RTiA9 Crossover Problem? Help me diagnose it!

Inspector 24
Inspector 24 Posts: 1,308
edited January 2012 in Troubleshooting
I noticed over the last couple weeks of listening there seemed to be a left bias to the sound, vocals and higher frequencies seemed to be attached to the left speaker. I found this odd as a hearing test a few months ago revealed that my right ear is much more sensitive to upper mid range and lower treble frequencies than my left. Running the YPAO on the receiver as a check showed the right speaker needing few DB more in these frequencies, and a bit more volume. Listening to each speaker independently confirmed there was a difference, and it seemed to be all in the tweeter.

I'm an automotive technician by trade with a big focus on diagnostics so I'm no stranger to taking things apart and testing them so I dove in with some resistance tests on the tweeter and from it's wires to the binding posts here's what I've found.

Circuit Left Right
Tweeter 2.9-3.0 ohm 3.0 ohm
White to Pos 8.8 ohm 1.2 megohms and dropping
White to Neg .6 ohm .6 Ohm
Blue to Pos 8.4 ohm .68 megohms and rising?
Blue to Neg .2 ohm .2 ohm

It appears to me the right has a capacitor that is charging/discharging as the meter sends a current through it, where the left has no change at all, however however I admit crossover networks are a bit above my head, and more complex that what I deal with on a regular basis so beyond that I'm stumped... I visually inspected both crossovers as good as possible (wouldn't come out all the way, wiring too short) and didn't see any obvious broken solder joints, cooked boards or leaking capacitors, so, where do I go next, or is the answer as simple as the board is bad and needs replaced...if so, which one?? :eek:

Any input is GREATLY appreciated!!
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Post edited by Inspector 24 on

Comments

  • BeefJerky
    BeefJerky Posts: 1,320
    edited January 2012
    First thing you need to do is try swapping the tweeter between the two speakers and see whether the problem follows the tweeter or not.

    If it doesn't follow the tweeter, than you need to try swapping the speakers around. If it follows the speaker, then the crossover is the problem. If not, that would indicate a problem with the wiring, receiver, or source.
  • Inspector 24
    Inspector 24 Posts: 1,308
    edited January 2012
    So much for jumping to conclusions.

    I started swapping and sure enough tweeter was fine, and the problem followed the speaker wire when swapped, then swapped wires at the amp and the problem disappears all together, wtf bad connection? Pulled the banana plugs apart, couldn't see any problems but I cut back the wire and re-did them all anyway, after which I did a through wiggle test of the connections and wires and found no more problems, once again they sound great!

    I would not have guessed the loss of high frequencies would be a bad connection.

    However, that doesn't explain the huge difference in readings with the multimeter, still a possible crossover going out??
    Up
    LSi15 LSiC - RX-V3000

    Down
    LSiM707 - 706c - 702f/x - Dual HSU VTF-15H Mk2
    Parasound HCA-3500 - HCA-2003A - Marantz SR7005
    Sim2 D60 - Dragonfly 106" Panny 500