Microphonic PUs: what does it mean?
Carlo Pipitone
Hi,
I recently read a posting about "microphonic pickups": what does it
mean?
I know that a microphonic amp tube is one which "sounds" when you
slightly hit it.
PLEASE reply also to carl...@tin.it
--------------
Carlo Pipitone
Palermo, Italy
Ivar Arnesen
Carlo Pipitone wrote in message <355312f9...@news.tin.it>...
Carlo, this happens when a pickup is constructed badly, apply some volume
and/or distortion, and it will start making whistling noises that are
anything but musical. I have a Samick jazz-guitar that sounds fine when the
volume is down, but increase volume or gain, and all hell breakes loose.
The solutions are usually two:
Either get some decent pickups, or have a good repairman dip the pickups in
wax, which solidifies the coils, and stops the noise.
If you like the general sound of the pickups, go for solution two, like I am
planning to do. But usually you would be better of getting a pair of good,
name-brand pickups.
This usually happens on cheap guitars, bur can affect older, more exspensive
ones as well!
Ciao;
Ivar Arnesen
Oslo, Norway
Patrick Keenan
The explanation is pretty much the same - the pickup, as the tube, responds
audibly to vibrations. In the case of a pickup, it'll usually squeal, and
this is the result of loose windings, bobbin components, or any other part
of the assembly being loose. It can be just a metal cover, if it has one.
Typical fixes involve 'potting' the pickip by soaking it for a period of
time in melted parrafin wax. The wax must penetrate, but must not melt
anything. If it's the cover, solder may help.
This is not without risk; the wax is flammable, so always use a
double-boiler to melt it; and as mentioned you may not melt the coil
bobbins. Use the perfect-toast rule: till it burns, then ten seconds less.
I have never seen Epoxy used successfully for this purpose. What it was
successful at was making sure the pickup could never be fixed.
--
Thanks!
Patrick Keenan
Symantec
============
Thurston >
> I have never seen Epoxy used successfully for this purpose. What it
> was successful at was making sure the pickup could never be fixed.
EMG uses epoxy and I think it works really well. Carvin also epoxy dips
their pickups. I believe Seymour Duncan also epoxy dips their active
pickups.
Patrick F. Coleman
Thurston <"<john_thrush"@ncsu.edu>> wrote:
Yep...
and you can check out donald brosnacs book Guitar Electronics for lots
of tips and tricks on guitar customizing and modifications.. it's
payed for itself for me time and again.. clear easy to understand and
very comprehensive...
try http://www.stewmac.com or
http://www.jumpnet.com/~musicianworkshop
for prices on the book
or try your local library with free interlibrary loan and see if you
can get it, or seveal other books on guitar electronics to read
through before purchase...
I really recommend you learn all you can about this stuff... there are
several methods for reducing microphonics for different circumstances,
etc.
twang!
patrick f. coleman
TWANG!
http://members.wbs.net/homepages/t/w/a/twangme.html
http://members.wbs.net/homepages/t/w/a/twangin.html
http://members.wbs.net/homepages/t/w/a/twangon.html
NOCTURNAL10
Epoxy does more to ensure that the PU cannot be reverse engineered than
anything,A hard wax works just as well.
Thurston > <" wrote in message <6j774d$t97$3...@uni00nw.unity.ncsu.edu>...
Patrick Keenan
Yes, this is generally an excellent work (there's some bad suggestions in his
acoustic book as I recall - one of his methods of rosette construction cannot
work properly). I seem to recall that there is more than one edition; in the
early ones he included a variety of guitar schematics (extremely useful) and
some manufacturers took issue with this. However the issue may have been
royalties rather than disclosure.
-pk
Patrick F. Coleman wrote:
> Thurston <"<john_thrush"@ncsu.edu>> wrote:
>
> >> I have never seen Epoxy used successfully for this purpose. What it
> >> was successful at was making sure the pickup could never be fixed.
>
> >EMG uses epoxy and I think it works really well. Carvin also epoxy dips
> >their pickups. I believe Seymour Duncan also epoxy dips their active
> >pickups.
>
Patrick Keenan
EMG uses epoxy for another purpose, not to correct microphonics. It's not
unusual to see epoxy used to cover proprietary or easily duplicated
electronic circuitry, like the preamp used to convert the EMG coil output to
high impedance. Protecting market share and competition are the driving
force there. It's not a solution to a technical problem.
Epoxying a new, known non-microphonic pickup might keep it from eventually
becoming microphonic, but I'm not sure it's possible to tell. Epoxied or
not, it might never have become microphonic anyway.
Gobson also epoxied the pickups used in the L6-S line. Bad idea, or bad
implementation: we saw a fair number with the PU wires broken too close to
the epoxy surface to allow repairs. Only alternative was replacement.
Sachin Kandhari
NOCTURNAL10 wrote:
> Epoxy does more to ensure that the PU cannot be reverse engineered than
> anything,A hard wax works just as well.
>
Umm...newbie question.
What is the epoxy for?
Sachin
evil twin®
It's used to cover everything in a big gloppy mess so that curious
people can't inspect something to see how it works.
stevi...@hotmail.com
In article <355f1b86...@news.primary.net>,
More importantly, it repels beer, sweat, drool and Whopper juice.
BB Rob
-----== Posted via Deja News, The Leader in Internet Discussion ==-----
http://www.dejanews.com/ Now offering spam-free web-based newsreading
L'Entarteur
Well, since no one has answered your question seriously yet, I may as
well step up to the plate.
When a pickup goes microphonic, that means that the windings of wire
inside have come loose and started to vibrate, rather than simply
conducting the electrical field through the wire. This causes feedback
and whatnot, and can usually be proven by yelling or making noise into
the pickup--in a non-microphonic pickup, it shouldn't pick up outside
noise, in a microphonic one, you can practically talk through it like
...well, like a microphone, sometimes.
So you pot the thing in wax or epoxy, which holds the windings still, and
the pickup no longer acts like a microphone, but like a pickup.
Jas.
----------------------
James Andrews
Philadelphia, PA
Remove th eXX
evil twin®
On Thu, 14 May 1998 15:04:10 GMT, stevi...@hotmail.com wrote:
>In article <355f1b86...@news.primary.net>,
> ha...@primary.net wrote:
>>
>> On Wed, 13 May 1998 20:30:17 +0400, Sachin Kandhari
>> <sac...@emirates.net.ae> wrote:
>>
>> >Umm...newbie question.
>> >What is the epoxy for?
>>
>> It's used to cover everything in a big gloppy mess so that curious
>> people can't inspect something to see how it works.
>
>More importantly, it repels beer, sweat, drool and Whopper juice.
Wax does a better job and still allows it to be worked on.
stevi...@hotmail.com
In article <356a6cc1...@news.primary.net>,
Plus, in the event of a power failure, you can burn your pickups...
evil twin®
On Fri, 15 May 1998 20:32:11 GMT, stevi...@hotmail.com wrote:
>In article <356a6cc1...@news.primary.net>,
> ha...@primary.net wrote:
>>
>> On Thu, 14 May 1998 15:04:10 GMT, stevi...@hotmail.com wrote:
>>
>> >In article <355f1b86...@news.primary.net>,
>> > ha...@primary.net wrote:
>> >>
>> >> On Wed, 13 May 1998 20:30:17 +0400, Sachin Kandhari
>> >> <sac...@emirates.net.ae> wrote:
>> >>
>> >> >Umm...newbie question.
>> >> >What is the epoxy for?
>> >>
>> >> It's used to cover everything in a big gloppy mess so that curious
>> >> people can't inspect something to see how it works.
>> >
>> >More importantly, it repels beer, sweat, drool and Whopper juice.
>>
>> Wax does a better job and still allows it to be worked on.
>
>Plus, in the event of a power failure, you can burn your pickups...
Why burn pickups? That's what PRSi are for. Nothing burns better than
a flame maple 10 top.