pickup resistance?

[Stevie Nazarenie]

what does pickup resistance actually mean? i was curious to measure some of my pups. the g400 epi neck was around 8k the bridge around 14k (thats hot!) my old gibson neck pickup is around 7k but it has more sustain than the epi bridge when i placed it in the bridge?

[carverman]

what does pickup resistance actually mean? i was curious to measure some of my pups. the g400 epi neck was around 8k the bridge around 14k (thats hot!) my old gibson neck pickup is around 7k but it has more sustain than the epi bridge when i placed it in the bridge?

 

This subject was well discussed a few weeks back. DC resistance is a function of

the number of turns of #42 awg copper wire around a bobbin or pair of bobbins' date='

if it happens to be a humbucker.

 

The number of turns of #42 wire is dependent on the supplier and batch of the

enameled copper wire on the roll that the pickup (or pickups) is being made from.

The dies used to make the wire will vary slightly in size (+/- 2 thousands of an inch)

depending on temperature and physical size of the die itself.

This has an effect on the size of the copper wire being formed and varies the

resistance (slightly) as there is a minimum dia; average dia, and

max diameter specification for #42 awg.

 

 

 

However, the dc resistance itself is not a direct function of the frequency response

of the p_up.

 

 

 

There are other factors as well:

 

a) the type of Alnico magnet... Type II and III being weaker in magnetic field strength

than type V (5).

 

The inductance of the coil(s) expressed in the electrical term :HENRIES.

The inductance of the coil at will have a certain resonance frequency and

this will vary from p_up to p_up

c) overwound vs underwound

 

d) the location of the p_up. At the neck the strings will vibrate more and are

lot more "mellower in tone" due to the various harmonic nodes picked up

at that area of the string(s).

On the bridge p_up the strings are tauter and the string vibration excursions

are not as wide, so the pickup has to be wound more (hotter) to produce

the same balanced output as at the neck position

 

Here's more from Seymour Duncan's Support/FAQ site:

 

[b']SD FAQ: 696.[/b] What determines the DC resistance of a coil?

The DC resistance of a coil is basically determined by the magnet wire gauge being used and the length or number of turns being used. As you increase the number of turns in a pickup, the DC resistance will increase. If the magnet wire is stretched when winding can cause the DC resistance to increase but if the magnet wire is stretched too far, it can cause the insulation to break and cause shorted turns that would lower the normal DC resistance. If a coil is wound too fast it can cause the wire to stretch and not give it enough time to form to the shape of the coil making the pickup spongy. Magnet wire is normally insulated and higher the number the finer or thinner the magnet wire. Winding two coils with 5,000 turns of 42 heavy insulation will have a higher DC resistance than a coil wound with 42 single insulation providing the copper conductors are both equal.

The 42 heavy insulation will cause the coil to be fatter and a longer length of magnet wire with increased DC resistance. Another important factor in determining the DC resistance is the temperature at which the magnet wire is being measured.

 

Also, the function of the magnet is to magnetize your strings in order for the field within

the coil to pick up the magnetized string's vibration, and that induces a weak signal

in the coil.

 

SD FAQ: 688. How does a guitar pickup work?

A magnet is normally permanently mounted inside a pickup and is used to magnetize the ferrous string. As the strings vibrate when being plucked an induced voltage and impedance is created that travels through the controls of desired specifications and amplified at the amp. The magnetic path is determined by the ferrous material or pole configuration, bobbin shape, magnet wire gauge, number of turns and the magnetic strength in proximity to the strings.

[GlennW]

The dies used to make the wire will vary slightly in size (+/- 2 thousands of an inch)

depending on temperature and physical size of the die itself.

This has an effect on the size of the copper wire being formed and varies the

resistance (slightly) as there is a minimum dia; average dia' date=' and

max diameter specification for #42 awg. [/quote']

 

Most pickups are made using 42, 43, or 44 awg wire. The stuff is skinny, so skinny there isn't room for .002" variation.

44 is about .002"

43 is about .00225"

42 is about .0025"

Wires of the same gauge with different types of insulation will vary in overall thickness, such as Formvar vs plain enamel. The difference in thickness will give a slightly different coil shape for the same amount of turns, and also produce a different tone.

 

What does pickup resistance actually mean? It means the one with the higher resistance has more wire, all other factors being equal. It'll likely have more output and have less highs. The higher numbers don't mean it'll sound better. The "hot" talk is mostly a marketing tactic...guys generally believe that more is better, but that's not always true.

 

The same pickup will give a higher reading when it's warmer. I've taken pickups from the mailbox (mini-oven) on a summer day that have read 10+K at first, but read around 9.5K after getting closer to room temperature.

[sjtalon]

I was doing a search for resistance and found this thread.

 

 

The question I ask on the above comment of "temperature effect".

 

To a persons ear, what would be the big deal of .5 K ???

 

BASICALLY, the resistance will effect the output (power) of the pup, so after they cool down from the mailbox, your amp will sound like you turned it down from 6 to 5 1/2.

 

 

Or is it when they're hot, they go to 11

 

Could be the reason for Ace's smoking guitar ??

 

Pup manufacturing is not EXACT winding wise. New pups can very per factory spec a hair up or down.

I'm not trying to be a wise guy, but if a "purest" where to sit down with a box of pickups and a meter to pick out the SUPER DUPER HOTTEST of the bunch (all other things being the same) how much difference would there have to be to make it a big deal??

[TWANG]

what does pickup resistance actually mean? i was curious to measure some of my pups. the g400 epi neck was around 8k the bridge around 14k (thats hot!) my old gibson neck pickup is around 7k but it has more sustain than the epi bridge when i placed it in the bridge?

 

carver and others posted well, I'll try to take different tack.

 

Vintage buckers are around 8K for gibsons..

hotter pickups will drive your preamp harder and give you earlier breakup..set them close to the strings and

they'll even distort a bit on their own.

neck pickups get more signal and need to either be balanced, less for neck, more for bridge, or kept farther from the

strings.

 

You'll just about always get more sustain at the neck, as the vibration toward the end of the string reduces more dramatically than at the middle.

the neck pickup is just sensing what is there.

 

A really good book and not expensive!, is donal brosnacs

Guitar Electronics , A Workbook

it contains scads of information, historys, wiring options, diagrams and schematics for guitars.. covering every kind and type with help from the manufacturers themselves.. rick gibson, duncan dimarzio armstong etc etc.

 

Very handy and useful!

 

TWANG