AR-91s, Worth restoring?

[Guest monoural]

I have a set of ar91s, with non-oem woofers. I am pretty sure they are 8 ohm woofers, off brand. Anyways, the mids dome crackles when you crank it. I believe it to be something in the crossover. I have a Quadraflex 650FETr (65x2@4ohm) running to them. I do not plan to upgrade that anytime soon. I know very little about these speakers, except I got them for ten bucks, and I really like how they sound. I know my way around 12v sound, but home is a little different. Would something fail in the crossover if the wrong impendence woofer was used? Or perhaps a known trouble-spot in the crossover, or a part used in it? I don't wish to put more than 200 dollars into these things, mainly because the cabinets aren't in pristine condition (but they do look alright). Also, would a set of quadraflex ST-19s be a better place to start? I was impressed by those speakers as well, but there seemed to be a little strong in the midrange.

[Supercooper188]

Like most AR products the AR-91 was a great speaker, and the reason it sounds a little strong in the mid area could be due to the woofers not being original. The 12" woofer by AR produces a lot of bass and is one of their strong points.I am very particle to AR and I have listened to a lot of speakers, but for some reason with AR I never get the listener fatigue. Don't know if it is reality or if it's in my head.

[onplane]

>I have a set of ar91s, with non-oem woofers. I am pretty sure

>they are 8 ohm woofers, off brand. Anyways, the mids dome

>crackles when you crank it. I believe it to be something in

>the crossover. I have a Quadraflex 650FETr (65x2@4ohm) running

>to them.

monural:

The drivers in your AR91's are:

DRIVE UNITS One 300mm (12") acoustic suspension woofer. One 38mm liquid-cooled dome midrange driver with semi-horn. One 19mm liquid-cooled dome highrange driver.

The liquid-cooled drivers are able to handle power better than the earlier drivers that AR used. Nevertheless, it's possible that both are damaged, but the probabilities that both are shot? Next, what is the probability that a component in both xover networks is bad? Once again … pretty low!

AR’s are notorious for consuming vast amounts of power. monural, if you really want to “crank”, before you spend any $’s on new drivers, I’d borrow a huge amp and test again.

What you hear as “crackling” could very well be caused by an amp that is over taxed. There are decent amps that "choke" on the very low impedance of AR speakers.

POWER HANDLING ABILITY May be used with amplifiers capable of delivering up to 200 watts continuous power per channel, being driven into clipping no more than 10% of ihe time on normal speech and music source material in non-commercial applications.

IMPEDANCE 4 ohms nominal (3.2 ohms minimum)

As for the woofers, the AR woofers had a “flat” side on both sides (see pic below). If your woofers look like this, then they are probably original.

http://www.classicspeakerpages.net/dc/user_files/1673.gif

Hope this helps …

Jerry

[dingus]

yes, they are worth restoring. he's a shot of mine with original woofers (surrounds refoamed) along with a short review.

http://www.sound-thinking.org/index.php?showtopic=714

[nfmisso]

>.....I have a Quadraflex 650FETr (65x2@4ohm) running

As mentioned above, this is not adequate power to drive a pair of AR91 speakers, even in a tiny room.

AR used 1000W (one thousand watt) amplifiers in thier live versus AR comparisons, whiched used AR11 speakers, an older, but very close cousin of the AR91.