AR-2 Tweeter Differences

[ninohernes]

These AR-2 tweeters (which are listed on ebay) have what appears to be fiberglass stuffed under the cones. The tweeters in my AR-2's do not have this. Due to the stuffing, the cones are somewhat "wrinkled", mine are not. Mabye the absence of the stuffing in mine is why I get such good high frequency extension compaired to some other AR-2's.

[ninohernes]

Here is the other pic. Aparently I can only attach one pic per post. Note the "wrinkled" cones.

[charger3834]

Joe,

Those AR-2 tweeters were built by Carbonneau Company and then modified by AR for use in the AR-2. AR then coated the surrounds with a damping compound. For further damping they placed the fiberglass under each cone. (I learned all that from Tom)

Perhaps early versions did not have the fiberglass. In some early versions, the two 5" cones are mounted in a aluminum housing as opposed to the cast-plastic ones that followed. (the plastic ones helped lower the AR-2 production cost)

[tysontom]

>These AR-2 tweeters (which are listed on ebay) have what

>appears to be fiberglass stuffed under the cones. The tweeters

>in my AR-2's do not have this. Due to the stuffing, the cones

>are somewhat "wrinkled", mine are not. Mabye the absence of

>the stuffing in mine is why I get such good high frequency

>extension compaired to some other AR-2's.

Joe,

All original 5-inch AR-2 tweeters, made by Carbonneau, were treated by Acoustic Research with fiberglass under the cone and coated with a butyl-rubber substance around the surround. This was done to smooth the frequency response and to improve transient response, somewhat at the expense of extended frequency response. AR felt it was much more important to have uniform, smooth response (even at the expense of extension) rather than simply have frequency extension to the highest octaves. This is also the reason the AR-3-type super tweeter was put in the AR-2a. The AR-2, incidentally, also had a crossover that equalized the response somewhat of the 5-inch tweeters.

If your 5-inch midrange units do not have the fiberglass under the cone and the treated surround, the drivers were retrofitted by someone with something else -- which may or may not be better than the original.

--Tom Tyson

[ninohernes]

These speakers are all original, and were never opened until I received them. My grandfather bought these new in 1960, and since around 1970 they have been in my fathers posession. In around 1994 they have been in my posession. I opened them for the first time in 2003 to install new level adjustments, and that was the first time that they had ever been opened. The serial number of one of the speakers is B 59704. I do however, have the coated surrounds, which are still tacky I might add.