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Interesting day of experiments

6/20/2004 8:57 AM
Andy C	Interesting day of experiments What a day! Decided it was time to do a little benchmarking, so I had my own mini-"shootout" at home, so I went out and bought one of the best selling California made premium pups on the market. I shall call this Retail Pickup X (RPX). The results - The RPX has more "growl" than the Andy C homegrown version wound to the same resistance, and the bass is about 20% louder and boomier (in a good way). The trebles were very similar but the RPX would have to be called "chimier". I was very disappointed by this. Decided to do a little reverse engineering and unwound the RPX, and noted that it was a) machine wound b) had no internal variation in the number of winds per layers -70 winds per layer all the way through. So I rewound my pup to copy the RPX as closely as possible (I still use a "digital" traverse system, in the tradition sense of the word) using all the Zen concentration available to me. This evened the playing field a little, but the bass was still 15% lower in volume and maybe 20% off in "growl"...closer, but no cigar...and the kind of difference that ANY player would notice. I only have some PU double build 42 at home, so I figure, OK - its the wire, when I get some Formvar we'd be pretty close, until I rewound the now empty RPX bobbin to the same specs (6.5k) Despite being handwound and using PU instead of Formvar, my rewind was virtually identical sounding the original! The bass was there, in all its glory, and chime was there in force. So the question that remained was - "If it ain't the wind, why the hell aren't my pups delivering?" Now I know pretty much that a) it ain't the wind (layering, tension, scatter etc.) b) it ain't the coil height c) it ain't the magnet dimensions d) it ain't my winder e) it ain't my wire THEREFORE it must be the magnets... The only way forward is to order some magnets from a difference source. I remember a thread a while back that asked "Is all Alnico created equal?" - and until I can think of another variable i haven't considered I am now of the opinion that sourcing the right magnets is just as important as spending sleepless night worried about turns/layer... I know Wolfe went through the learning curve on rewinds, but I always figured you only learn how to WIND by doing rewinds. Not so. Flames, comments, tales about formative learning experiences all welcome. Names of recommended "musical" magnet suppliers as oppose to "industrial" magnet suppliers also welcome.

6/20/2004 8:57 AM

Andy C

Interesting day of experiments

What a day! Decided it was time to do a little benchmarking, so I had my own mini-"shootout" at home, so I went out and bought one of the best selling California made premium pups on the market. I shall call this Retail Pickup X (RPX).

The results -
The RPX has more "growl" than the Andy C homegrown version wound to the same resistance, and the bass is about 20% louder and boomier (in a good way). The trebles were very similar but the RPX would have to be called "chimier". I was very disappointed by this.

Decided to do a little reverse engineering and unwound the RPX, and noted that it was a) machine wound b) had no internal variation in the number of winds per layers -70 winds per layer all the way through.

So I rewound my pup to copy the RPX as closely as possible (I still use a "digital" traverse system, in the tradition sense of the word) using all the Zen concentration available to me. This evened the playing field a little, but the bass was still 15% lower in volume and maybe 20% off in "growl"...closer, but no cigar...and the kind of difference that ANY player would notice.

I only have some PU double build 42 at home, so I figure, OK - its the wire, when I get some Formvar we'd be pretty close, until I rewound the now empty RPX bobbin to the same specs (6.5k)

Despite being handwound and using PU instead of Formvar, my rewind was virtually identical sounding the original! The bass was there, in all its glory, and chime was there in force. So the question that remained was - "If it ain't the wind, why the hell aren't my pups delivering?"

Now I know pretty much that
a) it ain't the wind (layering, tension, scatter etc.)
b) it ain't the coil height
c) it ain't the magnet dimensions
d) it ain't my winder
e) it ain't my wire

THEREFORE
it must be the magnets...

The only way forward is to order some magnets from a difference source. I remember a thread a while back that asked "Is all Alnico created equal?" - and until I can think of another variable i haven't considered I am now of the opinion that sourcing the right magnets is just as important as spending sleepless night worried about turns/layer...

I know Wolfe went through the learning curve on rewinds, but I always figured you only learn how to WIND by doing rewinds. Not so.

Flames, comments, tales about formative learning experiences all welcome. Names of recommended "musical" magnet suppliers as oppose to "industrial" magnet suppliers also welcome.

6/20/2004 10:30 AM
Sheldon Dingwall	Interesting post. What style of pickup are you doing comparisons on? It sounds like a P or a J.

6/20/2004 10:56 AM
Jason Lollar	"Is all Alnico created equal?" I found slight differences in my suppliers which I only use a few. Pre-charged magnets always seem to be about 15 or 20% lower than what they can actually hold.

6/20/2004 8:12 PM
Andy C.	Forgot to mention, its strat single neck/mid vintage stagger

6/21/2004 3:38 AM
Dave Stephens	I think I would suspect magnet STRENGTH from what you are saying. I noticed that my first pickups had the same lack of coolness. I made that guassmeter with Radio Shack parts and all the Fender pickups I measured were stronger magnets than what I was getting from my supplier. Get one of those neo magnets and charge your home grown pickups with it and see if it makes a difference. Also magnet heights DO make a difference so see if your magnets are the same height as the evil machine made pickup.....Dave

6/21/2004 3:38 AM

Dave Stephens

I think I would suspect magnet STRENGTH from what you are saying. I noticed that my first pickups had the same lack of coolness. I made that guassmeter with Radio Shack parts and all the Fender pickups I measured were stronger magnets than what I was getting from my supplier. Get one of those neo magnets and charge your home grown pickups with it and see if it makes a difference. Also magnet heights DO make a difference so see if your magnets are the same height as the evil machine made pickup.....Dave

6/21/2004 11:58 AM
Andy C	Called my magnet supplier (always fun because he doesn't speak English!) and he wants to see a sample of the RPX magnets and is happy to put them under the microscope to keep me a happy customer. He also said that there are many variables used in the creation of a family of magnets which are referred to as Alnico V. I was kind of under the impression that Alnico V was a standard formula, but I fear that is something that magnet companies put forward - they want their product to appear sturdy, standard, maximised etc., rather than being open about Alnico V's range. Possible solutions on the drawing board are: 1. Remagnetizing some existing Andy C coils in my suppliers magnetizer to see if they improve 2. Following Dave Stephens' advice and just doing this by hand with a charger bar. 3. Waiting for the results of materials test from my supplier to see if RPX is using a different formula. I'll probably end up doing all three of the above and report back. One thing that still bothers me though is that the volume and output drop was only VERY noticable on the bass strings.

6/21/2004 11:58 AM

Andy C

Called my magnet supplier (always fun because he doesn't speak English!) and he wants to see a sample of the RPX magnets and is happy to put them under the microscope to keep me a happy customer. He also said that there are many variables used in the creation of a family of magnets which are referred to as Alnico V. I was kind of under the impression that Alnico V was a standard formula, but I fear that is something that magnet companies put forward - they want their product to appear sturdy, standard, maximised etc., rather than being open about Alnico V's range.

Possible solutions on the drawing board are:
1. Remagnetizing some existing Andy C coils in my suppliers magnetizer to see if they improve
2. Following Dave Stephens' advice and just doing this by hand with a charger bar.
3. Waiting for the results of materials test from my supplier to see if RPX is using a different formula.

I'll probably end up doing all three of the above and report back.

One thing that still bothers me though is that the volume and output drop was only VERY noticable on the bass strings.

6/23/2004 11:34 AM
Andy	And, If you could look back a few months we discussed the variances of magnet strength. I was getting some spurious results and some strange comments from customers who'd previously been very happy with our pickups. Like you we went through a whole series of tests before we established that the mags must be at fault. We purchased a decent Gaussmeter and got back some of the "dodgy" pups on each three of the magnets had much lower readings than expected. We now meter all our magnets before assembly and use, in the case of strats, six magnets with similar strength. For humbuckers we have established a strength which suits us. Not all magnets, not even from the same supplier and produced in the same batch, are equal. A meter can help, as can storage. Andy

6/23/2004 11:34 AM

Andy

And,

If you could look back a few months we discussed the variances of magnet strength.

I was getting some spurious results and some strange comments from customers who'd previously been very happy with our pickups.

Like you we went through a whole series of tests before we established that the mags must be at fault.

We purchased a decent Gaussmeter and got back some of the "dodgy" pups on each three of the magnets had much lower readings than expected.

We now meter all our magnets before assembly and use, in the case of strats, six magnets with similar strength. For humbuckers we have established a strength which suits us.

Not all magnets, not even from the same supplier and produced in the same batch, are equal.

A meter can help, as can storage.

Andy

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