Results 1 to 4 of 4
Like Tree1Likes
  • 1 Post By big_teee

Thread: Microphonic Feedback After Wax Potting

  1. #1
    Junior Member
    Join Date
    Aug 2017
    Posts
    8

    Microphonic Feedback After Wax Potting

    Greetings All -

    tl;dr - I wax potted my Rickenbacker Toaster pickups but still have really bad microphonic feedback. What can I do now?

    I recently installed Rickenbacker Toasters into my 650D. At practice volume, the guitar sounds very nice. Just enough of the classic jangle of the toasters but the natural walnut balances the sound nicely. But then I brought the guitar to a sizable gig and cranked my 59 LTD Bassman to 6 and squeal city!! These toasters are terribly microphonic.

    I purchased these from a licensed dealer (Chicago Music Exchange) and they were brand new. But because I had soldered them, no refunds. I spoke to their techs and they recommended I get them wax potted which was consistent with the advice I've seen given to others on this forum.

    So now they are wax potted. Still sound beautiful at low volume/gain but still getting the high pitched squeal. I'd read that wax potting was the cure for microphonic feedback but apparently that's not the case. I also tried the ISP Decimator II which did not reduce the squealing. Finally, I tried tuning out the offending frequency on the amps but had to take treble to 0 - not viable.

    Before I start trying some of the other tricks I've read about on some of these forums, I wanted to check in with you knowledgable folks to see if there's anything I'm missing. I'm getting the feedback with 2 different amps and 2 different overdrive pedals. It's definitely microphonic (bad) feedback. I took it to a very good amp tech who confirmed both pickups were microphonic. Both produce the squeal at a reasonably loud volume or with gain.

    One thought is that when installing, I used the screws that came with the 650D instead of what shipped with the Toaster pups. I did this because the Toaster screws were a bit longer and I didn't want to have to drill into the 650D. Could the screws be vibrating or otherwise contributing to the problem?

    I've read that using poster putty between the pickup and the pickup cover can fix this problem. The cover on the toaster is not soldered on but is held on by bolts which I've heard can result in vibration causing squeal. Is this recommended? I've also heard that melting some wax between the cover and pup can help in the same way.

    I've also seen folks will put foam or some other insulating material in the pickup cavity. Some say it's to absorb some of the high frequencies in the cavity and others say it's to keep the pup from rattling around in there. I have rubber grommets between the pickup and the guitar wood so theoretically, the latter would not be a problem. Hoping the truth is the former. I have some high frequency sound absorbing foam (wall panel/foam wedge) but have also read that folks recommend something denser like a mouse pad. What's the recommended material?
    er idea I've seen is around adjusting the screws. I've seen recommendations to either loosen (so the pup doesnít pick up the body vibrations) or tighten (so the pup doesnít rattle around). Iíve also seen a recommendation to place a rubber washer between the screw and the pickup cover so it is less coupled to the guitar. Which (if any) of these are best?

    Finally, Iíve read mixed advice around potting. Some folks have said if the microphonic arenít fixed by one round of potting, to do it again with more wax (more time to soak, more to dry, etc.) But Iíve also read that over-waxing will kill the tone of a pickup, something I definitely donít want to do. Would it be worth waxing these Toasters a second time?

    Kind of crazy that such expensive electronics would have such trouble in high volume/gain situations. The tech that potted the pups said this is to be expected with some of the Ric pups. Anyone else have this experience?

  2. #2
    ToneOholic! big_teee's Avatar
    Join Date
    Jun 2010
    Location
    Mid-South USA
    Posts
    9,653
    I got him to repost over here.
    The question I have on Ric Toasters?
    Do you pot coils only, or can you pot coil, cover, and the whole kit and caboodle, at one time?
    Ric rewinders, please advise!
    Thanks,
    T
    copperheadroads likes this.
    Technicians Run the World, but Bankers, Lawyers, and Accountants, Take All The Credit!
    Keep Rockin! B_T
    Terry

  3. #3
    Supporting Member
    Join Date
    May 2006
    Location
    PDX
    Posts
    3,172
    If these are wound with 45 or 46AWG then the wax may be having a tough time getting into the coil. I don't know that for a fact but it stands to reason. Vacuum potting might help. It's also possible that it has nothing to do with the coils. Just the cover or the baseplate or other metal parts could be flexing and causing the squeal. I find that tapping on the pickups can help me locate where the problem is coming from and then I can tackle it.

  4. #4
    Pickup Maker David Schwab's Avatar
    Join Date
    May 2006
    Location
    Staten Island, NY
    Posts
    10,924
    Toasters are 44 AWG. I never have a problem with wax getting in.

    My guess is the metal cover is vibrating. Try to put some damping material between the cover and the bobbin. Even wax should work.

    Also, check for loose magnets.
    It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. ó Albert Einstein

    www.sgd-lutherie.com
    www.soundcloud.com/davidravenmoon
    SGD Lutherie Facebook page

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Microphonic Feedback After Wax Potting
    By dcmusic in forum Music Electronics
    Replies: 12
    Last Post: 08-27-2017, 08:49 PM
  2. What potting wax mix?
    By 888guitars in forum Pickup Makers
    Replies: 20
    Last Post: 01-15-2017, 05:51 PM
  3. Taping before, and after wax potting
    By LVS in forum Beginner/ Hobbyist
    Replies: 5
    Last Post: 09-16-2015, 10:21 PM
  4. Wax potting under $20!
    By R.Madgwick in forum Beginner/ Hobbyist
    Replies: 6
    Last Post: 01-09-2015, 04:53 PM
  5. Wax Potting
    By texan in forum Pickup Makers
    Replies: 20
    Last Post: 02-27-2008, 01:32 AM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •