lance G

Coincidentally I came across this on another forum yesterday. I cannot vouch for its validity or effectiveness, but it may be relevant to your issue/perceptions. "From Altec - 1974 The normal method to check speaker damping is simple, but is easiest if you start out with too little fiberglass. We recommend the battery test method to check for damping. Attach a short length of speaker wire to the loudspeaker terminals in the normal manner, and bring the loose end around front – where you can easily listen to the loudspeaker sound while testing. Hold one of the speaker leads to either end of a standard 1.5 volt flashlight battery. Then touch the second lead to the other end of the battery and release. A properly damped loudspeaker will reproduce a clean “click” as contact is made and released. The underdamped speaker will reproduce the battery contact as a “whomp” sound. Fiberglass may be added in a loose manner to the enclosure until the proper “click” is obtained, and then stapled into place according to above practices relating to the specific type of enclosure. The overdamped speaker is more difficult to observe. It is a matter of degrees that becomes familiar with one or two experiments. Thus, the recommendation to start tests with too little, build up, and then go back down as required." If you do try it perhaps let everyone know the outcome ? Thanks.

Well thank you !

And was it worth it ? What are your considered conclusions with the audible result ? How do they compare with other speakers that you have experienced/ are currently experiencing ?👍👎,🙂😲☹️. Thanks in anticipation !

Many thanks to you Giovanni, Attached picture is of one of my original crossovers before recapping all EXCEPT for the 2500 uF. Apparently mine are Callins as yours were, so seems like it's time to change them out ! Your information is really useful to me as I was given the impression, including from the forum, that it was acceptable to leave the 2500uF cap's in place as they are considered to be "historically robust".

Hi Giovanni. Most unlike you to not come back on this ?🙂. I (and likely others?) would be very interested in how far out the big cap's were ? Also which make (brand) they were ? Thanks in anticipation, Lance.

Particularly interested in this; "especially those in the 2500uF impedance compensation". Were they far out ? Many seem to say to not bother changing these, I suspect partly because of some difficulty in finding the correct value/s ? I am in the UK and may well have to resort to purchasing from the U.S. (Madisound or other ?) with the additional costs of doing so.

Result, and within 7 hours the OP has the answer ! To top it all it's one he wants to hear. Hats off to fedeleluigi !

So disappointed to see him downloading the latest music editing software on that old laptop. The day the music died.

How many got neither ?!!!

I can sense your excitement from here !

Check your wiring is correct against an accurate wiring diagram. The following may help, or after fully reading make things worse !!! https://community.classicspeakerpages.net/topic/16982-ar-90-first-time-listen-and-amplifier-pairing-question/page/2/

Maybe some new capacitors in the crossovers might be needed ?

Thanks, always good to have a definitive answer !

No stuffing ever installed from new, and not required ? This due to only very low frequencies and a requirement for large air volume movement in this area of the cabinet/s.

Not much help I know but it would be more of a sin if you could send indecent photo's ! Let's not discuss the rediculous size aspect !