Sound of a Speaker Going Bad?

[Kbibs]

Hi All,
I was playing my all original (except for recent cap job) '72 SF Twin with Utah speakers when I started to notice a crackling/rattling sounding type of breakup when I played certain notes or combination of notes. At first I thought it was a mechanical rattle of some sort but I think it got too loud for that, almost like it was being amplified. Is this the sound of one of the speakers going bad? ... I don't have any others to try so is there a simple way to answer this question? That is, is it just a matter of me popping off the grille and checking for tears or dry rot in the speaker cone? or is there more to it than that?

Next question would be, if it turns out to be a speaker what do I do? ... I could just pull the original Utah speakers and save them for resale value and put in replacements. ... Suggestions on replacements? I like a nice clear but warm sound, not too trebly.

Or I could have the originals reconed. ... Again suggestions on where to have this done?

Thanks!

[Dacious]

Cap job as in filters, or all electros? Sometimes it can be the small bias resistors on the board for the preamps, but if you are hearing metallicy overtones I would plump for the 25/25 bypass caps, about 7 of them in a typical reverb/trem Fender. This can also be caused by a bad solder joint. Even after 30 years they can crystallise and go bad.

When either goes, they allow odd frequencies to permeate.

[Kbibs]

Thanks for the reply Dacious.

I feel like an idiot! ... You know how the SFTR have the metal tiltback legs on the side and you know how they have the metal corner protectors on the cabinet. You guessed it! the two were vibrating against each other and the louder I played the more they vibrated. The notes I was playing at the time must of been at the right resonant frequency for the two to get excited!

BTW, I had all the electros replaced and I popped the grille cover off and the speakers still seem to be in good shape, i.e. no tears and the cones move freely.

Thanks Again!

[mad dog]

The last times I heard that sound it was:

-- cracked capacitor in a twilighter (magnatone) 260
-- separated speaker wire inside a weber 12A125 speaker in a Clark Tyger. Speaker didn't blow, fine now, but sure sounded like it blew.

The first time I blew a speaker was pretty impressive. BFDR, stock oxford, playing along in my living room and all of a sudden it sounded so freaking good, sound got HUGE and damn that was exciting for about 15 seconds before it blew. Best 15 seconds I ever got out of that amp.

[tele_jas]

Check www.tedweber.com (of weber speakers) and see if he can re-cone that speaker (if it actually needs it). He re-coned a non-weber speaker for me a couple years ago and did a GREAT job, for a pretty decent price too.

some signs of a blown speaker are as you described along with, no low end, nothing but fuzz out of that speaker, distorts very easy (very low volume), no tone at all......

You can replace it with another speaker, just keep the ohm and wiring configuration the same. A new speaker will sound a feel a bit stiffer and steril at first, but after it breaks in it'll sound much warmer and smoother.