Coytee Posted September 12, 2006 Share Posted September 12, 2006 Ok braintrust... I need some help & guidance before I'm made to be the fool on Saturday when I have some high profile Klipsch-0-phyles coming to my house from 4 hours away, to hear the Jubilees. Won't be cool when I turn it ON and hear buzzzzzzzzzzzzzzzzz. A very expensive buzzzz I might add!! ok, here's the scoop. I bought the little 2-way transformer that Doc/Who told me about. It's RCA in (main input) and has XLR output. Those went to my EV main inputs. Out of the four XLR outputs, two were REQUIRED to go to a XLR input which was fine. The McIntosh 2102 had XLR/RCA inputs. The other two XLR's went back into the SAME transformer box and had an RCA output on the front side. The downside of this was I'm stuck having one XLR amp and I dont necessarily want that. Also, it looks bad, more wires and it chewed up an empty socket. Here's what I did to clean that mess up (and to cause another?) I made two 2' cables with XLR on one end and RCA's on the other end. These are my main out (from pre) into the EV unit. I then made four XLR on one end, RCA's on the other end lines about 10' long. These went to each input of the amps. To wire the XLR/RCA cables, I used black as hot (or center, or what ever you might call it) Black is the pin on the RCA side and it's the bottom middle on the XLR side (or top middle, depending on perspective) The white and ground (weave) are grounded together on the RCA side to the shell. On the XLR side, the white & ground (weave) are on their respective posts. I guess now that I type that out, that might be my question. Will I need to go to each XLR plug and ground those two together? Do I need to bridge them or can I just move them to a single pin? Upon further typing and thinking... I think I now know I need to short the two out. Hopefully someone will chime in here and confirm. Thanks If I can't get rid of this SOON, I'll have to put that other mess back in. At least it worked!! [] Quote Link to comment Share on other sites More sharing options...
SilverSport Posted September 12, 2006 Share Posted September 12, 2006 c'mon...times a wastin' Bill Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 12, 2006 Author Share Posted September 12, 2006 Seems I had one of the wires soldered backward [:$] Not that I'm into confessions or anything like that. I fixed that wire and presuming I'm reading the schematis correctly, the wires are now either 100% right, or 100% wrong. Got frustrated so kicked the project. I guess we'll be using one RCA amp and one XLR amp this weekend. That's not so bad but I did want some leeway on what we used. now we're "stuck" having the MC-2102 in the system somewhere or another. Guess it COULD be worse? [A] Quote Link to comment Share on other sites More sharing options...
mark1101 Posted September 12, 2006 Share Posted September 12, 2006 http://forums.klipsch.com/forums/thread/559921.aspx Richard, Take a look at the link. IN that thread the very first post has an attachment which shows the correct pinnouts for converting XLR to RCA. Even I could do it. Quit breakin' stuff. [] Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 13, 2006 Author Share Posted September 13, 2006 Even I could do it. Quit breakin' stuff. [] You butting in here homeboy? Don't you have an ice cream cone or something like that you can go eat? [] [] Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted September 13, 2006 Share Posted September 13, 2006 Richard, I can't follow your description of the cable you made. Could you make a drawing / picture of the wiring showing exactly how you connected each wire ESPECAILLY the ground / shield connections at both ends. This sounds like a classic ground-loop. Al K. Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 13, 2006 Author Share Posted September 13, 2006 Hi Al, I've drawn it... see? (as I hold up a piece of paper with said drawing on it []) I DO think from the sound of it that you're right, it's probably a ground loop. I'm at work now so won't be able to read numbers and all... BUT, what I DO think I did was first, mistake that "black" wire represented hot. So, I had the "hot" black wire (mistake) go to the pin on the RCA plug. I twisted the white and sheath together and soldered them to the ground on the RCA plug. Now that Mike set me a bit further straight, rather than undo the RCA end, last night I went to the XLR end and moved wires on those terminals. I ended up swapping the white/black wires such that the black wire is now on (I think) pin #2 (but don't hold me to that yet) I've tested continuity and they all seem to test out fine, PRESUMING I'm reading the diagram from the correct perspective. I did end up making one of them a mirrored backward connection. Will delve into it more tonight when I get home. One other thing I'm going to try... remember that my main goal is to get rid of the XLR's on the McIntosh amp. I'm going to simply take THOSE two wires and see if I can swap them out for these XLR/RCA wires. If it works, I'm done. If it doesn't work I'll only have two wires to tinker with. As it was last night, I was dealing with six wires and some confusion. (was pushing 10:00 before I quit and I work much better in mornings) So, today I'll get a fresh start on it. Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted September 13, 2006 Share Posted September 13, 2006 Richard, I suggest that you use two single wire shielded cables and a third wire. Ground both shields and the wire to common ground at the source end. Connect ONLY the ground wire to common ground at the other (termination) end. Allow the shields to float at the terminatin end. This will see to it that no current flows through the shield. I really don't know what your cable is now, so this may be incompatible with what you are doing! Al K. Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 13, 2006 Author Share Posted September 13, 2006 Here's my highly scientific update [] Came home & was listening away. Remembered I was going to tinker so I took a SINGLE wire and swapped it out. (turned amp off, swapped, turned amp back on) I had no hum. Took a second one, swapped out... no hum. Third, fourth and so on. I don't get it. Last night, I swapped out six wires at once and had some blechy hum. Tonight, I swap them out one at a time (turning system back on in between to see which "one" caused the hum) and NOTHING!!??!! Oh, and get this. I once asked Mark Deneen about the Peach and why at "12:00" on the gain knobs I heard noise but turned down from there or UP from there, I did not. He said it was part of the circuit design, something about splitting signals and what not. Well, last night I had maximum noise when knobs were at 12:00 and minimum noise when they were cranked up. NOW the noise actually subsides a bit when I turn them closer to 12:00. Perhaps the XLR transformer was jacking the signal level up enough to make that difference? I'm not complaining but I'm sure confused. Perhaps in my tired state last night I was doing something really dufas like trying to plug an XLR cable end into my wall jack? [8-)] I've now bypassed the XLR transformer and my Peach outputs (RCA) go directly into the EV unit (XLR). The EV's four lines (XLR) exit the EV unit and go directly to two different amps (RCA). I think Al K intimidated them... either that or that other thread about Fini in a blonde wig and $200... Quote Link to comment Share on other sites More sharing options...
PrestonTom Posted September 13, 2006 Share Posted September 13, 2006 Hum can be a tricky thing to track down sometimes (many times actually). In my experience, folks will swap this & that and do whatever, followed by a good deal of superstitious behavior. Finally for some reason the hum goes away. At that point they throw up their hands and say: "ahh ha it was a ground loop" I am glad things worked out. BTW, one thing is bothering me. An expensive pre-amp (that can't be that old) should not be producing hum. It should be quiet. Something needs to be fixed... Good Luck, -Tom Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 13, 2006 Author Share Posted September 13, 2006 An expensive pre-amp (that can't be that old) should not be producing hum. It should be quiet. Something needs to be fixed... Just so it's said, I did call Mark about it. He explained it was how he designed the circuitry. It's way over my head but he said it was not to be unexpected that I'd hear more noise with the gains at "12:00". he further said something about "as the gain goes up and drawing on other stuff.... (ya, all over my head)" Aside from that, I ALSO had some scratchy noises in the gain knobs themselves (electronic scratchiness). He said I had the earlier (original) design and he'd since swapped versions/brands of pots behind the face plate because a number of people had been having this same issue. I sent it off to him for the upgrade and got it back just about a week ago. He told me he'd gone through it to be sure everything was ok. I'm sure if the 'noise' I refer to was an issue, that he would have caught and fixed it. I'm comfortable that all is well and operating as designed. Quote Link to comment Share on other sites More sharing options...
sunburnwilly Posted September 14, 2006 Share Posted September 14, 2006 You don't by chance have your Cable TV hooked into your system do you ? Quote Link to comment Share on other sites More sharing options...
oldbuckster Posted September 14, 2006 Share Posted September 14, 2006 What in Blue Blazes is Coytee carrying on about? What a whiner, has the Worlds Baddest Klipsch speakers and is still whining.......Some Cheese with that Wine??..My God Man..........get a Grip.........Just getting ready to show them Off.....They have a Hum....Poor baby.......Yes Coytee......You have the Biggest.................Speakers......There, nice way to start the day........Smile on my face.......Bye......Bass Boy.......................... I wish I had your Problems........................Dick......[]....[:$]....[:#] Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 14, 2006 Author Share Posted September 14, 2006 You don't by chance have your Cable TV hooked into your system do you ? I in fact DO have my DTV receiver set on the third Peach input. Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 14, 2006 Author Share Posted September 14, 2006 What in Blue Blazes is Coytee carrying on about? What a whiner, has the Worlds Baddest Klipsch speakers and is still whining.......Some Cheese with that Wine??..My God Man..........get a Grip.........Just getting ready to show them Off.....They have a Hum....Poor baby.......Yes Coytee......You have the Biggest.................Speakers......There, nice way to start the day........Smile on my face.......Bye......Bass Boy.......................... I wish I had your Problems........................Dick......[]....[:$]....[:#] OK Buckette... you're going to force me to humilate myself here... and tell you a story about "wine and cheese". My wife made a general appointment for me to go get a checkup at the Dr. (having been fairly healthy for 20 years and not being to see one). I go to the Dr like a good little boy. Hmm... it's a female Dr. No problem with that. WOW... she's got a KNOCKOUT nurse that works there. Killer brown eyes. They come in, take temp, kick my knees, make me cough [:$], hand me an empty cup. The nurse came back (alone) to take a blood sample [] [] The Dr. came back in shortly, handed me a gown and said to get into it. HUH??? "We'll be back in a minute to finish up" HUH?? hmmm... why a gown after all we've done??? HUH??? [*-)] [*-)] [*-)] [*-)] [*-)] [*-)] I do as ordered and the doc returns. Says to take the undies off too. HUH??? by now I'm getting a queezy feeling in my gut...as my suspicion level begins to rise (as opposed to...uh... never mind). Doc pulls out some gloves, says the Nurse will be in shortly as a witness. So let me see if I get this right... They're about to "violate" me and the nurse is going to be there as a protective witness that the doc what...??...??? didn't VIOLATE me??? is there some sick irony here? In comes the Babe nurse and I'm feeling smaller than spats on a centapede. Doc says lean over the bench, and I do so. As the "proceedure" was being ....well... you know... "done", I said... "you know Doc, when I take a woman out for the first time I always try to buy her dinner... the LEAST you could have done was have some wine & cheese here for me" I DO think they were about to cry from laughing... I'm not sure they expected that kind of a comment. Ok, so there's my humilty. I went in for "that" visit, had female Dr and a bombshell nurse and not the FIRST bit of wine & cheese. The cheapskates!! Now, what was your other issue?? [] Quote Link to comment Share on other sites More sharing options...
mark1101 Posted September 14, 2006 Share Posted September 14, 2006 Richard, Look, you already messed up the stereo, please leave the cable TV alone. I at least want to be able to watch some TV while I eat my hamburger and look at those Jubilees. At this point, I'm thinking that by the time we arrive the Peach will be broken, the system will have uncontrollable hum, and JC will refuse to connect his CD player.[] At least let us be able to watch some football. Have you fooled with the grill yet?......I'll just bring mine.[] [][] Quote Link to comment Share on other sites More sharing options...
Coytee Posted September 14, 2006 Author Share Posted September 14, 2006 Have you fooled with the grill yet?......I'll just bring mine.[] Where do you think I'm stashing all those XLR cables I removed last night? Wife wants them out of view, so I gotta hide them somewhere! [] Quote Link to comment Share on other sites More sharing options...
sheltie dave Posted September 14, 2006 Share Posted September 14, 2006 Coytee, inquiring minds want to know...... ring finger? Quote Link to comment Share on other sites More sharing options...
BiggerIsBetter Posted September 15, 2006 Share Posted September 15, 2006 Don't loose the cable thought. If the component that has the cable hooked into it is connected to your audio system, i.e. to listen to cable TV through your audio system, it can be a major source of hum. This type of hum is also typically intermittent and/or of varying loundness. Next time you hear the hum, just disconnect the cable from your cable box. Obviously, is the hum goes away your cable is the source. Is that's the case, call up your cable compan, show them that the cable is the cause, and make them fix it. Quote Link to comment Share on other sites More sharing options...
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