasonable quality amp will have self protection for under voltage and over heat conditions. If the main power cables are too small of a gauge or too long then the voltage drop will be a problem. If the amps are tucked into a spot where they don't get any air flow then they could easily be overheating.

The worst thing for an amplifier, heat wise, is to have them fastened down to the carpet. The carpet makes a very nice thermal blanket and keeps any air from gettting to the bottom of the amp. The best thing is to have the amps mounted to a hard, smooth vertical surface that will allow air to flow on all sides.

If the problem is heat then you might want to try spacing the amps off the mounts a little (add spacers) to provide air flow underneath and add a fan to blow air over the amps. A four inch box fan powered off the amp remote wire would help out a lot.

What size wire are you using between the battery and the amps? If you are not running at least 4 awg then I would bet that is the problem. I would recommend 2 awg from the battery to a distribution point and then fan out to each amp with 4 awg.

Moving the battery closer to the amp might help, but changing the type of battery (golf cart, AGM, etc) won't.

Rod, thanks for chiming in. I'm just checking with a volt meter while the system is off. I've got the wires as you mention above but 4 awg to everything. The people that put this in are the best in car stereo in the area so they hooked it up right, I'm thinking. All amps set on their own fabricated sled that keeps them at least 2 inches off the carpet. The cutting off happens whether it's been playing for a while or if when I start playing it. It bumps hard at high volume then cuts off and will try to come back but then cut back off. If I turn the gains and the LP to off it does fine at high volumes so it very well might be the needed voltage to allow it to hit with the gains turned up to where they should be. For my hearing purposes maybe I should just leave the gains down because I'm sure to go deaf SOON ;0).

It sounds like a voltage drop...which is not good because that 1000/1 handles voltage from 11.1 to 14.5 if I remember correctly. So you are dropping your voltage pretty good when you are running that 13w7 hard. NEED MORE POWER!!!

Good Luck with the setup. I hope you get it figured out. I have had similar frusterating problems with my last boat and stereos.

When the sub cuts out is the amp going in to protection mode? IF so I'm with everyone else soudns liek a voltage issue, like rod said make sure you have the proper guage wire. I understand what a regulated power supply (j/l amps have them) does but don't understand the technical side of it. I still don't understand how the amp can still push the same power at lower voltages, w/o getting really hot or going into protection.

Don't mean to hijack, but what are the in's and out's of running the JL 1000/1 with say this sub? Is it practical with a stock alternator and 2 batteries? This assumes a reasonable amp setup for interior and tower speakers. Sorry again but i've been wondering about this for awhile. Matt

OK, by need more power are you recommending me to buy a higher-end battery? If so will the optima yellow tops work? As I understand, interstate sells these un-labbled but they are the same battery. Is there something I should note when looking for a different battery??? Thanks again.

Im with everybody else. My 1000/1 which currently only runs one 12w6 will shut itself off when my voltage gets in the 11 volt range. If I switch to the acc battery it fires right back to life. Its supposed to play at 11 volts but the big low end hits Im sure temp drops the voltage well below the 11v range sending the amp into protection mode.

How are they spliting the RCA signal to the three amplifiers?

Try disconnecting the remote lines on the JL 4350 and the JL 6450. Turn the volume back up and see if the sub still cuts out. This should tell you if it's a power starvation problem.

Ken- I dont think the type of battery is such a concern as much as how many amp hours are provided by your batteries. AGM style like Optima are nice for mounting reasons but there are cheaper wetcell batteries that supply more power. The key is to get a larger battery or combine batteries to supply the stereo with more power.

OK, what amp of a battery should I look at getting?

For everyone's 1000/1 that is shutting off, how many/size of batteries are you running? Sounds liek you don't have enough power to run the amp all day, asumming your wiring is ok. I run (2) j/l 500/1's to 3 subs and never haev issues like yours...I'm running golf cart batteries (equivalent amp hours to 4 ro so blue tops)

Coudl it be that b/c your using starting batteries and not deep cycle your batteries have been zapped down low so many times that they don't hold a charge for very long and therefore you get maybe 30/60 min of playtime (engine off) max then you run into low voltage issues?

I also like craigs theroy as a test.

New yellow tops will definitely help, with the setup you're running i'd recommend 2 yellows wired parallel for the stereo and a red or another yellow separated by the isolator. It sounds like it might be a mix of that and your gain settings...I'm having trouble grasping why you'd need ANY gain on a 1000/1 going to only 1 sub. The 500/1 would have cranked the bejesus out of that w6, and saved you a ton of cash, but since you've got the power, you should definitely be taking advantage of it by running the amp as cool as possible. So, for your solution, in this order:

1. Set the gains on your sub amp ONLY (Since the rest don't seem to be having problems) by using the guide here.

http://mobile.jlaudio.com/support_pages.php?page_id=143


2. If that does not fix the problem, upgrade your batteries, at least with a better stereo-specific battery, if not to the layout mentioned above.

3. If THAT doesn't work, upgrade your wiring to a thicker gauge...I can't imagine you needing this if you're running separate 4awg wires to each amp individually from the battery. That's a lot of fuses!


Good luck, let us know how it goes!

Something to keep in mind as well while you're going through the process of setting your gains; If your head unit is not powering any speakers off its internal amp and is using all RCA line-outs (This sounds like the case in your stereo) then any HU worth its salt will be able to be turned up to full volume and send the line-out signal without clipping. If you are certain that you are using purely line-out, then you can try this, but it would probably be better to simply turn it up until your mids and highs begin to clip, and use that as your volume on your test tone.

Adam, since you have 4 or so blue tops how did you know how many amps you needed? My batteries are brand new interstate deep cycle marine amps. By new I mean last Saturday new! No issues with them running down or going low because I checked them with a volt meter. I guess I wasn't specific enough when I said 13 volts in my original post but the volt meter read just under 13 so I ruled it out as a dead or not charged battery.

Thanks Tony, went with the 1000/1 because I'm going to put a 10w6 under the driver's seat this winter when I have time to fab a box. Just looked at the link you sent. Great but where do I get one of those disc? Best buy should have one, right?

Do you really think I need three batteries?

Ken , you misunderstood, I haev two (6v) golf cart batteries, equivalent to the amp hours of approx 4 blue tops. From what you just wrote sounds like your batts. are fine. you never answered. Is your amp going into protection or powering off? I know you've tested the voltage at the batteries , but what is the voltage at the amp itself? Go from the batt to the amp and test every point you can to see if you have a bad/loose connection somewhere. Don't eb surprised if the sub is rattling a slightly loose wire just enough to cause it to go into protection or possible power down.

Ahh, that makes more sense then, man that boat's gonna pound!

Any local audio shop should have a good tester CD to use.

I just thought of something else....if all this was done by a top-notch shop, why don't you just take it in and make them fix it? They shouldn't charge you a cent. If you're just looking to learn, then kudos, but you paid for good work and it should definitely be backed up by good support IMO.


Going along with Adam's ?'s, is the amp cutting out with the motor running as well, or only when it's off?

Sorry, I didn't have time to read all the posts....so don't flame. Assuming your amp is not in protection mode, I would check the power turn on lead from the radio. Some decks don't have the juice to sustain three amplifiers at once. Your deck may have a weak ground which will hinder the turn-on wire voltage. Sometimes it is necessary to use a relay for the turn ons.

Just another angle....

Tony- I think you referring to me when you stated why a (1) W6 and 1000/1 ? I have a 2nd W6 already boxed but wanted to solve my battery situation before I added the extra boom-boom. I tried the gain advice from JL and matched the gains with the appro voltage they recommended but my system sounded like @ss afterwords. I just set the gains by the clip method and it sounds much better.

Original poster had the 13w6 with the 1k/1 as well...but that's interesting that their own method didn't work out well. How big was the difference in your gain settings from voltage to clip method? And with clip, were your gains set lower or higher than with voltage?

gains were much lower when I didnt us the test tone-voltage method ! I used a $30 Ratshack digital multimeter so I dont know if that had something to do with it. My gains are less then half now but where almost tapped out using the test tone method. Fluid has a good point. Im running 3 Slash amps daisy chained off the HU remote lead, almost 30 ft worth of 14 gauge. Probably have to look into that as well.

KG, go up abotu 10 or so posts to Craigs...try that. disconnecting the remote turn on wires of your other amps and see what happens.

Test the Remotes too.

Disconnect the remote line from the HU (Very important in this test -- otherwise you're linking your battery banks together through the head unit as your grounds are already connected together somewhere)

Jumper from Batt+ to the remote. This will add 12v to the remote line and turn the amplifier ON.

Repeat test.

why don't you take it back to the person who installed it? You said the were the best. I would think a quality installer would be able to figuer out the problem in no time

You have some wires crossed causing the amp to go into a safety mode..

KG, I figured that would be the case (using lower settings than the voltmeter stated)...in the tutorial, it's specific about making the gain level that matches your voltage output the starting point only, and to make sure you only adjust down to get good sound, as opposed to going above it, which would clip the amp. It assumes you will need to adjust, but the purpose of the test is to make sure you aren't sending the amp into clipping range...which is why I suggested the test to OP, to make sure he wasn't clipping his amp

I plan on taking it back to them next week just hate hooking up to it if it's something that I might be able to check/change without towing it 15 miles out of the way. I'll check the ground wire tomorrow and do the tests above I'll let you guys know what the problem was. See it did this in the shop but he attributed it to the battery being low from them doing all the tweaking.