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[Refuse Winst]

I was looking around online for some help with the problem I'm having, but couldn't find any info. Hopefully someone here can help out...

A few years back I bought a Fender M-80 160 watt bass head and an old Peavey cabinet. I don't know what the model number is (or if there even is one) of the cabinet, but it's an old cabinet with a rear-facing speaker. It's designed for an 18" speaker, but the person that sold it to me had replaced it with a 15".

At the time I bought the equipment, I wasn't playing with anyone, and it ended up sitting in a garage for a couple years. At the beginning of the year I started playing in a band again and got it out. Before long the head stopped working. I replaced it about 3 or 4 weeks ago with a brand new 700 watt Peavey tour series. Because of the design of the cabinet making it difficult to get at the actual speaker, I foolishly procrastinated checking the wattage of the speaker in the cabinet. I played with this setup for a few weeks without any problems.... that is, until tonight. At the beginning of our third song, my sound just dropped out. Nothing. I did the usual run-through of checking all the leads, pedals, etc. Nothing. At this point I was starting to think it was the new head... well, it's under warranty at least. But just to check I ran our PA to my cabinet to see if I got a signal from the speaker. I didn't.

I started pulling the cabinet apart to get to the speaker. As soon as I pulled off the panel to access the speaker, a puff of relatively thick smoke billowed out from where the speaker sits, and there was the distinctive smell that something had burned. I pulled the speaker itself out and inpected it, but it looked fine and I couldn't find any black or burned areas on the surface. I also check the input jack just to be sure and it looked fine. All connections checked out. It seems that the speaker itself had apparently burned out on the inside somewhere.

I'm going to buy a replacement speaker before our next practice, but I'm wondering if anyone can tell me what caused this, so I can avoid it happening again. When I got to the speaker, I saw that it was 4 ohms and 600 watts. My amp is 700 watts, the speaker output says 4 ohm minimum, and I had both pre- and post-gain just under 5 (halfway) when it burned up.

Any ideas or suggestions? I have to admit I don't know a whole lot about this kind of stuff, but I thought a speaker would just blow (or at worse cause damage to the amp) instead of the actual speaker burning out!

[Herb]

Sounds like you smoked the voice coil. Push the speaker cone up and down in the frame, if you hear scratchy noises, the voice coil's gone.
_________________
Yer guitar pickin' friend,
Herb
"It don't mean a thing if it ain't got that swing!"
Doghouse Jazz

[Refuse Winst]

Thanks for the reply. Unfortunately I don't have the speaker at my house (it's at our rehearsal space a half hour away), but I did order a new 18" 800 watt 8ohm Eminence speaker yesterday, so hopefully everything will be cool. I'm just hoping I didn't somehow damage the head in the process, though I believe that head has some kind of circuit to keep it from overloading. I guess I'll find out when I get the new speaker put in.

Thanks again for the help!

[nigelwright7557]