Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

Coil tension and tone.....

1/8/2005 2:52 AM
Dave Stephens Coil tension and tone.....
This has only been briefly touched upon awhile back, and Josh and I were talking about this and I remember Andreas Kloppman saying that loose coils were bright with more output. that tight coils were darker sounding.  
After thinking about this it doesn't quite make sense. A tight coil is closer and smaller in size and tight up against magnets as in a strat coil. This would make it brighter and edgy sounding. A loose coil would be fatter and larger and presumably sound fatter and more mellow?  
I've never sat down and wound two coils with identical winds and tried both extremes and wonder what others experience in this area is.  
I have noticed that the only two vintage Fender single coils I have gotten hold of seemed to be wound kind of loose. You could push on the outside of the coil and it would flex under pressure. One from the 60s and one from the 70s.  
Comments, experiences???
1/8/2005 11:00 PM
Josh Pardes

Dave, sorry I didn't get back to you sooner, been busy the last couple of days but I was going to go ahead and look into that. One thing that I have found however with the tight coils is that the wire stretches a bit which will give a higher resistance reading. I wound a very tight strat pup to 7k and it was still very bright due to this.  
Has anyone ever measured the tension, (i.e. torque) that different guages of wire can take before stretching? If not I may have some work on my hands. It would be nice if more factors in the winding process could be quantified.
Book Of The Day The Ultimate Tone, Volume III by Kevin O'Connor
Have you ever wondered if there is a better way to build a Bassman, Champ, Plexi, an 800, AC-30, Bulldog or Portaflex? Or you wanted to build an SVT with off-the-shelf parts? How about a master-volume amp that doesn’t change tone with the master setting? Everything you need to know is right here, including: proper grounding techniques, wiring methods, and mechanical considerations. Eighteen chapters cover the “iconic” amps everyone knows and loves, with schematics and layouts for each, along with the technical history of the product. Eyelet-board and chassis-mounted tube socket construction is used throughout, for easy servicing and modding. TUT3 is very accessible even if you cannot fully read a schematic and is a "must have" if you are going to build an amp for your self.

Note: The Ampage Archive is an Amazon Associate site. A small commission is paid to the site owner on any qualified purchase made after clicking an associate link such as the one above.
1/9/2005 3:03 AM
Andrew C.
Your friendly wire manufacturer should have the specs on stretching - something like tension required to induce lengthwise distortion of 1%, 3% and 5%. I remember my elektrosola spec sheet had this info with my last order, but I can't locate it.  
Andrew C.
1/9/2005 3:33 AM
Dave Stephens
Josh: there are specs for grams of tension to use with different gauges of wire. Unfortunately tensioners that use a spring reading scale don't work with pickups as the spring gauge jerks around like a jackhammer because the coil is oblong and actually is jerking the wire every revolution. This also breaks the wire :-) I found that out after buying an Azonic tensioner. They work great on round coils. It did give me kind of a sense of what certain grams of tension feels like but I returned it. Felt tensioners work because they are dumb simple. You can actually tell when the wire is starting to stretch between the coil and the felt tensioner with experience, after awhile you just know when its about right. If you turn the face plate and the feed side of the felt tensioner doesn't show any wire moving then you are stretching the wire. Also you have to keep checking the tension on the felt because the wire wears a path and the tenions quickly gets loose as you wind, I have to check the damn thing 4-5 times duirng one coil.  
But back on topic still am curious that if you wanted to brighten up a coil would winding it pretty loose do that? Also, if you are using heavy build wire there is more insulation between winds so if loose coils make a pickup brighter then does heavy build insulation do the same thing to a minor degree. DAve
1/12/2005 4:03 AM
Part of the loosness generates a brighter tone thing may come from the fact that of two identically sized coils wound from the same wire, the looser coil would be brighter than the tight coil because it would have less winds than the tight coil. So, in the case of equal sized coils, you'd have loose with less winds vs tight with more winds.  
If you performed your experiment another way with unequal sized coils with the same number of winds, and tension being the only variable, you may get different results.  
Seems like I've read that looser coils are more microphonic somewhere, but not sure.  
I've thought about this stuff too, but have next to no experience since I've only wound about a 1/2 dozen pickups. While rewinding I did notice that it seems like some companies use the lead holes (not the holes with the eyelets, but the holes the insulated wires go through)in the bobbin as a stop point for winding the coil, and there was room for quite a bit more wire, so I drilled new holes further away from the center of the coil.
1/12/2005 8:46 AM
moocow Resistance is Futile!
Yes, fewer winds will have an audible effect because the pickup will have less inductance, which affects the frequency response. The pickup inductance interacts with the guitar volume/tone controls, guitar cable capacitance, and amplifier input load to create an EQ network. It turns out that more inductance causes more highs to be lost in this EQ circuit. This means the pickup is brighter because the pickup has less inductance, not because the wire has more tension. This also means that resistance 'specs' are misleading because the turns count is what really makes the pickup sound they way it does. Inductance itself is related to the square of the turns count so a small error in turns becomes a large error in inductance. By winding to a resistance value, you can't get the turns count right because you don't know what tension your competetors are using. But by winding to a specific turns count or inductance value, you stand a much better chance of winding a successful pickup.  
Contrary to internet rumor, DC resistance is far less important to the high-frequency response of a pickup than its inductance. An analysis of the EQ circuit shows that the resistance of the pickup has does not affect the high frequency response very much because the inductance dominates the pickup impedance at high frequencies. As a result, the resistance can be off the so-called resistance spec and there won't be an audible difference as long as the turns count and inductance are correct. There have been a number of posts here on Ampage from people who have wound to the 'correct' resistance but their pickup sounds harsh to them. The theory above fits well to their experience.  
Questions like these are why I'm so interested in seeing inductance measurements of pickups. You guys are making a lot of good guesses, but you can also be making some good measurements to back up what your ears are telling you. There are a lot of variables in making a pickup and I believe many of them are simply affecting the inductance of the pickup. If two pickups of similar design sound different but have a different inductance value, then there should be no mystery as to why they sound different. However, if the two pickups are wound to the same turns count and inductance value but still sound different, then you have something interesting to investigate!
1/12/2005 10:59 AM
DAnger Will Robinson this thread has veered off course :-) Back to the original question: if you have two coils IDENTICAL winds and you wind one loose, will it be BRIGHTER sounding? I don't have time to try this.  
I did just wind two identical coils, same resistance, but one with heavy build insulation. The heavy build insulation coil was noticably brighter. I'm thinking its because there's more capacitance going on since the actual metal in the wire has more gap between wires because its filled with hevier insulation. So if thats true then theoretically a looser coil would have the same effect. Capacitance if this is what causes this is something you can't really measure in a pickup if I understand this correctly from earlier discussions.  
Yes, I always measure inductance. Interestingly enough in this same coil, poly/nylon and heavy build wound to same resistance had the same inductance and plain enamel was noticably higher, don't ask me why.....voodoo I guess.......Dave
   Page 1 of 18 Next> Last Page>>