Explain 'microphonic' pickups to me

Discussion in 'Guitars in General' started by mikenixon316, Feb 26, 2008.

  1. mikenixon316

    mikenixon316 Member

    Messages:
    105
    Joined:
    Oct 24, 2007
    Location:
    Leeds, England
    I was rehearsing with my band today in a rehearsal studio and had my 80's MIJ strat plugged into a twin reverb. When I stopped playing I noticed that I could hear the vocals from another band, who were rehearsing down the hall, coming through the amp. When I turned my guitar volume down it dissappeared. I deduced from this that my pickups were picking up the signal from their microphones. Surely that's not normal. Is that what's meant by the term 'microphonic'?

    Is this something that all strat pickups suffer from or just mine?
     
  2. Jellecaster

    Jellecaster Member

    Messages:
    184
    Joined:
    Jul 24, 2007
    It's not so much that they are picking up the signal from the microphones - they are actually acting LIKE microphones. It's not unusual, but not all pickups are microphonic.

    One of my Teles (I don't play Leo's "other" guitar) was acting like this so I replaced the pickups. Any time my fingers would brush the bridge it was very audible.
     
  3. Pete Galati

    Pete Galati Member

    Messages:
    1,685
    Joined:
    Jan 9, 2006
    A lot of players find that very desirable. Some of the good Telecasters, you can talk into the pickups, and hear yourself in the amp.

    I have a couple guitars with unpotted Duncan '59 pickups. It's less problematic in my Les Paul Standard, where I opened up the neck pickup to flip the magnet for the Peter Green thing. Has something to do with how I remounted the cover, and the solid nature of that guitar. My gold Tele with unpotted Duncan '59s has a lot more problems if I use much gain. But I generally like unpotted pickups a lot because they're a lot less dead.

    I think your playing situations determine how well you can live with microphonic pickups. Much as I like microphonic pickups, they can turn into a guitar's biggest weakness.
     
  4. RvChevron

    RvChevron Member

    Messages:
    2,467
    Joined:
    Jan 7, 2002
    Location:
    Hong Kong, China
    A microphonic pickup will act like a microphone but it can't be picking up anything from that far way.

    In your case, it seems more like the pickup is picking up radio frequency or EMF. It might be the wiring of the place you rehersed.

    Could also be the pedals or the amp, not that there's anything wrong with them if you play somewhere else with clean wiring.
     
  5. stratrat2000

    stratrat2000 Member

    Messages:
    274
    Joined:
    Mar 12, 2006
    Location:
    Darkest Africa
    Microphonics are when a pickup tends to pick up acoustic sound. At high volume this can cause pickup squeal - an uncontrollable feedback that does not involve the vibration of the strings.

    All pickups are microphonic to some degree. The more heavily potted (the coils saturated in wax) they are, the less microphonic they are. Some styles of pickup sound better if they are slightly microphonic as they pick up more of the guitar's acoustic tone, which adds a degree of complexity to the tone.

    However, I'm willing to bet that what you are describing is not microphonic pickups - more likely the guitar, your amp or cable is picking up RF (radio frequencies) from wireless mics. You only heard the vocals from the other band, right? And you could not hear the other band loudly through the wall? If your pickups were that microphonic, you would be able to sing into them and hear it.

    You need to track down exactly where the RF is being picked up. Turning down the guitar's volume will stop it, regardless of the source as it effectively grounds the guitar, cable and amp. Try a different cable and guitar and see if either makes a difference - if not, it's the amp.

    If it's the guitar, it can be screened to prevent this. If it's the amp, it will need the input circuit modifying by a pro. The cable would be a simple case of replacing.
     
  6. guitardr

    guitardr Silver Supporting Member

    Messages:
    971
    Joined:
    Nov 15, 2007
    Location:
    Chicago
    I once had a wonderful '58 Les Paul Standard that had PAF's that were microphonic "+". The lead sinder from the Shadows of Night, Jim Sohns, jumped up on stage at a suburban club once and started singing into the pups. Funny!

    Just a slightly deteriorating characteristic of certain PU's. The copper winding becomes progressively polarized/magnetic from the magnet. With the realtively poor or non-existent shielding in guitar cavities adding to the phonic factor (and maybe a cable that's lost it's 'way'): local cab drivers, two-way communications, negative RF and Radio Free Europe are all witrhin reach. LOL
     

Share This Page