212 sub is not fused

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GW1800

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Question about fusing a sub. The Descent i is a fused sub yet the newer 212 and I assume the 210 is not. Does anyone know why ML would do this? Had a brown out at a relatives place and his 212 is now dead. I think if it was fused could be an easy fix but now I fear a return to service.
 

ttocs

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Well, I never even thought about checking to see if our speakers and subs have fuses, which I thought they would have, but don't. All my amps have fuses, and the powered speakers and subs have amps, so, wouldn't they have fuses? I guess not.

With that said, my amps got hit with a electric utility event on a beautiful and calm night, where the power went off/on/off/on/off/on in less than two seconds. Like I said, all the amps have fuses, but they all suffered some damage, and the Krell got hit the worst - and it has the most fuses. The Krell has two fuses on each amp blade, and a bunch of fuses elsewhere, but only a couple fuses were blown - and continue to blow each time power is applied.

The point here is that fuses aren't a guarantee for less or no damage, but one would think there would be a fuse on the main power connection of a powered sub.
 

FruitloopSR

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Would a real good surge /spike unit help solve that. I am using Shunyata Triton V3 for system/ Audioquest for video
 

GW1800

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I get that fuses are not a total answer but they do serve a purpose and in many cases work as intended.

I have a whole power panel surge protection which I’m sure helps however not sure if it helps to protect for a brown out that happened at my son in laws. I’m checking with Square D but no response yet from them or ML so far to my Voicemail this morning.

However we have gotten off point here a bit as the original question is why did the previous generation of ML subs have a fuse but the new ones do not?

My son in law did get a response saying that the whole amp section needs to be replaced so apparently there is no internal fuse either. Ouch!! This is a predictable outcome with a none fused component. Also the odd thing his CLX’s, Stage X, Parasound A21+, Anthem 540 receiver and LG OLED did not have an issue only the single 212 which he has only the one.
Well, I never even thought about checking to see if our speakers and subs have fuses, which I thought they would have, but don't. All my amps have fuses, and the powered speakers and subs have amps, so, wouldn't they have fuses? I guess not.

With that said, my amps got hit with a electric utility event on a beautiful and calm night, where the power went off/on/off/on/off/on in less than two seconds. Like I said, all the amps have fuses, but they all suffered some damage, and the Krell got hit the worst - and it has the most fuses. The Krell has two fuses on each amp blade, and a bunch of fuses elsewhere, but only a couple fuses were blown - and continue to blow each time power is applied.

The point here is that fuses aren't a guarantee for less or no damage, but one would think there would be a fuse on the main power connection of a powered sub.
 

GW1800

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I appreciate the comments of fuses are not always the answer and some surge protection device that you plug your system into. However my question was why is this current sub not fused when it’s unit it replaced was. Seems like component 101 to fuse a device. I know some of my components have a circuit breaker instead that is supposed to be superior to a fuse but to totally eliminate any protection escapes me what possibly reason for removing it was a good idea.
 

ttocs

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However we have gotten off point here a bit as the original question is why did the previous generation of ML subs have a fuse but the new ones do not?

My son in law did get a response saying that the whole amp section needs to be replaced so apparently there is no internal fuse either. Ouch!! This is a predictable outcome with a none fused component. Also the odd thing his CLX’s, Stage X, Parasound A21+, Anthem 540 receiver and LG OLED did not have an issue only the single 212 which he has only the one.
I wonder if it's because all of these non-fused subs and speakers have Auto Sense power up? Maybe there's something in that circuitry which "acts" like a fuse ?

It'll be interesting to hear what you find out from ML.

Also the odd thing his CLX’s, Stage X, Parasound A21+, Anthem 540 receiver and LG OLED did not have an issue only the single 212 which he has only the one.
You would think a tv would be an easy target, but mine is fine also other than the fact that many settings reverted back to factory default, just as happened to several sources.

The ML speakers which have the voltage adapter, I suspect would offer some protection from voltage that's out of range, so it would either work or not work. But the subs and speakers with powered woofers have power cords which allow for full voltage and amperage, so the question is, is there something in the circuitry which clamps the current in a spike situation? I doubt there's much that can be done for under-volt/under-current condition.
 

Gordon Gray

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Absent explanation from ML as to why there is no fuse, seems like a major oversight and ML should be responsible for all repair costs.
 

Leporello

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Question about fusing a sub. The Descent i is a fused sub yet the newer 212 and I assume the 210 is not. Does anyone know why ML would do this? Had a brown out at a relatives place and his 212 is now dead. I think if it was fused could be an easy fix but now I fear a return to service.
I would have thought a fuse is a requirement for UL certification which would be required to be legally sold. You sure there is no fuse, like in a power entry module next to the power connector? Usually requires a small screwdriver to pull out the carrier. As other posters have said, a fuse is no guarantee against brownout conditions. I’m keen on upgrading my Descent i some day, but I’ll keep that in mind, that bad power conditions can fry a BF210.
 

GW1800

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Nope nothing. We removed the back panel of the 212 and the
Power goes straight into each amp nothing either external or internal to protect.
 

GW1800

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Service should call me back Monday to explain. I’m sure there is a good reason but still it’s got to be a whopper to eliminate protection. Like I said previously the top sub
 

Gordon Gray

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Curious as to how many powered subs are not fused. REL, SVS, JL Audio, Paradigm and Wilson Audio appear to be fuse protected.
 
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GW1800

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Gordon I’m not quite sure what you are saying are all the mfg you mention have fused subs?
 

Gordon Gray

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Based on my cursory research, yes. Did not look at all models. I hope that helps. Good luck.

Gordon
 
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GW1800

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I’m sure ML did what they did for a good reason.
 
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