Members abzurd Posted September 16, 2014 Members Share Posted September 16, 2014 I actually thought this was good news as I thought the speaker was going. Turns out on certain songs the resonance of the box causes the sketchy connection to come and go. Jiggling the connector confirmed this. I was encouraged by the screws on the outside that it would be relatively easy to replace, but now I'm not so sure. The XLR jacks are soldered to the PCB. Notice in the picture that the jack on the left has only 1 solder while the other XLR has solder on all 3 connections. I'm wondering if this is by design or a gaff in production. I can jiggle the connector and get it to drop out, but I don't think I'm flexing the jack when I do it so as to make it break connection at the PCB. Thoughts? The forum doesn't let me know when I receive replies to anything so I may not be back timely. Thanks, Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 16, 2014 Members Share Posted September 16, 2014 Appears to be "by design" but the top trace may be paralleled by a bottom trace with solder pads.Resolder (carefully) all XLR connections. This is not good design practice BTW, but I have seen it before on boards with plated through holes. Normally, the pad stack is identical on top and bottom but if there is only a bottom pad, it can work just fine. Link to comment Share on other sites More sharing options...
Members abzurd Posted September 16, 2014 Author Members Share Posted September 16, 2014 It seems like the problem is in the connector pre PCB. The XLR connection works best when not clicked in, but rather inserted 1/2 way. Can I order an XLR like the one shown? Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 16, 2014 Members Share Posted September 16, 2014 Is it possible that a contact got bent from a Chinese XLR plug pin? Re tensioning of the contact bay be your beat bet Link to comment Share on other sites More sharing options...
Members abzurd Posted September 16, 2014 Author Members Share Posted September 16, 2014 Is it possible that a contact got bent from a Chinese XLR plug pin? Re tensioning of the contact bay be your beat bet I doubt it. All my XLR's are from Mark and I've never had a problem . It could be from using them as monitors and having them over tilted with an XLR resting on the floor. How would one "retension" a contact? Link to comment Share on other sites More sharing options...
Members Pro Sound Guy Posted September 17, 2014 Members Share Posted September 17, 2014 Honestly it sounds like a bad cracked or cold solder connect.Look at the solder connections to the PCB with and eye loop or some type of magnification.Get the old solder off and re solder it Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 17, 2014 Members Share Posted September 17, 2014 First, just resolder. Don't worry about removing the old solder. Flux in new solder plus just a little solder is fine. Try this first. Re tensioning contacts takes a tiny flat blade screwdriver or tool like object and a magnifying glass. It will be obvious once you look, depending on the style of contact. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted September 17, 2014 CMS Author Share Posted September 17, 2014 It's hard to see for sure, but that single solder joint on the left XLR sure looks cold in my pic. Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 17, 2014 Members Share Posted September 17, 2014 Hard to say, lead free solders don't look the same when they cool. Always a bit grainy looking. Link to comment Share on other sites More sharing options...
Members RoadRanger Posted September 17, 2014 Members Share Posted September 17, 2014 Hmm... I really have to open up my crackling 310A and see if that's the problem. Quite possibly . Link to comment Share on other sites More sharing options...
Members abzurd Posted September 18, 2014 Author Members Share Posted September 18, 2014 Hmm... I really have to open up my crackling 310A and see if that's the problem. Quite possibly . Before you open it, plug an xlr in and wiggle it to see if it maintains connection. The fact it's losing connection there makes me doubt it's a connection at the PCB. I'll probably contact RCF and see if they can assist. I gotta say, I've not been super happy with the reliability of my RCF stuff. Link to comment Share on other sites More sharing options...
Members Dookietwo Posted September 19, 2014 Members Share Posted September 19, 2014 In looking at the XLR on the left (the one with only 1 soldered pin) it looks like there is so much solder on it that it is touching more than one pcb trace. Hard to tell by the picture. Maybe its shorting to the other trace? In wave solder boards its odd to see a so/so solder job like that. Has it been repaired before or are these new? I'd get some solder wick and clean them up and do them over. Doug Link to comment Share on other sites More sharing options...
Members OneEng Posted September 19, 2014 Members Share Posted September 19, 2014 Appears to be "by design" but the top trace may be paralleled by a bottom trace with solder pads.Resolder (carefully) all XLR connections. This is not good design practice BTW' date=' but I have seen it before on boards with plated through holes. Normally, the pad stack is identical on top and bottom but if there is only a bottom pad, it can work just fine.[/quote'] Yep. That is what it looks like to me too. If it were not soldered, there would still be silver pads on top that you could see were intended to have solder on them. The easiest thing to try would be to reflow the solder on the top and bottom pads for that connector. By "reflow", I mean all you do is touch a soldering iron to it until the entire solder melts, hold it there for .... say 15 seconds, then remove the iron. I usually "wet" my soldering iron tip before I do this so that the heat is immediately transfered to the joint. "Wetting" the tip means to put a small amount of solder from a roll on your tip. It should adhere to the tip in molten form. Then you touch the bead to the joint. If that isn't the problem, then you need to remove the old socket and replace it. This is a little trickier than just reflowing. To do this you will want a solder sucker (perhaps there is a more scientific term for these, but this is what I call them), and/or "solder wick" Both are used for the same purpose .... to remove solder from an existing joint. I generally try to use the sucker first. I am decent at getting all the solder out this way. You will definately want to remove the board from the speaker to work on it. There is nothing more irritating to me that to have to do solder work (which I am not any good at anyway.... fortunately for me the boys in the lab are ) while constrained in a tight area where I can't get the iron where I need it. Once all the solder is gone, the socket should come out pretty easily (unless someone bent the tips over on the bottom of the board. Make sure to check this and if they did, straighten the leads out with a pair of needle nose pliers. The sockets can be purchased easily from a number of places. I buy my stuff from partsexpress.com. They have always had everything I needed and have a decent search engine. Digikey is good for general electrical parts. I recently did some repairs on my Digitech 2120 foot controller. I sent them an email asking for the part number for the switches and they gladly sent it to me. That made it easy for me to order the right part. It is possible that another part will work, but the fail-safe way is to use the part that OEM used. Remember, the speaker OEM doesn't make its own connectors. They get them from somewhere too. All you have to do is find out the part number and you are in business. Oh, and just a personal opinion ... while lead is a bad thing, leaded solder is SOOO much easier to work with IMHO Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 19, 2014 Members Share Posted September 19, 2014 You need to use a little fresh solder when reflowing, the flux contained in the core is essential to the reflow process. Even more so if the existing is lead free. Always use the identical factory style parts for anything electromechanical, otherwise things won't mount up. You can use the OEM part if available or from RCF is not available. Many times the OEM PC mount parts from electronics suppliers have really large minimums for obvious reasons. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted September 19, 2014 CMS Author Share Posted September 19, 2014 In looking at the XLR on the left (the one with only 1 soldered pin) it looks like there is so much solder on it that it is touching more than one pcb trace. Hard to tell by the picture. Maybe its shorting to the other trace? In wave solder boards its odd to see a so/so solder job like that. Has it been repaired before or are these new? I'd get some solder wick and clean them up and do them over. Doug Yeah, I was wondering if the solder blob was shorting intermittently too. Hard to see for sure in the pics. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted September 19, 2014 CMS Author Share Posted September 19, 2014 Hard to say' date=' lead free solders don't look the same when they cool. Always a bit grainy looking.[/quote'] Yep, but in my view the pic looked as if the pin was cold and didn't wet. Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 20, 2014 Members Share Posted September 20, 2014 Doesn't look like it to me. Link to comment Share on other sites More sharing options...
Members Pro Sound Guy Posted September 20, 2014 Members Share Posted September 20, 2014 Please ship the PCB to a central location we can all look at it together, otherwise its a crap shoot. Link to comment Share on other sites More sharing options...
Members abzurd Posted September 20, 2014 Author Members Share Posted September 20, 2014 Please ship the PCB to a central location we can all look at it together' date=' otherwise its a crap shoot. [/quote'] I'm in Ohio. Is that central enough? I don't think I'm qualified to bust out the soldering iron on this thing. I still think it's in the actual jack itself. I only removed the amp to see if I could remove it and put in another. That's when I discovered it wasn't going to be that easy. I can plug a cable in 1/2 way and not lock it in and it will work fine. It's when I lock it in that it can get goofy. The last few shows I've just pushed it in most of the way and put a piece of gaff tape to hold it in place. Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 20, 2014 Members Share Posted September 20, 2014 Sure sounds like a bent female socket contact. If the connector PCB comes out easily and you want to throw it in the mail to me, I can take a look, repair (if possible) it and send it back to you for the cost of the postage. Link to comment Share on other sites More sharing options...
Members abzurd Posted September 21, 2014 Author Members Share Posted September 21, 2014 Sure sounds like a bent female socket contact. If the connector PCB comes out easily and you want to throw it in the mail to me' date=' I can take a look, repair (if possible) it and send it back to you for the cost of the postage.[/quote'] Thanks Andy. Unfortunately it looks like mailing the whole amp is the only safe way to do it as it's essentially 1 PCB with everything but the transformer on it. I did take a pic of the other side of the PCB. It looks like all those solders are good. It's the triangle pattern and the straight pattern, with an extra solder under the center one. The other pic is the whole PCB. Link to comment Share on other sites More sharing options...
Members OneEng Posted September 21, 2014 Members Share Posted September 21, 2014 Thanks Andy. Unfortunately it looks like mailing the whole amp is the only safe way to do it as it's essentially 1 PCB with everything but the transformer on it. I did take a pic of the other side of the PCB. It looks like all those solders are good. It's the triangle pattern and the straight pattern, with an extra solder under the center one. The other pic is the whole PCB. It's too bad you aren't a little closer to the Detroit area. I would charge you my standard "1 beer" I reserve for friends and relatives I just got back from a weekend in Sandusky, but I think you are a bit farther south than that. Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 22, 2014 Members Share Posted September 22, 2014 I don't think it's the solder joints. Looks like the standard Neutric PC mount footprints. I am awfully familiar with them I also see what looks like my favorite HF amp IC in that package. Link to comment Share on other sites More sharing options...
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