The reference thread for newbies!

[Biarnel]

Do both coils have the same DCR reading?

Y E S, and it's 1.8KOhm.

BTW, I've scoured the web for good bass pickup references as well. Doesn't seem to be much out there, everything is geared toward guitar...

Isn't it annoying??
This is why I made this thread. The world needs some bass PU specs in safe and clean space

[Biarnel]

I'm just guessing here but i'd say 7500 turns is a wee bit more than 1000 feet. The coil is screwed no matter how you slice it!

Ok, let's do the math together.
As I stated in another reply somewhere here, I have two small 2-strings coil, let's take them one at a time: a coil is approx 7cm of circumference; not more than that, because it's 2-strings, not 4.

7cm cf., 7500 turns, it's 52500cm, so it's 1722ft approx.
With a AWG42 the table says 1659Ohm per 1000ft.
My coil is 1800Ohm. More or less what that table says.

Am I doing well 'til now? I think I'm messing up something stupid.

Is that how you are wiring the 2 coils?? or parallel?? Parallel you divide right?

Series, of course. But with a 3.6K in series, it's still crap.

In a humbucker, say a PAF style you have approx 4500 to 5000 turns per coil, the whole thing should OHM out somewhere near 8 to 9K meaning each coil is somewhere around 4 to 4.5K .

Well, a PAF style PU has -much- longer circumference then mine.

If you know you are right why come here and ask any of us??? Then we try to tell you what is happening and you disagree. I say figure it out yourself!!

Calm down, I'm only here to learn something, and we are only experiencing some communication troubles.
I come in peace.

[madialex]

Y E S, and it's 1.8KOhm.



Isn't it annoying??
This is why I made this thread. The world needs some bass PU specs in safe and clean space

yes maybe i am taking you the wrong way, sorry for that. The fact remains that the DC reading is way too low for 7500 turns, period. 7500 turns is 7500 turns no matter what, your readings are way too low. It could be possible you are wiring them in parallel and just not seeing that you are doing it. Draw us a picture of how you are wiring them up together.


By the way, those are some sweet guitars you have there, the bass is awesome.

Are you putting the finish ends of the coils together, then using 1 start for the hot and the other for ground. Do that and tell me what reading you get.

[Biarnel]

So, this is my coil (actually, one of the split coil of the p-style):
- see attachment -

As you can see, the bobbin is pretty small. 7500 turns are 1722 feet, approx.
So I think that is too few. Even if I solder in series the two identical coils, I read 3.6KOhm and the sound is thin.

Remember, traditional p-bass PU have 10.000 turns per coil!

So,what's your opinion? Just add 2000 turns (the circumference will be way greater!) and I'll have the right resistence, punch and volume?

[Biarnel]

By the way, those are some sweet guitars you have there, the bass is awesome.

Thank you, I really appreciate that.
The website is a little outdated, those are most of my "younger years" works
The new products are something more... "mature".

Are you putting the finish ends of the coils together, then using 1 start for the hot and the other for ground. Do that and tell me what reading you get.

3.6Kohm
that is two 1.8k coils in series!
I started thinking you skipped some of my post here: the coil is small, and 7500 turns are only 1722feet.

[Dave Kerr]

You should be getting 2.857K per coil DCR by my math - significantly off from your reading. The fact that they're each consistent makes me curious as to whether it is indeed a short - that's a bit of a coincidence to have them short in the same way. Maybe a bug with your counter? Or the wire isn't really 42 AWG?

[DrStrangelove]

Thank you, I really appreciate that.
The website is a little outdated, those are most of my "younger years" works
The new products are something more... "mature".



3.6Kohm
that is two 1.8k coils in series!
I started thinking you skipped some of my post here: the coil is small, and 7500 turns are only 1722feet.

Hi, my rough estimations say the coil will be around 2800-3000 ohms.

What is the distance between the magnets?

Bobbin height: 16mm
Bobbin thickness: 10mm
Bobbin width: ??

-drh

[madialex]

So, this is my coil (actually, one of the split coil of the p-style):
- see attachment -

As you can see, the bobbin is pretty small. 7500 turns are 1722 feet, approx.
So I think that is too few. Even if I solder in series the two identical coils, I read 3.6KOhm and the sound is thin.

Remember, traditional p-bass PU have 10.000 turns per coil!

So,what's your opinion? Just add 2000 turns (the circumference will be way greater!) and I'll have the right resistence, punch and volume?

Hi, Actually if you look at the coil, look just above the left magnet, Looks to me like there is a frayed wire there and near the inside of the coil close to the left magnet it looks like a bunched up lot of wire there. May be my eyes are seeing things that aren't there? I'll have another look. But still 7500 turns is what a strat should have or there abouts, actually it is a lot more than a strat single coil has and most strats are 5.8 to over 6K some even 7K. I'm confused about the 7500 turns. Actually on a coil that small with only 2 magnets you shouldnt even be able to get 7500 turns of 42 wire on there.

Is it possible that your counter is putting a decimal in the wrong place and you are getting 750 turns. For that size coil for me to wind 7500 turns on there I would think I would need 43 or even 44 awg wire. Heck with a small coil like that you might be able to get 7500 turns.

Maybe try 43 wire and go with about 8500 or 9000 turns if you can do it. You should get a little more beef out of each of them and output. It looks like you could put quite a bit more wire on if you wanted to.

[madialex]

Heres what I have found for you to look at

This is a chart of some typical fender specs.
1954 to 1967 Fender Stratocaster Pickup Specs

Year Ohms Wire OD Insulation Turns WD MP Wound

1954 5.76k .0030" Formvar 7956 TL/TG North Hand
1955 5.89k .0029" Formvar 7844 TL/TG North Hand
1956 5.98k .0029" Formvar 8012 TL/TG North Hand
1957 6.02k .0029" Formvar 8105 TL/TG North Hand
1958 6.20k .0028" Formvar 8350 TL/TG North Hand
1959 5.95k .0030" Formvar 7925 TL/TG North Hand
1960 6.33k .0028" Formvar 8293 TL/TG South Hand
1961 6.19k .0029" Formvar 8119 TL/TG South Hand
1962 6.22k .0028" Formvar 8220 TL/TG South Hand
1963 6.37k .0028" Formvar 8319 TL/TG South Hand
1964 6.25k .0027" Formvar/Enamel 7980 TL/TG South Hand
January 4, 1965, CBS bought Fender Musical Instruments.
1965 5.80k .0026" Plain Enamel 7626 TL/TG South Machine
1966 5.76k .0026" Plain Enamel 7630 TL/TG South Machine
1967 5.88k .0027" Plain Enamel 7656 TL/TG South Machine
Year Ohms Wire OD Insulation Turns WD MP Wound

[GlennW]

Are you sure your turn counter is accurate?

[Biarnel]

Medialex, you keep talking about strat pickups, and guitar pickups

This is a bass pickup the flatwork is 2cm x 4cm, and there's plenty of room for 7500 turns.

Actually, I just winded 11500 turns of AWG42, just a little more than the typical P-bass pickup (which is 11000 per coil). Each coil is 3KOhm.

Now I'm going to install them in a precision clone and have a test.

...I think the main confusing thing here was the size of the mags and of the coil. It's not that small.

[Biarnel]

What is the distance between the magnets?

Bobbin height: 16mm
Bobbin thickness: 10mm
Bobbin width: ??

The mags are 10mm dia.
The center of the mags are 18mm far.

[madialex]

Medialex, you keep talking about strat pickups, and guitar pickups

This is a bass pickup the flatwork is 2cm x 4cm, and there's plenty of room for 7500 turns.

Actually, I just winded 11500 turns of AWG42, just a little more than the typical P-bass pickup (which is 11000 per coil). Each coil is 3KOhm.

Now I'm going to install them in a precision clone and have a test.

...I think the main confusing thing here was the size of the mags and of the coil. It's not that small.

Probably so. Now i'm really confused Oh well, hope it works out for ya. I am going to wind a smaller coil today just to see what I get, maybe then I'll understand what you are doing.....

[Biarnel]

Medialex, think to the size of mag poles in music man style bass pickups (stingray etc). I use THAT size. Now think to two of that poles. That's it.

I tried the PU on a chinese precision clone. Well, it's sweet.
Low on volume, maybe due to the low DCR (6KOhm), but clear, punchy, lots of harmonics. Beef and rough like a precision PU should be.
No hum at all.

With a K&K preamp and a bit of gain, it's BOOOM

Now, the next quest is:
A jazz style pickup, 4 string, dual coil (2 coils, 2 strings each, one next to the other, like |O O| |O O| )

Any magical recipe?
Keep in mind that I will use the 10mm dia. 15mm tall alnico V mags that I have, one per string.
(this will lead to a larger coil than the one obtained using 5mm dia. mags...)

[David Schwab]

Very nice page, Dave Kerr! It's on my bookmarks now.

Well, 7cm cf., 7500 turns, it's 52500cm, so it's 1722ft approx.
With a AWG42 the table says 1659Ohm per 1000ft.
My coil is 1800Ohm, so it's more or less correct. I think I have to give it MORE turns.

Anyway this means my coils don't have shorts
(and the fact that the ohmeter reads an open circuit testing le coil start and the mags confirm that)

Someone would suggest how many turns should I give to this coil?

No, it's NOT correct.

Let's say one wind around a P bass bobbin is about 5 inches (bobbin is 2 inches wide X2). 5 inches times 7500 turns is 37,500 inches. Divide that by 12 and we get 3,125 feet. Divide that by 1,000, and we get 3.125. Multiply that by 1659 (Ohms) and we get... 5,090.25 Ohms! 5K.

As I said, each coil in a P bass is about 5K. Go look up P bass pickup at Seymour Duncan. They are usually about 10-12K total.

So your coil is WAY too low.

How's this?
(a generic DiMarzio P clone)