Woofers Replacement

The impedance is easy enough to measure. There are so many different choices out there that I won't even begin to advise you. I'm certain that there will be many selfproclaimed loudspeaker experts who will extoll the virtues of their favorite speaker because of this or that characteristic.

Speakers can be re-coned, if that's why you are getting new ones, and you like these. That gets a new voice coil, too.

Loudspeaker performance is usually characterized by their Thiele-Small parameters.

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Speaker Analysis Using Thiele-Small Parameters

You can drive yourself crazy trying to select a speaker based on these properties, but lots of people get into that stuff. So much depends on the enclosure characteristics as that has a pronounced effect on loudspeaker performance.

You might want to characterize your enclosure using something like this:

Steve Ekblad's Free Audio Software and On-Line Enclosure Design

My advice is go buy something that is a quality product. KEF, Klipsch, JBL, and MANY other manufacturers produce quality products. Just depends on how much you want to pay.

Happy listening.

Some audio aficionados perodically take their woofers out, rotate them 180° and put them back. I understand the cones sag over time. I never tried it, but that's what I heard. Maybe you don't need new woofers.

When my Advents wore out, I got some JBLs. My NAD has twice blown its stereo output. Long I underpowered, but still stuff wore out. Now I'm old and don't care.

It has been a VERY long time since I worked in the audio field, but I'll share what I know..... or at least, what I KNEW!

Advent speakers tended to be of the 4 ohm variety, so yours may be 4 ohms also. However, if you measure them with a regular ohmmeter, you will get a reading which is surprisingly close to the impedance (assuming of course that the speakers are connected to the terminals in a reasonable manner, and not through 10 ohm inductors!)

Even though a speaker purist will frown on all this, you would be surprised how close you can get with an approximation from an ohm meter.

One thing, though: Advent typically would alter the mechanics of the woofer to get smoother response and a lower resonant frequency; in the old speakers made in the 1980's, for example, they "blew" a mixture of glue and what looked like shredded egg cartons (the heavy gray paper kind) onto the woofer. I always preferred those speakers to just about anything else anywhere near their price range! You should check your woofers to see if they look like they have been customized...

Sooner or later, every company seems to fall prey to putting cheaper off the shelf woofers in their systems, so check on the back of the magnets, on the frames, etc., to see if you can find a logo or brand name; if so, you can probably get identical replacements from a supplier.

Don't assume any of this is "expert" advice. Speakers are the one part of a sound system which is most subjective. One person may feel that a certain brand is terrific, while another may hate it because it is "harsh" or "mushy" or "stiff" and so on. If you can't find the exact replacements, get some good quality woofers and match them as best you can to your speakers. You'll be surprised how good they may work. If you tell the speaker supplier just what kind of bass sounds you prefer, they can probably match you up with some woofers that come pretty close.

This is almost off topic, but why do you need to replace them? If it is because the foam surrounds have failed, I have found it quite easy to replace those on my Advents (which are probably 35 years old and a different model from yours), and that is VERY inexpensive compared to replacing the speakers. Kits are available online, my purpose is not to promote any particular kit but I'm happy to share my positive experience with one kit manufacturer and to talk you through the process if you find you have questions after reading the kit instructions. As cheap as the kits are, there is little to lose in trying a kit on one speaker to see how it goes, if foam surround failure is the only known problem with the speakers.

sorry forgot to log in, that almost off topic post was from me.

The foam suspension ring deteriorates over time. This material is critical in keeping the spider/voice coil concentric with the magnet post. They are quite easy to replace and very inexpensive.

If the speakers are fused (and should be) I can't imagine any other reason for replacing them.

L.J.

Well, so far, no self proclaimed experts _{(except myself)} have appeared. Just well reasoned advice.

I saw somewhere the other day that someone was building cones out of hemp, and there were guys out there who swore by them. Soft sound, they said. Guitar players mostly. And you know how we are. It is mostly subjective.

Good luck.

Thanks all,

When I bought them through Craiglist I though, just like our Laughing Jaguar, why would then not work? The cone was intact and the fuse too, so I said: "sure, here is the cash". Mistake. They are ALL FOUR blown, I mean they fryed the coil so I cannot even measure the resistance. There is nothing written on them. And, just like some of you mentioned, it is not easy to navigate in an ocean of experts without much common sense.

BTW, when I was looking for those woofers I came across a turntable, the Goldmund Reference II that sells for 300 grants. I should call that company and ask what woofers should I use on my Advent....

They can be refurbished. It's done every day. Off the top of my head, $50.00 each to make them new.

They make DIY kits, too.

Good to know. I will perform the surgery so to reach the voice coil and find the interruption. I am a little intimidated by the basket under the cone: I hope some acetone will desolve the glue around it.

Everything you need.

Very interesting. So the only thing that stays original is the basket and the magnet, right? The coil on mine is on aluminum support, any input about that? I mean, do you think is important to have the same support?

You'll need something that fits your specific frame/magnet. This pic is generic.

The voice coil may be different. Round wire, square wire, aluminum support; check out some speaker forums. Audio forums maybe.

Before and after pictures are in order here. Get with it!

Good Luck.

It seems so weird to me that with all the progress done in all fields the loudspeaker remained basically the same. With the exception maybe of the electrostatic which I don't see too often around. Time to invent something totally new!

Thank you very much.

Consider that a bit of copper wire, a magnet and frame, and a paper cone can reproduce all that sound.

The inventor of the paper cone loudspeaker was Dr. Norman Hurd Ricker, PhD, and his accomplishment, though accidental, will never be surpassed. Improved upon, no doubt, but "surpassed" is unimaginable.

There has been much development in terms of materials and motor linearity though - I must agree - it is basically the same concept. I guess it is a bit like a motor car engine in this respect.

Google is your friend:

http://www.simplyspeakers.com/

http://www.oaktreeent.com/Advent_Speaker_Parts.htm

http://www.madisound.com/services/retrofits.php

I guess these guys can give you some direction. Also try asking around on a forum like AudioKarma.org http://www.audiokarma.org/forums/index.php

Good luck!

I decided that I will perform surgery on something else and let the people at Simplyspeakers do the reconing. Quantity discount for 4 woofers: $35 each.

Thank you all for your attention. And now I am going to work of a revolutionary type of speaker based on the interference of multiple resonating standing waves.

Just kiddng.

Good choice. While it's not especially difficult, I'd practice on a cheap "beater" speaker first.