OT: Vintage Loudspeaker Refurbishment

[TimD]

Originally Posted by dgauthier

There's no DC in a crossover circuit, so unlike a power supply the caps don't hold a charge...

Not to say that crossover capacitors are shock hazards, but...there may well be DC in the crossover if the power amp (section) has any significant DC voltage offset, OR if an op amp in your preamp fails in a way which connects the IC voltage rail to the output AND said preamp is DC-coupled (including, but not limited to, having a "LAB" output) AND that DC-coupled output is, in fact, the one connected to the amp driving the speakers.

See also Adcom. Interesting to see the woofer cones protrude, or retract, and stay there.

Ask me how I know this.

Tim

[Peter P.]

Originally Posted by Ken Robb

I understand no reading=blown speaker/open voice coil but how does a low reading=bad driver?

A low resistance would indicate a shorted voice coil. I might expect it to blow the amp or just overheat and melt the voicecoil.

I'd be curious what Oliver chooses to do.

Which makes me wonder if Oliver's speakers have fuses. Many speakers of that vintage did, internally or externally.

I wouldn't dissuade Oliver from taking this project on by dissing his speakers. He will certainly take pride in the result, and sometimes that's worth the expense.

Sounds like he wants to save money too, but I'll bet even after he re-foams the surrounds he'll be over his $100 budget. Maybe he should consider selling one of his bikes to fund a new pair of speakers.

Did I just say that?!

[dgauthier]

Originally Posted by TimD

Not to say that crossover capacitors are shock hazards, but...there may well be DC in the crossover if the power amp (section) has any significant DC voltage offset, OR if an op amp in your preamp fails in a way which connects the IC voltage rail to the output AND said preamp is DC-coupled (including, but not limited to, having a "LAB" output) AND that DC-coupled output is, in fact, the one connected to the amp driving the speakers.

See also Adcom. Interesting to see the woofer cones protrude, or retract, and stay there.

Ask me how I know this.

Tim

What shocking news! Thank you for correcting me.

[Web1111a]

Originally Posted by C40_guy

Listen to Bob. He (and I) sold audio equipment (true prosumer hifi) when these speakers were sold. They weren't good then. They haven't gotten better with age and degradation.

As someone whom also in the industry those are not worth the time

[Louis]

It sounds like the OP is most interested in the enclosures themselves.

Is there a cost-effective DIY solution where one guts the speakers and inserts decent modern parts producing sound that a non-super picky audiophile could live with?

[elvisthehorse]

check out GR research. He has a YouTube channel. They do amazing things with speakers.

[Bob Ross]

Originally Posted by Louis

It sounds like the OP is most interested in the enclosures themselves.

Is there a cost-effective DIY solution where one guts the speakers and inserts decent modern parts producing sound that a non-super picky audiophile could live with?

All new baffles w/ cutouts for (only) one modern woofer & tweeter each, plus new crossover...sure, could be an improvement.

[Ken Robb]

He could probably make it easy by installing a new 12" co-axial speaker and removing the other speakers and blocking the holes with 3/4" plywood. He might even find a buyer for any of the old speakers that still work.

[benb]

A well done home made resto-mod here to retain nostalgic value while making it sound better than new to me seems much cooler than just trashing it all and buying something completely new.

[oliver1850]

I would be happy to get them back close to their original specs but am open to suggestions for updates/improvements.

I will do something with them, they are not going to a bonfire or landfill.

I am decades past the ability to discern the differences between speakers as long as they don't melt down. I probably couldn't have heard the difference between an audiophile quality speaker and those of this quality in the 1970s. From the original specs, these seem to have been capable of playing loud, even if not for "critical" listening. Just capable of blasting Ramones, Guided by Voices, Zappa, BOC is all I'm looking for.

[C40_guy]

Originally Posted by oliver1850

I would be happy to get them back close to their original specs but am open to suggestions for updates/improvements.

I will do something with them, they are not going to a bonfire or landfill.

Hmm...

[Ken Robb]

[QUOTE=oliver1850;3367561]I would be happy to get them back close to their original specs but am open to suggestions for updates/improvements.

I will do something with them, they are not going to a bonfire or landfill.

I am decades past the ability to discern the differences between speakers as long as they don't melt down. I probably couldn't have heard the difference between an audiophile quality speaker and those of this quality in the 1970s.

My "Golden Ears" have turned to tin but I still hate distortion so I would put a 12" coax from someone like Electrovoice in place of your 12" woofers and remove and block the holes where the mid-range and tweeters reside. You might find buyers for them because other folks with blown speakers want replacements.

[Gsinill]

You also could reach out to Steve Deckert at Decware (www.decware.com) in Peoria.
He started doing exactly this before getting into the amp building business.
All around nice guy...

[Spoker]

Don't feel bad about the Walnut, I got staples cut in the backyard you can have for free.
Buy new modern speakers as suggested.

[William]

Originally Posted by Ozz

Didn't William rebuild some speakers a couple of years ago? He might have some good info....

I replaced the deteriorated foam surrounds and the capacitors in the crossovers on a pair a while back. Definitely a positive improvement.

You aren’t going to find any quality speakers for a $100 or under on CL or OfferUp unless you get lucky. The market has seemed to soften a little in the last month or so but vintage/quality audio equipment isn’t cheap like it was a few years ago.

Restoring those speakers is fine for nostalgic reasons. Otherwise if you really like the walnut cabs you could always DYI them with some modern drivers and crossovers or quality vintage drivers. You could always Econowave them as well.






W.