squealinga and feedback

Mon Nov 15, 2010 11:38 pm

Hello everybody! I recently bought an ASAT classic from 1998 (smaller MFD's). I had tried ASAT's before (a brand new one from 2008 i guess) and loved the MFD's sound, my asat isn't an exception but...
Here we go with the issues... when I bought it, the neck pickup had been replaced with a HARMONIC DESIGN mini strat for tele model, the original MFD pop was included In the case so i put the back.
The sound is fantastic however I have a feedback problem that especially happens with the bridge pickup, even though for some reason it has a lot less gain than the neck one???
I read on another forum that the issue is actually the bridge and not the pickups?? that putting double sided tape/melted wax under the front end of the bridge fixes it?
The problem is that English is not my first language so I don't get the entire point of the solution... Does it mean I need to remove the "ash-tray" bridge and put some tape underneath the front (closer to the neck I assume??) or is it under the strings' saddles (hopefully saddle is the right word...)
Also cause if this difference in gain/volume (neck pop louder than bridge) the middle position sound very "nasal," I don't know how to describe it but the middle position doesn't sound good at all now...
I hope that somebody can throw some light on the subject. Thanks!

Re: squealinga and feedback

Tue Nov 16, 2010 12:15 am

Welcome,
here is a thread that discusses pickup squeal:
http://www.guitarsbyleo.com/FORUM/viewtopic.php?f=13&t=1650

I would think you would apply the material (wax or tape)evenly under the front and back of the bridge to keep things level.
If that doesn't fix the squeal , you night need to pot the pickup in wax.
Is it possible the bridge pickup was replaced? that might account for the mismatched outputs.

Re: squealinga and feedback

Tue Nov 16, 2010 12:25 pm

I don't know enough to advise you on the squealing issue, but the "nasal" sound of the middle position sounds like perhaps you have the pickups wired 'out of phase'.

Re: squealinga and feedback

Tue Nov 16, 2010 6:52 pm

Thanks for both replies! I already bought some double sided tape and will give it a shot. A friend of mine did the replacing of the pickup so I'l try to find a wiring diagram online and check it myself, thanks!!!

Re: squealinga and feedback

Tue Nov 16, 2010 8:08 pm

Uhhh this is more complicated than what I thought it would be... since the other guy change the pickup I don't know how it was wired before... any hints on how to fix the Phase issue???

Re: squealinga and feedback

Tue Nov 16, 2010 8:29 pm

Elwood wrote:Welcome,
here is a thread that discusses pickup squeal:
http://www.guitarsbyleo.com/FORUM/viewtopic.php?f=13&t=1650

I would think you would apply the material (wax or tape)evenly under the front and back of the bridge to keep things level.
If that doesn't fix the squeal , you night need to pot the pickup in wax.
Is it possible the bridge pickup was replaced? that might account for the mismatched outputs.


I just added another related post in the same sub-forum: My MFD went massively microphonic! Suggestions?

Hope this helps.

Re: squealinga and feedback

Tue Nov 16, 2010 9:17 pm

suave eddie wrote:I don't know enough to advise you on the squealing issue, but the "nasal" sound of the middle position sounds like perhaps you have the pickups wired 'out of phase'.


So coming from the neck pickup I have the Black wire soldered to the 3 positions switch and the white wire soldered to the back of the volume pot, as ground I assume, should I reverse those???

Re: squealinga and feedback

Tue Nov 16, 2010 9:21 pm

Craig wrote:
Elwood wrote:Welcome,
here is a thread that discusses pickup squeal:
http://www.guitarsbyleo.com/FORUM/viewtopic.php?f=13&t=1650

I would think you would apply the material (wax or tape)evenly under the front and back of the bridge to keep things level.
If that doesn't fix the squeal , you night need to pot the pickup in wax.
Is it possible the bridge pickup was replaced? that might account for the mismatched outputs.


I just added another related post in the same sub-forum: My MFD went massively microphonic! Suggestions?

Hope this helps.


Thanks, a quick question. I have been trying to find parafin/canning wax specifically but only found wax that comes in blocks to make candles, I assume it is not the same??

Re: squealinga and feedback

Tue Nov 16, 2010 10:53 pm

betocosano wrote:
Craig wrote:
Elwood wrote:Welcome,
here is a thread that discusses pickup squeal:
http://www.guitarsbyleo.com/FORUM/viewtopic.php?f=13&t=1650

I would think you would apply the material (wax or tape)evenly under the front and back of the bridge to keep things level.
If that doesn't fix the squeal , you night need to pot the pickup in wax.
Is it possible the bridge pickup was replaced? that might account for the mismatched outputs.


I just added another related post in the same sub-forum: My MFD went massively microphonic! Suggestions?

Hope this helps.


Thanks, a quick question. I have been trying to find parafin/canning wax specifically but only found wax that comes in blocks to make candles, I assume it is not the same??


It is the same paraffin wax. Note that Gabe uses a mix of 90% paraffin and 10% bee's wax.

Hope this helps.

Re: squealinga and feedback

Tue Nov 16, 2010 11:43 pm

Craig wrote:
betocosano wrote:
Craig wrote:
Elwood wrote:Welcome,
here is a thread that discusses pickup squeal:
http://www.guitarsbyleo.com/FORUM/viewtopic.php?f=13&t=1650

I would think you would apply the material (wax or tape)evenly under the front and back of the bridge to keep things level.
If that doesn't fix the squeal , you night need to pot the pickup in wax.
Is it possible the bridge pickup was replaced? that might account for the mismatched outputs.


I just added another related post in the same sub-forum: My MFD went massively microphonic! Suggestions?

Hope this helps.




Thanks again and last question, sorry :shocked028: I assume it is not possible to pot The neck pick up cause it is covered in plastic right? unless the bottom is open? the bridge pick up has a plastic cover, is it possible to remove that? would it be damaged by the high temperature?

Re: squealinga and feedback

Wed Nov 17, 2010 8:13 am

betocosano wrote:Thanks again and last question, sorry :shocked028: I assume it is not possible to pot The neck pick up cause it is covered in plastic right? unless the bottom is open? the bridge pick up has a plastic cover, is it possible to remove that? would it be damaged by the high temperature?


While Gabe does make it sound easy, re-potting a pickup must be done with care, caution and proper equipment.
You could easily damage the pickup due to incorrect heating of the wax, allowing the pickup to rest on the hotter
sides or bottom surfaces of the pot, or while removing the pickup cover from the pickup which could break the
delicate coil windings which might be stuck to the cover with existing wax.

As Gabe says, you might consider sending your pickup out to get vacuum/pressure potted because you get much
better coil pack saturation this way. All sorts of pickup builders offer this service for around $10/pickup.

Goggle "pickup rewinding service" for current offering of this service.

My recommendation is to have this done by a professional service.

Hope this helps.