Do blown speakers still provide the correct load?

[mrid]

I've been using by friends crappy Peavey cab for the past year or so, and I think it's about the bite the dust. At loud volumes the speakers fart and crackle, and I'm not sure I can hear one of the speakers working. Am I compromising my amp by plugging into this junker?

[BowerR64]

Re: Do blown speakers still provide the correct load?

Do you know how speakers work?

A few things can happen to a blown speaker. The coils can melt and short, or they can burn and break the circuit. Usualy when they get bad or start to get bad the epoxy around the coils will melt and expand causing the cone to drag this adds some crap to the sound.

The funny thing is some speakers are designed real weak so they breakup and get muddy this creates more distortion but its not the sound i like. I like a tight thick basket so the amp sounds the same at 1 or 10. I like the sound of my amp, i like the sound of my distortion but when its craked it dont sound the same with cheap 35 watt celestions.

My point is what kind of speaker is it? it could be breaking up from the natural design of the speaker.

Have you tried to measure the speaker with an ohm meter? You can also pop the speakers with a 9volt or a small low current supply. If it pops this tells you its not shorted out

[Kent S.]

Re: Do blown speakers still provide the correct load?

I've been using by friends crappy Peavey cab for the past year or so, and I think it's about the bite the dust. At loud volumes the speakers fart and crackle, and I'm not sure I can hear one of the speakers working. Am I compromising my amp by plugging into this junker?

Test the cab with your meter to answer the question, like the person before me stated, a lot of times speakers can get defromed from over excursion, coil can defrom and cause rubbing. The big no-no that can happen is that the coil can short ... more than likely it will go open though. For safety run the cab at lower volumes, if you're running it with more power than it wants then you could fry something, but again most of the time the coils will go open rather than short.

[ArtieToo]

Re: Do blown speakers still provide the correct load?

The insulation on speaker coil wire is just a thin shellac. While generally, a speaker will fail "open" and just quit, it is possible to have boiled some of the shellac off, causing the part of the coil to be shorted, or worse yet, to rub against the magnet during excursion.

Just to be safe, I wouldn't play it loud.

[mrid]

Re: Do blown speakers still provide the correct load?

Do you know how speakers work?

Yes, I read "The Way Things Work" when I was a kid.

This cab is rated @ 300 watts, which is 3 times what I'm putting into it. It's not the good kind of speaker distortion, I know what that is, it's the bad kind. If I have the volume around 5 and hit a note hard, I get a sound akin to plucking a bass string REAL HARD (ooowaaaahhh). It's very unpleasant to say the least...

[Kent S.]

Re: Do blown speakers still provide the correct load?

Yes, I read "The Way Things Work" when I was a kid.

This cab is rated @ 300 watts, which is 3 times what I'm putting into it. It's not the good kind of speaker distortion, I know what that is, it's the bad kind. If I have the volume around 5 and hit a note hard, I get a sound akin to plucking a bass string REAL HARD (ooowaaaahhh). It's very unpleasant to say the least...

Sounds like the coil could be deformed, or the suspension could be torn (along with the coil), the frame could even have been bent by someone upon installation ... it's really hard to tell ... heck the speaker mountings could be coming loose. If you can get to the speakers and can gently pump the cones in and out with your hand, and you feel rubbing, and you will if the cone, voice coil,windings are deformed then the gut needs to get them replaced. One thing of interest, and overdriven signal since it resembles a square wave a bit closer, also has the same attributes of a square wave ... meaning that the overall power seen by the load is more than what you think, a heavily distorted signal causes a lot of heat in the voice coil windings, and that heat can cause some problems ... it's really hard to say, but I'd be careful either way (you didn't say whether or not you were running distorted or not, but I thought I'd just throw that out there any way). A physical exam of the speakers... burns, tears, leads into coil, voice coil cap, the mountings, the surround, the hand pump/coil rub test, and checking the DCR on the coil (of each speaker individually) is about the only way to be sure, a sine wave sweep would be nice, but that's kind the owner's deal and not yours. Your amp probably has an output stage fuse, to be extra safe you might want to lower it's value so it would blow sooner (at least while using this particular cabinet). Just an idea, and turn it down some ... Let us know how it turns out, if a definite fault gets found.