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Fried my speakers with a sweep tone, doh

Dzamija

New Member
So I was doing some testing and accidentally played a short sweep tone, very loudly, through my active studio monitors :banghead:. They were turned up really loud so it was kind of ear piercing and I could hear some distortion, and then the speakers shut themselves off and I haven't been able to turn them back on. The little LED that's supposed to light up when they're on won't light up, and there's no sound.

Based on this (very limited) information, do you guys think that they can be repaired, or that they're done for? I found some information online that tweeters can easily be fried using a sweep tone, but based on the symptoms this doesn't seem to be the case - the speakers just won't turn on at all, it looks more like some kind of fuse or protective element got blown out instead of the speakers and that they just can't be turned on now. The thing is that they turned off very neatly, basically like I turned them off myself, quite frankly it sounded like I accidentally unplugged them with my foot or something (I didn't).

Any ideas? I'll definitely take them into the shop first thing, but since you guys were very helpful and knowledgeable in the last thread I posted, I thought I'd ask for your opinion :)

UPDATE: Alright, so I tested out my satellite speaker (the one without the amp), and it doesn't seem to be blown out. I connected the leads using some alligator clips to my guitar (through a guitar pedal which is boosting the signal) and I can definitely hear it in the speaker. Extremely low volume, but I assume that this is because it's only getting 9 volts instead of the usual 120 which the speaker's amplifier provides. From what I can hear at this level, it seems to work fine, so the fuse is definitely the main suspect.
 
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rjenkinsgb

Well-Known Member
Most Helpful Member
Have you tried completely disconnecting them from power (at the wall) and waiting a few minutes?
Some protection systems only reset once power has been shut off; there is a chance they are OK, if they have such a system.
 

Dzamija

New Member
Have you tried completely disconnecting them from power (at the wall) and waiting a few minutes?
Some protection systems only reset once power has been shut off; there is a chance they are OK, if they have such a system.
Yeah I have, no luck, they definitely won't turn on :/
 

unclejed613

Well-Known Member
Most Helpful Member
most pro-audio equipment has fuse holders on the outside, usually next to where the power cord enters the chassis. they may also have them integrated into the IEC jack where the power cable plugs into the chassis.
090-443_HR_0.jpg
 

Dzamija

New Member
'Fraid I don't have this sort of neat compartment, there's just a backplate and a powercable coming out of it, it's not IEC at all (they're a bit cheaper, think I paid around $300 for them).

Anyway, I went into the shop and asked how much this sort of repair would cost, they said anywhere between $50 and $80. Even at $50 I'm thinking this is a ripoff if it's just a damn fuse, am I right or does this sort of fix really cost this much?
 

Nigel Goodwin

Super Moderator
Most Helpful Member
'Fraid I don't have this sort of neat compartment, there's just a backplate and a powercable coming out of it, it's not IEC at all (they're a bit cheaper, think I paid around $300 for them).

Anyway, I went into the shop and asked how much this sort of repair would cost, they said anywhere between $50 and $80. Even at $50 I'm thinking this is a ripoff if it's just a damn fuse, am I right or does this sort of fix really cost this much?
If it's just a fuse, then change it yourself - try checking what plumbers charge! - why shouldn't a much more skilled electronics technician charge similar fees (if not more?).

However, it's a bit optimistic that it might 'just be a fuse' - it also makes it a bit trickier as they are active speakers - you may well have the amplifiers in them (which at $50-80 would really be much too cheap).
 

rjenkinsgb

Well-Known Member
Most Helpful Member
What make and model are they? It's just possible there may be a service manual or schematic available, though it's a slim chance.
 

unclejed613

Well-Known Member
Most Helpful Member
Anyway, I went into the shop and asked how much this sort of repair would cost, they said anywhere between $50 and $80. Even at $50 I'm thinking this is a ripoff if it's just a damn fuse, am I right or does this sort of fix really cost this much?
it takes time to get the unit apart, find the fuse, replace it, and check the amplifier to make sure nothing else is wrong (like shorted output devices, etc...) and then test it if that's all it was. for a repair shop, $50 is basically for the tech's time plus shop expenses (electricity, storefront rental, etc...) for about an hour's worth of work. actually $50 sounds a bit cheap these days... when i had my CRT monitor repair business back in the 1990s, i charged $65/hr and i did a pretty brisk business...
 

Dzamija

New Member
it takes time to get the unit apart, find the fuse, replace it, and check the amplifier to make sure nothing else is wrong (like shorted output devices, etc...) and then test it if that's all it was. for a repair shop, $50 is basically for the tech's time plus shop expenses (electricity, storefront rental, etc...) for about an hour's worth of work. actually $50 sounds a bit cheap these days... when i had my CRT monitor repair business back in the 1990s, i charged $65/hr and i did a pretty brisk business...
Thing is, I'm not from the US, I'm from Serbia and the standard of living is generally much lower, stuff is cheaper, paychecks are lower ($550 is the average salary), so of course the hourly rate is going to be lower as well. I honestly don't know a single repairman who charges more than $8 an hour, that's just the way things are here. Just so you guys know I'm not a cheaposaurus, I'm absolutely prepared to pay the hourly rate as much as it costs, I just don't want to replace a transformer if it's fine, and the fuse is blown, that's just not worth $50 considering the standard. $20 at most.

Anyway, I reached out to Fluid Audio and a very helpful support agent told me that he'd send me the schematic on Monday and that as far as he remembers, there *is* a fuse, it's just on the inside, on the powercable (which looks like this):



So yeah, if I get the schematic I might just replace the fuse myself and go from there. :)
 

gophert

Well-Known Member
Most Helpful Member

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