Why can I hear tapping on my RCAs??

Rev. Hayes
Rev. Hayes Posts: 475
edited January 2011 in DIY, Mods & Tweaks
This personal confusion started when I rewired the tonearm in my sl-1210.

At first all seemed to have gone well but then I realized that my arm had gone seriously microphonic (even with the cart disconnected). I could even hear the wires moving inside the tube as I moved the arm. After a great deal of frustrating trouble shooting I decided to pull the whole thing apart and track the problem down from the headshell socket all the way back.

Result: I'm all the way back to just the RCA's and sure enough, a tap tap tap on the cable itself is coming trough the speakers.

I was under the apparently false impression that this should not be possible. How can insulated wire alone act like a mic.


Weirdest thing: My friend and I did this project together at the same time. Same table, same wire, I have this microphonc issue and he doesn't.

I think I'm going nuts here.
Sounds good to me...
Post edited by Rev. Hayes on
· Share on FacebookShare on Twitter

Comments

  • george daniel
    george daniel Posts: 12,096
    edited January 2011
    what kind/type of cable are you using?
    I assume you are talking about the phono cable from the tt to the phono pre/board?
    JC approves....he told me so. (F-1 nut)
    · Share on FacebookShare on Twitter
  • Rev. Hayes
    Rev. Hayes Posts: 475
    edited January 2011
    It's (gulp) Monster Interlink 250.

    I had seen a posting of someone else's mod using this wire and they claimed to have good results. I happened to have some in a bag that came with a system I bought off of CL, so I used it.



    Anyway, I'm currently halfway done putting it all back together. I wrapped the wire in the tube with teflon tape hoping that might help. I don't know.....
    Sounds good to me...
    · Share on FacebookShare on Twitter
  • george daniel
    george daniel Posts: 12,096
    edited January 2011
    If that does not fix the issue,,try using a pair of the IC's that come with dvd and cd players instead and see if you get an inprovement,,they are shielded,,if that works,I see some new IC's in your future.Good luck,,keep us posted.Oh,, do you have your tt grounded?
    JC approves....he told me so. (F-1 nut)
    · Share on FacebookShare on Twitter
  • dcmeigs
    dcmeigs Posts: 708
    edited January 2011
    I think you will find that George is right about the cables but there is another possibility, perhaps number two on the list. Is your turntable grounded to your phono preamp or receiver. (That needs to be done with most turntables). No or poor grounding usually causes hum BUT a failing return in the cable combined with lack of grounding might cause this. How does it sound when played? Weak and scratchy in one channel perhaps?
    The world is full of answers, some are right and some are wrong. - Neil Young
    · Share on FacebookShare on Twitter
  • Rev. Hayes
    Rev. Hayes Posts: 475
    edited January 2011
    george daniel wrote: »
    try using a pair of the IC's that come with dvd and cd players instead and see if you get an inprovement

    that is funny...:tongue:


    Ok, all the soldering is done and.......

    The tube is now silent!!!

    I can tap on it to my heart's content and hear nothing.
    I'm not sure if this is a result of fixing a bad solder joint or the tape but right now I don't care.

    But, and you monster haters are going to love this, tapping on the RCAs is still causing a little poping noise. It seemed like good wire. (oxygen free copper, foil shielded, nice terminations) I guess I'll throw the stock wires back on for now.
    Sounds good to me...
    · Share on FacebookShare on Twitter
  • Rev. Hayes
    Rev. Hayes Posts: 475
    edited January 2011
    I got this interesting response from Coffee Phil over at Vinylengine.
    Just thought I'd share it here.

    "Cables can indeed act as microphones. Some polymers as well as ceramics have piezoelectric properties. You may remember the Pioneer HPM tweeters which operated on that very principle. I have seen some "high end" cables do this. I thought it was funny that they didn't check that out before selling the cables and hyping them as something great."
    Sounds good to me...
    · Share on FacebookShare on Twitter
  • george daniel
    george daniel Posts: 12,096
    edited January 2011
    thas why i said to try the cheapo cables,,they are shielded,,if it cures the ilness,,then an upgrade(cable) is in you future.Make sure the tt is grounded,usually to the pre,,,another trick is to solder some bradley resistors at the input ground to ground,, moves the noise to a different plane--old george wright tweak.
    JC approves....he told me so. (F-1 nut)
    · Share on FacebookShare on Twitter
  • FarmVille
    FarmVille Posts: 1
    edited January 2011
    get farm cash farmville
    There could arrive a time, even though, when you want to get a small much more out of the game. Just about every time you transfer up a stage, you unlock new seeds, decorations, and other discretionary items. This signifies that in purchase to get the most out of your FarmVille experience, you'll have to stage up swiftly to unlock as a lot of goods and bonuses as you can.
    farmville sunflower
    · Share on FacebookShare on Twitter
  • Joe08867
    Joe08867 Posts: 3,919
    edited January 2011
    Spam Reported
    · Share on FacebookShare on Twitter