AR28 replacement woofer

[VictorG]

My dad has this old pair of AR28s, and i remember loving the sound when i was a kid. Unfortuntly he has not benn able to use them for 5+ years because the foam sourrounds on the woofers rotted away. So now I turn to the expertice and knowldge of this forum to recocmend a driver that might fill the job of the original woofers. It's looks like a 7 incher. Even if you arnt an expert on this particular type of speaker, I would still like reccomendations on speakers that could probobly foot the bill for this type of speaker. Not looking to spend a fortune (ex nay on the seas), just want to get em back in working order for my dad before x-mas. Thanks Guys.

[ironwoods]

Send 'em in, or DIY.

[sreten]

The only real way to go is to have the surrounds replaced.

The picture shows a pair with the surrounds replaced.

try :

http://www.speakerworks.net/kits.html

Getting a driver with the right sensitivity, specs, response etc is
almost impossible and a poor choice compared to the above.
more expensive too.


/sreten.

[VictorG]

problemo-
my dad threw them out when the surrounds went bad! Alternative?

Thnx,
Brian

[li_gangyi]

check ur old speaker repair centre...they might have a pair lying around...well my speaker repair centre does have a few...

[kelticwizard]

Here is a guy who is actually selling a pair at a reasonable pricel.
http://members.aol.com/KDresch/ar-28s.html

Can't vouch for the guy, just ran across it on the Classic speaker page, but that is it.

Many AR's including possibly this one, had an 8" woofer that rolled off naturally at 1800 Hz or so. Actually, for many years, AR 8 inchers all had the same woofer!

The clossic speaker pages had an article on AR 8 inch woofers that I am trying to dig up.

[VictorG]

so keltic-

you seem to know even a little about these woofers, if I needed to get just the woofers, and not ship a new set, what basic parameters would I look for (sensitivity, impedance ect.) I mean your educated guesses are more than i got, these speakers arn't even my era! Thanks, Brian

[kelticwizard]

What is the exact model of your AR-28? There were several.

Here is a page with about a million different links on it.
http://www.arsenal.net/speakers/ar/ar.htm

There is even an audio forum devoted to this, on the page, also accessible by www.arsenal.net

There is an article where the fellow goes through a long thing about a present replacement for the 8" woofer.

There was a thread I dealt with before, I believe the frequency response is on it.

I believe that 8" did not have an electrical crossover. It rolled off gradually by itself. To find a replacement, you would need an 8" that gradually rolled of at approximately the same place.

It is possible that you will find one. Might take a little time.

As I recall, the professional who sells *' woofer replacements charges about $50 for them, that is why I recommended getting the used set.

I would also follow li gangi's advice and check out local speaker repair centers. Because AR used pretty much the same woofer on most of it's 8" models for many years, a speaker repair center is likely to "pull" some out of speakers the owner did not want to repair, or traded in, or whatever. I think it is quite possible that you can get a deal on just the woofers locally.

If you want, I can check out some good *' woofer frequency response charts to see a similar rolloff. My guess is that the woofers, might be in the $50 range each. But I will do a quick check, if you like.

If these are the model I believe these are, the intrnal box volume is half a Ft³, or 14 liters. The boxes are 3 dB down at 50 Hz, according to AR literature-if it's the model I thought it was. A set of parameters for a replacement 8" would be:

Impedance=8 ohms
Fs=25 Hz
Vas=1.5Ft³ or 42 liters
Qts=.4 or thereabouts
Sensitivity, (commonly called efficiency)=87 dB or so

But there are other parameters that will work.

Be sure to let me know the exact model number. And check out a couple of electronic repair stores. I really do think the chances of getting one cheap are very good-so many different models and years using the same woofer....

[sreten]

try :

http://www.speakersupply.com/AR.htm

new AR drivers $55 each,
AR poly/rubber version $58 each (probably best long term),
pattern replacements $45 each.

KW is correct, the bass/ mid unit does not use a crossover, it
has a designed in mechanical roll-off to match the tweeter, very
difficult to find a modern unit designed to be used this way.


/sreten.

[kelticwizard]

Sreten:

Thanks for that link. That is precisely the page I had seen months ago and was searching to try to find.