RCA to XLR confusion, help me figure this out...

Discussion in 'Home Theater Projects' started by Norm12345, Jan 6, 2012.

  1. Norm12345

    Norm12345 Auditioning

    Joined:
    Dec 9, 2011
    Messages:
    11
    Likes Received:
    0
    So, I've decided to use my JL 12W7 subwoofer for my hometheater instead of having it in a "waking up the neighbours car". I tried using my Yorkville AP4040 amplifier, but that didn't work, since its only a 4ohm amp and the JL is a 3 ohm speaker... Anyhow, long story short, I ended up buying a Crown CE4000, my friend was running this amp for this speaker before so I know it should work. I got a cable from monoprice to convert my RCA pre out for the subwoofer to an XLR. I first noticed that there was arrows on the cable, and thinking about, the arrows are going the wrong way on the cable, so I'm thinking this cable is directional,.... nevertheless my friend told me to just try it, worst case its out of phase and I'd just have to invert it on the receiver. So tried it... and yeah, not working... So I took the cable apart, first thing I noticed was the ground wire and + wire a the opposite from the pin output from the Crown manual, this cable is reversed. From what I can tell... Looking at the cable with middle pin at the bottom, Pin 1 is on the right, and it has a black wire attached to it... I think this is the + wire. Pin 2 has a clear wire, thinking this is the - and Pin 3, on the left, is the ground shield. If my assumptions are correct, then the + wire and the ground wire are reversed... How can I tell for sure using an multimeter which wire should go on which connector? Thanks,
     
  2. Wayne A. Pflughaupt

    Joined:
    Aug 5, 1999
    Messages:
    6,043
    Likes Received:
    17
    Location:
    Katy, TX
    Real Name:
    Wayne
    Sounds like the cable is indeed wired backwards. Continuity check with a multimeter should be as follows: RCA tip (signal + ) to XLR pin 2 RCA sleeve (signal - ) to XLR pin 3 If the XLR pin 1 has a connection, it should be the cable’s shield. If that’s the case, there should be continuity between pins 1 and 3. If you have noise (hum) issues, try lifting the pin one connection. Regards, Wayne A. Pflughaupt
     
  3. Norm12345

    Norm12345 Auditioning

    Joined:
    Dec 9, 2011
    Messages:
    11
    Likes Received:
    0
    crap, I thought it would of been just as simple as swapping pin 1 and 2, but I was wrong... I swapped them and now I get Tip + -> pin 2 Ti[p - -> pin 3 sleeve shied -> pin1 would this work using the RCA pre-out sub jack into a power amp?
     
  4. Norm12345

    Norm12345 Auditioning

    Joined:
    Dec 9, 2011
    Messages:
    11
    Likes Received:
    0
    Ok, First of all., I should correct myself that the pin assigment I said in my original post was not correct Pin 3 is the bottom center pin, pin 2 is on the left and pin 1 is on the right... There's 3 wires... Black, clear and shield... Originally it was wired like this,... Pin 2 was the shield wire Pin 3 was the clear wire pin 1 was the black wire in a balanced or unbalanced cable, Crown has the shield wire going to pin 1, the (-) wire going to pin 3 and the (+) wire going to pin 2,which to me meant that the black wire on pin 1 was in the wrong position, and most likely the (+) so I simply rewired it so the black wire is at pin 2 and the shield is at pin 1. This is what I get:in continuity tests Pin 1 = sleeve pin 2 = tip pin 3 = tip pin 2 = pin 3 plugged it in and all I hear is a loud hum from the sub.YPAO didn't pick it up either... what should I try next?.
     
  5. Wayne A. Pflughaupt

    Joined:
    Aug 5, 1999
    Messages:
    6,043
    Likes Received:
    17
    Location:
    Katy, TX
    Real Name:
    Wayne
    Sounds like you’ve shorted out Pins 2 and 3, which is the signal (+) and (-). No wonder it doesn’t work, that’s the same thing as shorting out the tip and sleeve of an RCA cable. Your cable should be wired as I described out in my previous post. Here is a visual diagram, if that helps - see Drawing #17. Regards, Wayne A. Pflughaupt
     

Share This Page