Guest orionkc Posted June 2, 2007 Report Share Posted June 2, 2007 I got the new 20uf clarity caps in yesterday and after a long day I started my restoration project about 11:00 P.M. Got the first one completed and it sounds perfect. I also replaced the woofers with the ones I got from an auction. 1st speaker functions perfectly.The tweeter isn't working on the second speaker after replacing the cap,cleaning the pots, installing the woofer and sealing. I hooked it up and no highs...The woofer is working as it should. Pots are OK as they were working perfectly with the old Sprague Caps. I loosened the tweeter and put a small load on it and it works if I bypass the crossover and just put power directly to the tweeter. I don't get any sound if I put power to the pot (green) that goes to the tweeter. I thought I might have dislodged something but checked all connections and they are good. Anybody know what I could have done or what the fix might be for this problem?I did the 2nd speaker just like the 1st. I cut the wires to the cap, 1 blue and the other green. wired the cap with the blue and the green, soldered and capped with twist cap. What could be wrong?My kids have a track meet today and I will be back this afternoon. Maybe I will have a little clarity after a long, hot day in the sun...LOL Any advice would be appreciated.Thanks,Rick Link to comment Share on other sites More sharing options...
johnieo Posted June 2, 2007 Report Share Posted June 2, 2007 Rick:Consulting at a distance is not easy. Sometimes circumstances are not described in sufficient detail; if they were, there wouldn't be a problem! :-) A couple of suggestions. One possiblity is that you put the wire nut on before the solder hardened resulting in a cold solder joint. Why wire nuts? Another possiblity-- if you resoldered an enameled wire from the coil after cleaning the potentiometer, you may not have scraped the insulation from that wire before resoldering; it's less than a half-mil thick and sometimes transparent. Yet another is the possiblity that you unknowingly disturbed another connection in the tweeter circuit.When this happens to me I quit and make coffee!Cheers, Link to comment Share on other sites More sharing options...
Guest hilltroll67 Posted June 2, 2007 Report Share Posted June 2, 2007 Try bypassing the pot, maybe with an 8 ohm resistor in the bypass line. Or, if you have a multimeter/ohmmeter, see if the path from before the pot to the driver is open.What you do if the pot is indeed bad is another story.Bob Link to comment Share on other sites More sharing options...
soundminded Posted June 2, 2007 Report Share Posted June 2, 2007 Here's another possibility, the new capacitor is defective. Take another capacitor known to work, the old one will do fine, and jump it across the new capacitor. If the tweeter works, it's the new capacitor. If not, recheck all of your connections. Jump out the pot if necessary. Try connecting just the tweeter in series with the new capacitor directly to the amplifier output. Keep the volume low during your tests. Good luck. Link to comment Share on other sites More sharing options...
onplane Posted June 4, 2007 Report Share Posted June 4, 2007 I agree with Bob. Chances are the pot is adding too much resistance and is straving the tweeter for current.You have two options for pot by-pass:http://www.classicspeakerpages.net/dc/user_files/2302.jpghttp://www.classicspeakerpages.net/dc/user_files/2303.jpgThe 2nd option is exactly the same as setting the pot to it's max increase position 40 years ago.1st option will provide a modest 1 to 2 db boost.Let your ears be your guide.Regards,Jerry Link to comment Share on other sites More sharing options...
johnieo Posted June 5, 2007 Report Share Posted June 5, 2007 It is not prudent to recommend modifying the crossover, especially to someone new to loudspeaker restoration. This has been proposed many times and should not be repeated ad-infinitum to each new person asking for assistance. Please do not remove the potentiometer or fix it at maximum. If the potentiometer is dirty, it should be cleaned, and if so badly damaged that it is beyond repair, then a one can either replace it with a reconditioned potentiometer, or with an L-pad that has resistance added in parallel to mimic the response of a potentiometer. The object should be restoration, not DIY design. Link to comment Share on other sites More sharing options...
onplane Posted June 5, 2007 Report Share Posted June 5, 2007 >It is not prudent to recommend modifying the crossover,>especially to someone new to loudspeaker restoration. This>has been proposed many times and should not be repeated>ad-infinitum to each new person asking for assistance. Please>do not remove the potentiometer or fix it at maximum. If the>potentiometer is dirty, it should be cleaned, and if so badly>damaged that it is beyond repair, then a one can either>replace it with a reconditioned potentiometer, or with an>L-pad that has resistance added in parallel to mimic the>response of a potentiometer. The object should be>restoration, not DIY design.Sorry, John, I couldn't disagree with you more. Neither Bob nor I are proposing a new design. What we are proposing is getting the speaker working again so that it can be enjoyed.Indeed the 2nd definition for "restoration" is:the act of restoring something or someone to a satisfactory state see: http://www.google.com/search?hl=en&defl=en...nition&ct=titleI think we'd all agree that a working speaker system is a far, far more satisfactory state than a non-working system. In short, get your speaker working, Rick. You can always "fine tune" once that is achieved.Regards,Jerry Link to comment Share on other sites More sharing options...
RoyC Posted June 5, 2007 Report Share Posted June 5, 2007 Hi Jerry,Other than for diagnostic purposes, I wouldn't recommend by-passing or eliminating the 4x pots either. The 4x cone tweeter is very different from the original 3/4" AR dome tweeter we have discussed in the past. Further, it is functioning in a 2-way system, crossed over rather low, and consequently covers a large portion of the 4x's output. My experience is that, depending on the room, it has a tendency to become harsh at even moderate volume levels. In my opinion the flexibility provided by the level controls is therefore necessary...I am very interested to find out what is actually wrong with Rick's speaker. Roy Link to comment Share on other sites More sharing options...
charger3834 Posted June 5, 2007 Report Share Posted June 5, 2007 I think there may be an important distinction between working and working properly, or as it was originally designed. The system was designed to have an adjustable spectral balance. Moreover, as Roy said, the AR-4x system typically operates with a somewhat retarded tweeter output due to crossover frequency that facilitates its inherently wide dispersion design. Link to comment Share on other sites More sharing options...
Guest Bret Posted June 6, 2007 Report Share Posted June 6, 2007 >I think we'd all agree that a working speaker system is a far, far more satisfactory state than a non-working system.<You must not have been in a Best City or CircuitBuy in a while. Bret Link to comment Share on other sites More sharing options...
Guest Bret Posted June 6, 2007 Report Share Posted June 6, 2007 Jerry,I think you miss the point of John's (and others') replies to you. Down in the Mods and Tweaks section would be a GREAT place for this information to go. . .There is a reason that the AR-3a, the AR-10pi, the AR-2ax, the AR- _____ still have a following while other, reputable, high-end-ish, speakers of high-quality manufacture of the same era are gone, ka-put, obsolete, not worth the time and money to fix, useless boat-anchors, abandoned, anathema, and without a following. The solution you propose brings the ARs more in-line with the sound and spectral balance of those abandoned designs rather than preserving that which makes the AR worth the time and trouble.Just as you cannot make a JBL sound like an AR by turning the tweeters down, you cannot make the AR sound "better" by turning the tweeters up. What you can do is make the AR sound like "something else" by permanently wiring the tweeter into a spectral imbalance that the designer would have avoided on-purpose.The title "better" almost always goes to the brighter design in an A/B comparison even though brighter is not truly always objectively, or even subjectively, better. Once your solution is applied it is more likely that the speakers, failing to give long-term satisfaction, will be trashed than it is they are likely to be un-mod-ed. Better to handle the problem than to create another problem. Link to comment Share on other sites More sharing options...
draftingmonkey Posted June 6, 2007 Report Share Posted June 6, 2007 Rick, Were you were able to fix the problem? Posts 1, 2 and 3 had some good information on what to look for. As you see we have some very passionate people here that sometimes get a little off topic in their replies, but they do mean well. Let us know how things worked out as we are interested in your results. Link to comment Share on other sites More sharing options...
Guest orionkc Posted June 6, 2007 Report Share Posted June 6, 2007 I checked the connections again where I soldered one side of the new cap to the common (blue)which connects to the red and goes to terminal 2 and to the terminal on the pot that goes to the tweeter (green) and didn't like the way the solder looked so I re cut and re soldered those connections. No sound from the tweeter. I thought for sure that would solve the problem. Still have sound from the tweeter when I bypass the crossover and put low power to the tweeter directly. When I try to apply power to the common to terminal 2 and the geen on the pot I get nothing either. Keep in mind that this was a fully functional speaker before I started. The pots were working too. I probably should have left them alone. They sounded good with the old caps but after recapping my ar3's I was anxious to do the same thing to the ar4x's. Link to comment Share on other sites More sharing options...
Guest matty g Posted June 6, 2007 Report Share Posted June 6, 2007 Hi Rick - It sounds to me like you lost the wiper or a winding on your pot. This is not uncommon - I had the same problem with both of my 3a's. On one of them the wiper completely fell off inside the pot and was causing trouble by rattling around in there and touching the wrong contacts. You might try temporarily removing the pot from the network just to assure that all other connections are ok, and then move on from there. I would not recommend removing the pot from the crossover circuit for any reason other than troubleshooting, however. Hope this helps!Matt Link to comment Share on other sites More sharing options...
RoyC Posted June 7, 2007 Report Share Posted June 7, 2007 Rick, I agree with Matt...the pot wiper really is the most likely culprit. Before pulling and dismantling the pot, send a signal to the speaker and simply touch a piece of wire between pot terminals "1" and "B". If you get no sound from the tweeter, then it is a solder joint or the cap. If the tweeter produces sound, you will need to take the pot apart to see what is wrong.Roy Link to comment Share on other sites More sharing options...
Guest orionkc Posted June 7, 2007 Report Share Posted June 7, 2007 You guys aren't gonna believe this. Checked everything and wasn't getting sound out of the tweeter after all. Replaced the tweeter and all is well. 4X's are singing and they sound fantastic. The older style cross hatched woofers that I installed are awsome. Can't believe the quality of sound coming from such a small footprint. Don't believe they can keep up with the AR3's but with the new 20uf clarity caps they are putting out some serious sound. I appreciate all the helpful tips and advice you guys gave me. The pots are perfect and function as they should so I now have a pair of fully functional AR4X's. I am really pleased with the results.Best regards and Godspeed....Rick Link to comment Share on other sites More sharing options...
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