microphonic pickups

[BiRD_14]

Hi.. I've been having problems with my guitar pickups. They feedback like crazy if i turn up the volume, and if i tap my pick against them I can actually do a little percussion bit cos the sound of the tapping gets picked up (no pun intended). It's a bother cos i do play a fair bit of overdrive/ distortion..

Talked to ark and ciel about this before, and they said it had sth to do with microphonic pickups. Any solutions besides changing the pickups that you guys may have? Kinda holding out for a DL4 so... ya kinda broke.

Erm if it helps my guitar is an '91 MIK Epi LP Custom (or at least the internet says so)

Thanks for your help!

 

[0vid]

Other tha changing pickups you can put your pickups through a 're-potting' process. This invovles dipping your pickups in wax individually. Theoretically this reduces vibrations and consequently reduces, feedback. The feedback process is due to a number of things, resosonances peaks of your pickups, resonance peaks of your amplification set up, and where, what and how you play.

http://www.projectguitar.com/tut/dip.htm

If you have decent technique you could have it kept it under control. I doubt your pickup is as microphonic as typical 60's cheap guitars- you can literally sing through the pickups on those - try this and if you don't hear your voice coming through your amp easily, you really should just keep it in check with technique.

 

[JiveB]

I don't think microphonic pickups are limited to cheap guitars.. I had a friend with an RG Prestige that he made sounds through for fun, granted not singing. And we used my friend's strat with Nordys on them to amplify the ipod earphones when we needed to broadcast an idea to the band.

Just a general view though. 8)

 

[BiRD_14]

I'll think about the re-potting process. Thanks!

The feedback process is due to a number of things, resosonances peaks of your pickups, resonance peaks of your amplification set up, and where, what and how you play.

Hmm is there any way I can find out about the resonance peaks of my pickups? I have no idea what they are or where they are from cos of the guitar's age.. I can't really control the amp much though, cos when you gig or jam you pretty much take what they give you.. ditto for the where i play part.. i do understand that playing my fair bit of od/dist doesn't help heh

I roughly understand how feedback works on a general level, so i do try to control where i position myself and the above mentioned, but once i reach a certain volume level it just gives me trouble.. I can only stand so far from the amp ha..

If you have decent technique you could have it kept it under control with technique. I doubt your pickup is an microphonic as typical 60's cheap guitars, you can literally sing through them - try this and if you don't hear your voice coming through your amp easily, you really should just keep it in check with technique.

It doesn't really pick up my voice but does pick up the 'f's and 'p's, not to mention when i blow on them - sounds like white noise..
Hmm what do you mean by technique? Any personal tips then?

Anyway thanks so much for helping!

 

[BiRD_14]

I don't think microphonic pickups are limited to cheap guitars.. I had a friend with an RG Prestige that he made sounds through for fun, granted not singing. And we used my friend's strat with Nordys on them to amplify the ipod earphones when we needed to broadcast an idea to the band.

Just a general view though. 8)

That's cool! What kind of sounds have you guys tried? Maybe i can experiment myself ha..

 

[JiveB]

Those stupid noises that you make when you're bored.. with your mouth.. 'weeeee' 'woooooo' 'weuweuweu' are some examples.

/lame 8)

 

[bockscar]

hmmm sometimes when i play the higher note strings, i hear some picking soud from the amp

is this a result of microphonic pickups?

 

[MackSonne]

Have u muted the unwanted strings? Some strings will vibrate other strings withou touching.

 

[0vid]

A magnetic pickup is made of magnets and a coil, or coils in humbicking designs. If you know your Faraday's law, you will know that as long as there is relative movement of the coil to the magnet, there will some induction of emf.
A change in the magnetic environment of a coil of wire will also cause a voltage (emf) to be induced in the coil. This change could be produced by changing the magnetic field strength, and can be caused by moving a magnet toward or away from the coil, moving the coil into or out of the magnetic field, rotating the coil relative to the magnet, vibrating a taut metal string close to the coil, or by simply tapping the coil/magnet.

Potting, i.e. engulfing the coil in wax, reduces vulnerability to vibrations caused by tapping , loud volume, or sympathetic resonance. These result in a loud tap, or feedback respectively.

A microphonic pickup is one where there is usually a thin diaphram, somewhere in the construction prone to vibrations. This could be a thin metallic pickup cover. Efffectively this vibrates and can transmit those vibrations to the coil/magnet and you may get an audible sound, amplified that you may recognise as a vocal sound if you shout into the pickups. Effectively these pickups are very primitive microphones. Sometimes, very thin hollow body tops offer this to the pickup, they pickup vibrations and transfer them to the pickup via sympathetic resonance.

Plastic covered pickups suffer from microphonic effects less than thin metal covered ones, though thin plastic covers allowed to freely vibrate can also induce EMF. Your typical modern pickup design, - say Bartolini, or EMG - are hermetically cast into resin, so the effects of feedback are minimised , but not eradicated completely.

All pickups are susceptible to tapping. If you tap a pickup and get no 'tapped signal' when you amplify the instrument - your pickup is dead. You can palm mute your strings and you would still get a signal even if you dampen the strings, so pickups can generate signals even with the slightest encouragement to induce EMF.

Your typical microphonic pickup which you can sing through cn be found on old Hofners, Teisco, Kent, Univox etc....

 

[thebassplaya]

my bass pickup oso, cannot turn the volume up or else will feedback like mad, making whistling sound...

im not even playing anything, so its nothing to do w technique...

anyone knows where 'potting' can be done? and for how much $$$?

 

[BiRD_14]

If you know your Faraday's law, you will know that as long as there is relative movement of the coil to the magnet, there will some induction of emf.

Faraday was as long ago in my memory as when Luthermusic was still in IMM heh.. But ya I catch your drift..

A microphonic pickup is one where there is usually a thin diaphram, somewhere in the construction prone to vibrations. This could be a thin metallic pickup cover.

Mine is a metallic cover, so I guess it's a prime possibility.. Thanks for the info and suggestions ya..

Have u muted the unwanted strings? Some strings will vibrate other strings withou touching.

Yup, i do mute the strings that I am not playing.. It helps but like 0vid said it can still be susceptible..