Speaker wires shorted!

[colinB]

Just had some work done in my work place so had to dissmantle the sound system i had installed. I didnt notice the bare wires on the back of one speaker had come lose and had shorted. Does that normally blow a channel on the amp or have i burned out the voice coils on the speakers?

[Reid Malenfant]

The speaker will be 100% fine, I'd expect the amplifier will as well as most have short circuit protection. If they don't have that then they generally have a fuse on the output or on the amp power rails.

I can only think of one or two amplifiers that may well die given a short on the output ;)

[shabby64]

Swap the speaker cables round on the amp to find out?

[hifi_dave]

As Mark said - the speaker will be OK and probably, so will the amp but it depends on the design. I have only had damage occur to two amps over the years by s/cct and they were Michell Alecto and an old Exposure. Most are protected.

[DSJR]

One reason why I like the 1990's Audiolab and Myryad amps is because if the outputs are shorted, all you get is a loud click from the amp as the output stage is shut down (don't remember ever seeing a spark), which then attempts to re-connect after a few seconds. My ancient geriatric Crowns have localised VA limiting on each amp stage. so if a device fails, in the amp circuit at least, the damage is kept local and not passed on up the chain. Important for me, with the old irreparable speakers I use.

Am I right in suggesting that if the speaker wires are shorted at low or zero volume levels, you may get away with it for a few seconds at least? It's high power shorts that can cause fireworks I think.

[Reid Malenfant]

That'd depend on a few things Dave, the thickness of the loadspeaker cable for one, the amplifier output impedance for two, the DC offset for three.

Most amps will have current limiting though & close to DC this is generally at a lower current than at high voltage swings.

I stiill think his amp is likely to be fine. Probably best to stick a multimeter on the output though before reconnecting the loudspeaker - just to be sure :eyebrows:

[colinB]

Got a chance to swap the speker outputs and it looks like the speakers are fine but the Denon midi system has one channel gone. Have to get another one on from ebay and this time use banana plugs :doh:

[hifi_dave]

Have you checked if an internal fuse has blown ?

I have never had a problem with Denon amps. During demo's, I always turn the amp down when swopping speakers, never turn them off and I quite often touch the plugs together.

[Reid Malenfant]

I'm with Dave, Denon would not design an amp with no protection. Look for a blown fuse or possibly two inside ;)

[The Grand Wazoo]

Hi Colin,
Good to see you back - I hope all is well for you?

[colinB]

Both channels have come back ! Strange . Now i can carry on torturing the young staff with bbc6 music. Its my system so i get to play what i want he he.

Hi Dave, thanks feeling a bit better. No music in my house yet but catching the festive spirit and a wee bit more cheery :)

[Reid Malenfant]

Maybe it is strange, I'd have found it stranger if it had have popped though :eyebrows:


All good news :D

[shabby64]

Both channels have come back ! Strange .

Odd.....maybe it's got a thermal cut-out switch,similar to vacuum cleaners etc? :scratch:

[Reid Malenfant]

Odd.....maybe it's got a thermal cut-out switch,similar to vacuum cleaners etc? :scratch:
When you said that it made me think :eyebrows:

I reckon the amp is using more modern resettable fuses rather than types that will blow. These will reset but not straight away.

Good on you jogging my memory, though why I didn't think of this previously I have no idea :D

[Ali Tait]

It's senility Mark, comes to us all in the end. :lol:

[Reid Malenfant]

Quite possibly Ali :eyebrows: