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viking
08-07-2010, 02:47 PM
Ok you audio experts (ie..........dave, phil, brian). I am running 2 of these amps for my system. 1 runs the bow speakers and towers (new bullethollowpoints - awesome by the way and a big "shoutout" to Dave at Earmark). The other running the 4 cockpits and Sub. All details listed in my signature.

Anyway - was out pounding the system yesterday and enjoying the tunes. After a while of sitting and enjoying the music (at times pretty loud), I started the boat and when underway noticed that the cockpits and sub quite working. I checked the amp and the LED was blinking green/red. I read the manual and sounds like the amp went into protect mode. I'm assuming it was because of low voltage from the batts or something but then wouldn't both amps go into protect mode?? Why just the one?

I ended up shutting the stereo main breaker off at the dash and waiting about 5 minutes.........turned the system back on and all good.

Is this normal or do I need to be worried?

Brianinpdx
08-08-2010, 06:49 PM
Viking

I think Mandley is right on the money here about what happend. Quick suggestion is contact earmark (assuming you got the amps from them) and have him walk thru trouble shooting).

Like I always preach.. There is no magic, just physics. It's great that your amplifier was able to engage it's protection circuit and shut things down. If it didn't it would have destroyed itself.

So, should you be worried? No, not at all. Think it's time to look at a fan or two in the cubby and get some venting happening.

If you need more help, shoot me a pm

Brian
Exile audio

EarmarkMarine
08-09-2010, 11:42 AM
There are countless reasons why only one of two identical amplifiers would go into protection. Connections. Tuning(crossovers,EQ,etc). Low frequencies
drawing down the terminal voltage to a greater degree. Subwoofer with an inordinately low impedance or its voice coil has incurred some thermal damage. For starters you can redistribute the load more evenly by placing the most demanding draw (sub) with the least demanding draw (single pair of bow coaxials).

David
Earmark Marine

viking
08-09-2010, 02:35 PM
Thanks ALL -
maybe I was just taxing the system too hard? I figured with the Class D amps and second dedicated battery that I should be able to anchor and jam the system for at least a few hours? It's not often that I float and keep it that loud the whole time but there are going to be every now and then.

I'll keep you posted on my findings!

EarmarkMarine
08-09-2010, 02:44 PM
Viking,
Also keep in mind that this particular amplifier is strictly regulated so it works a little harder to maintain the same output level as the voltage supply declines.

David
Earmark Marine

viking
08-19-2010, 12:36 PM
OK -
So I think the culprit is it's just getting too hot. Was out again tuesday and 95degree day. Played the stereo all afternoon and didn't pound it at all. Just did a few pulls and some coving and same issue (the lower mounted amp went into protect) after about 3 hours.

Opened the cubby and it's warm as hell as you can imagine and the amps were hot to the touch.

What are the best solutions to provide some venting and/or air in the cubby?
I thought about possibly adding a fan of some sort in there wired to an accessory switch on the dash?

EarmarkMarine
08-19-2010, 01:34 PM
Viking,
Anytime you add a fan its many more times effective if you use it on a shroud so that the fan is circulating air over the entire heatsink rather than just around the fan.
A fan can be automatically turned on/off by the same relay that operates the amplifier remote turn-on circuit. Or, you can add a manual switch at the helm. Or, you can add an adjustable thermister for auto operation.
If you are wanting a fresh exchange in the locker then use a molded louvered vent in the pass-thru (in white or black to best match your gelcoat). To the interior of the vent you will use an ABS adapter plate to facilitate the fan. You will not need a second intake vent because there will be plenty of flow through the open gunnel cavity. Btw, we have these parts prefabricated.
A fan is a band-aid on a core heat issue that may still need to be addressed (redistribution of load, etc). I don't like the fact that the amplifier is generating that much heat to begin with, especially from a fullrange Class D, an issue that we don't see with that amplifier. But, its nice to see the circuit doing its job by protecting the amplifier.

David
Earmark Marine

viking
08-19-2010, 06:45 PM
Thanks David.
Can you email me the price and possibly picture of the louvered vent?
I might also discuss why it's working so hard with you as well and possible solutions other than fan/venting.

teamviking00@hotmail.com

cab13367
08-20-2010, 10:54 AM
How do u recharge the batteries after a day on the water? Or do you?

viking
08-20-2010, 04:13 PM
How do u recharge the batteries after a day on the water? Or do you?

Sometimes I do - sometimes I don't.

When I do, I just hook a battery charger to one of them and let them charge. I will alternate between which battery I hook the charger too. The charger will automatically go into trickle mode when they are full. I talked to Blue Seas about isolating them to charge each individually and they advised that it's the ACR's job to sense the charge and go to work so no real need to change it. Been good so far!

cab13367
08-21-2010, 11:16 AM
Sometimes I do - sometimes I don't.

When I do, I just hook a battery charger to one of them and let them charge. I will alternate between which battery I hook the charger too. The charger will automatically go into trickle mode when they are full. I talked to Blue Seas about isolating them to charge each individually and they advised that it's the ACR's job to sense the charge and go to work so no real need to change it. Been good so far!

viking,

Considering that you do a lot of coving and play your stereo with the engine off for hours at a time, you should probably be putting the charger on after each use. Once you play the stereo for a few hours then fire up the boat, the alternator does not provide enough output for a long enough period of time to fully charge your stereo battery. I had this happen to me and my amp went into low voltage protect. So I started researching battery charging and learned that you need a certain amount of current to correctly recharge and desulfate your batteries so I installed a ProMariner 20 amp dual bank charger and plug it in after each use. It can automatically send up to the full 20 amps to the battery that needs it so my stereo battery always gets fully reconditioned after each use.

You are right, the ACR will automatically detect the charger and will send the charging current to both batteries (i.e., it connects the batteries together) equally.

Al

EarmarkMarine
08-21-2010, 12:45 PM
An ACR has only one sensing mode. It combines or separates based on voltage. Obviously once you have a degree of charge the ACR combines the two batteries into a single bank thereby circumventing the isolation of a dual-bank charger. The charger is not able to profile and condition each battery individually so you lose an important and primary function of a smart charger.
The two batteries, starting and stereo, are used very differently and therefore age very differently and therefore present a different impedance. This practice shortens battery lifespan and eventually shows up as challenged voltage and reserves. Keep in mind that these ACRs and VCRs were designed for fishing boats with instrumentation (fishfinders, chartplotters, gps, etc) and did not anticipate the type of serious usage associated with large stereos. The manufacturers of these products naturally defend them. However, when I've interviewed their technical assistance personnel and dug a little deeper they could not answer key questions.

David
Earmark Marine

viking
09-06-2010, 01:17 PM
So after much pondering and many conversations with David at EARMARK (big shout out) I built an amp rack with cooling fans. Only other step I'm going to take is to install a vent van to blow air out the storage compartment into the walk through. Haven't done that yet. Took the boat out friday and pounded the stereo almost all day before having to let them cool for a bit :cool:

I would definitely buy all my gear from David in the future. He's been more than helpfull on several occasions with me and I wish his business was closer to me as I would just tow my boat over to him and let him have at her :) He goes above and beyond most. It goes appreciated for sure. Thanks again David!