Anyone here ever wind their own inductors?

[idahodewitt]

I am always looking to save a few bucks, so I'm considering to take a stab at winding my own inductors instead of purchasing a finished product. Has anyone here done that? Just wondering if its worth the effort.

I was looking at using 10 gauge enameled motor winding wire. Looks as if I may be able to save around $180 on just my two woofer inductors over buying a finished product. I haven't found a formula (that I can understand) that calculates the amount of windings it takes to reach a specific mH value. (I'm challenged in the advanced math arena.) Is there another way to do this or could someone explain the math in simpler terms?

Question.....Could I use a meter that measures mH and with needle pointed probes just pierce through the skin of the wire and measure from the inner end of the coil to the proposed end of coil. The remaining coil of wire I'm feeding off of should not affect the readings should it?

I have alot of other inductors I could wind for other speaker crossover upgrades, so I'd like to be able to figure out how to do this. I'm trying to see if its feasible to try this or just pay for the someone else's finished product. Its just doesn't seem right to pay as much for four inductors as I'd paid for my KLF-20s.

[SET12]

Larry,

Unfornately there is more involved in wrapping your own.

One is a good accurate meter.

Two is how you do it!

When I was going to school, a few of my instructors chastised me for buying the North Creeks but on the North Creek site there was some obvious reasons why I thought I shouldn't as even the schools Inductance meter was not calibrated close enough.

And I thought it sounded a little messy, so I bite the bullet to speak of, and I have no remorse for doing it!

From North Creek

Is "Perfect Lay' better than "Scramble Wound"?

This is very dependent on the manufacturing process. Perfect Lay
uses slightly less wire than Scramble Wound, resulting in slightly
lower DCR. However, Scramble Wound inductors have slightly less
self-capacitance, which some individuals claim is audible. But there is
a caveat - perfect lay inductors that are wrap-and-dip (not
vacuum-impregnated) have mechanical resonance problems because the
inner windings do not get bonded. Scramble Wound wrap-and-dip inductors
do not have this problem because of the increased penetration depth of
the bonding fluid.

In our subjective tests, no one has been able to hear the difference
between a vacuum-impregnated Perfect Lay and vacuum-impregnated
Scramble Wound.

Are bobbin-wound inductors any good?

Bobbin wound inductors are usually scramble wound under high
tension inside a nylon bobbin, then taped with masking tape so the
outer wrap does not come loose, and are the least costly type of air
core inductor to produce. This is called "bobbin-wound, wrap-and-tape".
They suffer from high tension microfractures, severe high mechanical
resonance problems and also tend to be microphonic - not a good
combination inside a loudspeaker cabinet. Luckily, most bobbin-wound
inductors can be upgraded, by carefully removing the tape, applying a
bead of hot melt to fix the last outer wrap, then dropping the entire
inductor sideways in a can of clear shellac that has been thinned at
least 50% with alcohol and letting it sit for two or three days,
rotating the inductor every day, then allowing them to drip-dry
overnight. Because they are usually scramble wound, and thinned shellac
has very low viscosity, the penetration depth is quite high. Again,
there is a caveat - shellac is very brittle, and dropping a
shellac-dipped inductor will usually break its bond. If this occurs,
repeat the dipping process.

What about "goop-wound"?

Goop-winding is the process of winding an inductor inside a
bobbin or former, while a bonding agent (usually hot melt adhesive) is
applied directly to all of the windings throughout the entire process.
Goop-winding makes a very unattractive inductor, but they sound
remarkably good. This is the only method recommended for those that
wish to "wind their own".

And then we have the Micro Fractures to deal with.

From North Creek again!

First and foremost, our wire wound inductors are made on a custom
built, tension-free winding machine. This winding method minimizes the
stretch and mechanical deformation of the copper, so there is no strain
on the copper and its conductivity remains at a maximum. All copper
foil inductors (and most copper wire inductors) are wound at very high
tensions, so both the copper and the insulating film are stretched and
remain under tension for the life of the product. Tension is
differential stretch, which creates microfractures in both the copper
and insulating material. This is about the worst thing one can do to a
conductor.

The second factor is mechanical stability: North Creek inductors are
varnish sealed in a vacuum chamber, which bonds each winding to the six
surrounding it throughout the entire body of the coil. Most copper wire
inductors are varnish dipped, which seals the outer wraps but not the
coil body. Copper foil inductors are usually heat sealed, which seals
the edges but not the body. Typical copper wire and copper foil
inductors will have a number of mechanical resonances that are
activated by current flowing through the inductor, and can be heard to
"sing along" with the input signal. Because of their unique vacuum
impregnation, North Creek inductors do not show any signs of mechanical
resonance.

That's hard to compete with IMO!

I prefer the peace of mind that they are matched and the materials are correct not stretched and fractured! And so on! And when I'm spending the kind of money on Duelund caps that I have I'm even more glad that I made the purchase!

And while ALK proved that the "Q" factor of the North Creek weren't as good as say Solen Litz, for Bob Crites Titanium tweeters it wasn't even a contest in my listening experience, for me the North Creek was "oh so sweet and full sounding!" I for one never expected such a huge difference it was as though Bob's tweeters were a high power magnifying glass and everything became abrasive sounding it's as thought the Litz was to much!

So this is what I refer to as voicing and perhaps the Litz would work with something else better but not in my system and of course I use tubes and I can't imagine what SS would of been like can you say chalk board!

Cheers!

SET12

[Guest David H]

I was looking at using 10 gauge enameled motor winding wire. Looks as if I may be able to save around $180 on just my two woofer inductors over buying a finished product.

What inductors do you need? What crossover frequency ?

I have wound my own, and do not recomend it.

[idahodewitt]

The two values are 1.6mH and .16mH for the KLF-20. The crossover frequencies are 750 Hz and 7 kHz.

Since you have tried it, why would you not recommend doing it?

[Guest David H]

Since you have tried it, why would you not recommend doing it?

First, as stated before you will need tools to test the inductors afer you are done winding them. Second, it is difficult to wind the coils exactly.

Most of all because inductors are fairly inexpensive, and for your application I would use a quality Iron core for your 1.6mH like a super Q inductor from parts express and a aug14 foil inductor for the HF. If the values you are looking for are not readily avaialable, you have the option of picking something close, or go to the next value higher and retuning. The parts express woofer tester will check inductance, and can be used to retune a choke.

I saw you were considering AUG 10 for your inductor, but using an Iron core at 700 Hz will most likely give you a equal or lower dcr considering the wire will be 1/4 the length, and the Super Q inductors are good to 2khz or better.

Enjoy, Dave.

[tigerwoodKhorns]

This sounds like a huge pain for not much upside, and I am a huge DIY person.

You must need a lot of inductors, because I have always used Solen's and they are not very expensive at all, even their air core Litz inductors.

Double check your numbers. You can usually save money where very skilled and deyailed labor is needed, but mass produced products are hard to make cheaper yourself.

There is also a very old thread by Al K. when he was designing the ALK crossovers. He wound some inductors and tested several and found the Solen's to be the winner. I think it is the "Inductor Shooot"

[Don Richard]

Winding the coils is the easy part, but it ain't easy at all. The hard part is calculating the inductor parameters, which include wire size, ID, OD, coil length, and number of layers.

If you wish to do this empirically, the "cut and try"( literally) method will be necessary. The wire left on the end going to the spool of wire will affect the inductance reading, but I'm not sure by how much on an inductor operating at audio frequencies. If you are going to try this, wind the coil to be of a greater inductance than desired, then cut off a turn or two at a time until the desired value, as read on an inductance meter, is reached.

There are nomographs for winding coils for radio frequencies in my literature, but I could not find any for the audio frequency range.

It may be simpler and faster just to buy what you want, unless you want the learning experience from DIY.

Good luck!

[idahodewitt]

There is an inductor calculator which should get me close (wire lengthwise) to where I need to wind an inductor, then I could just overwind it a few turns and cut the wire, then measure back (unwind) to the desired mH reading if I have overshot it. The calculator is at: www.diyaudioandvideo.com/Calculator/Inductor/ . This calculator should do the trick shouldn't it? I'm good at building/designing things so it should not be a problem to build a precise jig to wind these on. I've developed an attention to detail from the years I'd spent in gemcutting (as a hobby) and 20+ years assembling, maintaining, and working with machinery. My electrical background is not one of much depth, so I appreciate everyones input so that I can make an educated decision on what to do that saves me time and/or money.

Also, thanks to the forum member that sent this website to me. I Googled 'winding inductors, parameters, specifications, etc,etc' and could not find it. That was what I was searching for. You saved me additional hours of searching. This forum is great!

[SET12]

Larry,

I just measured my North Creek 3mh 8 AWG and as close as I can measure them they sure are massive.

Diameter 6.5 inches

Height 1.5 inches

Inside Diameter of Hole 1.5 inches

DCR .10

The .16mh 8 AWG

Diameter 3 inches

Height 1.5 inches

Inside Diameter of Hole 1.5 inches

DCR .02

SET12

[SET12]

Since you have tried it, why would you not recommend doing it?

First, as stated before you will need tools to test the inductors afer you are done winding them. Second, it is difficult to wind the coils exactly.

Most of all because inductors are fairly inexpensive, and for your application I would use a quality Iron core for your 1.6mH like a super Q inductor from parts express and a aug14 foil inductor for the HF. If the values you are looking for are not readily avaialable, you have the option of picking something close, or go to the next value higher and retuning. The parts express woofer tester will check inductance, and can be used to retune a choke.

I saw you were considering AUG 10 for your inductor, but using an Iron core at 700 Hz will most likely give you a equal or lower dcr considering the wire will be 1/4 the length, and the Super Q inductors are good to 2khz or better.

Enjoy, Dave.

Unfortunately Iron Cores sound compressed in contrast to Air Cores due to "hysteresis distortion"

DeanG in ALK's Inductor shoot out thread mentioned a listening test he did with a Super Q Inductor that had the same DCR as his Solen 10 AWG Air Core's and as he said it was imediately obvious to him that the Iron Core sounded lean!

http://forums.klipsch.com/forums/t/38976.aspx?PageIndex=1

Perhaps some people can live with a lean sounding Inductor but I sure can't and certainly not after experiancing my 8 AWG monsters, routinely I get asked where's your sub!

SET12

[Guest David H]

Unfortunately Iron Cores sound compressed in contrast to Air Cores due to "hysteresis distortion"

DeanG in ALK's Inductor shoot out thread mentioned a listening test he did with a Super Q Inductor that had the same DCR as his Solen 10 AWG Air Core's and as he said it was imediately obvious to him that the Iron Core sounded lean!

http://forums.klipsch.com/forums/t/38976.aspx?PageIndex=1

Perhaps some people can live with a lean sounding Inductor but I sure can't and certainly not after experiancing my 8 AWG monsters, routinely I get asked where's your sub!

SET12

I agree that there are better inductors on the market than the Super Q, but I thought it would work well for the KLF-20, and is a good step up from the originals crossover components.

The best crossover is no crossover at all, and rather than spend mega bucks on overpriced capacitors and inductors you might consider going with an good active setup.

[idahodewitt]

A single 1.6mH inductor using 10AWG will almost take 100ft of wire.....whoa! That's a lot of wire! I may shop around for a really good price on the 10 gauge before I'd try winding my own. There are a few decent deals on eBay, but I'll keep checking around to see where I can find the best price. 8 AWG is hard to find and may be a bit too heavy to wind without the proper machinery. I have till the end of the month to buy some things from partsconnexion at a discount, but I can wait on the inductors as I gather information on this subject of winding them for a while longer.

[idahodewitt]

Dave,

I know nothing about an active crossover. They're definitely less expensive than rebuilding the stock x-over with high quality parts, but does ALL the sound get through without being distorted/diminished in any way?

[Guest David H]

The active crossovers are reasonably priced, but requires 3 amplifiers as well, so depending on the amps, actives can get expensive as well. In my opinion actives sound excellent.

The use of an active crossover eliminates the passive in-box crossover altogether, threrefore the only resistive element between the speaker and amplifier is the wiring.

Active crosovers are not for everybody, just another option.

[DrWho]

I wind my own inductors all the time....talk about saving loads of money.

I wouldn't recommend it though without ways to measure what you're doing. I actually never measure the actual inductance...I do the windings based off calculators and then throw it in the speaker and then tweak from there (always start with too many because it's easier to unwind).

[SET12]

Unfortunately Iron Cores sound compressed in contrast to Air Cores due to "hysteresis distortion"

DeanG in ALK's Inductor shoot out thread mentioned a listening test he did with a Super Q Inductor that had the same DCR as his Solen 10 AWG Air Core's and as he said it was imediately obvious to him that the Iron Core sounded lean!

http://forums.klipsch.com/forums/t/38976.aspx?PageIndex=1

Perhaps some people can live with a lean sounding Inductor but I sure can't and certainly not after experiancing my 8 AWG monsters, routinely I get asked where's your sub!

SET12

I agree that there are better inductors on the market than the Super Q, but I thought it would work well for the KLF-20, and is a good step up from the originals crossover components.

The best crossover is no crossover at all, and rather than spend mega bucks on overpriced capacitors and inductors you might consider going with an good active setup.

GotHover,

Thank you for your understanding of that!

And at the same time please pardon me, As my pursuit of performance is not something that is average but that of the extraordinary.

As I have found in my 35yrs of experience that "if one wants extraordinary sound one must do extraordinary things"

This goes for the rest of the system as well. And just doing what I did with my outboard networks doesn't guarantee the level of satisfaction that I get out of my system.

So ones mileage may vary a great deal.

But at the same token a project like I have done will allow the rest of ones system to express itself fully. Weak links are expressed as such as well.

In my system every part changed in my crossover was heard very easily. So what works is largely system dependent on a whole.

Though I have found that parts like the very large North Creek Inductors and Duelund Caps and Resistors make such a project more likely to succeed and succeed they do!

I to have experimented with outboard electronic crossovers.

But I found a better approach IMO. I would prefer to do it within my amplifiers! I saw this once in Sound Practices Magazine and I thought it was a stroke of genius!

Why you may ask!

Simply the elimination of gain stages!

Every gain stage you have in series is a form of compression and another loss of transparency. I often hear it in amplifier comparisons in watt for watt

If one is using solid state amplification like a many typical power amps you could easily have 5-7 ore more stages.

And if your using a line stage you can add those as well.

My power amps basically have just two gain stages. And a supply that has the equivalent energy of 10 typical home AV recievers.

And I don't use a line stage simply because they often get in the way. And the ones that I might be able to live with are in the 5-$10,000 range which I don't have.

Even my CDP is a real monster at nearly 40lbs and a power supply of 150,000uf's nearly 10 times that of an average CDP.

From what Larry was indicating to me it was my understanding that he wanted to pursue some of this especially when he is considering parts like the Duelund VSF Capacitors that I use in my networks.

Through the yrs a lot of money was spent and I had some pretty nice gear. But I can tell you nothing has ever been more thrilling than DIYing as I have with this stuff!

Doing what I did to my networks has taken me on a journey few people have gone before and I might add an extraordinary one at that!

Mine is but one journey and certainly nothing is written in stone!

And so everyone has the right to their own journey, and so, to each their own!

Cheers

SET12

[DrWho]

I to have experimented with outboard electronic crossovers.

But I found a better approach IMO. I would prefer to do it within my amplifiers! I saw this once in Sound Practices Magazine and I thought it was a stroke of genius!

Why you may ask!

Simply the elimination of gain stages!

Every gain stage you have in series is a form of compression and another loss of transparency. I often hear it in amplifier comparisons in watt for watt

I agree with the premise, but the actual implementation doesn't always come out as intended when going that route. Coupling more behavior into a single gain stage can introduce other compromises that may offset the desired increase in transparency.

[idahodewitt]

As I said before, I think I may just improve upon the existing crossover and keep it simple for now by putting together an 3-way outboard using the same values of caps & coils used in the stock x-over, but using better quality parts, some of which I'd have to wait a short while to afford. I may try an active crossover later on, but for now I'm just wanting to get the best sound out of a single low powered tube amplifier. Right now I'm running a single ended Magnavox 6BQ5 amp, AES AE-3 preamp w/Tung-Sol roundplate 6SN7, and an Arcam CD192 player. I have about a dozen other tube amps boxed up in my garage that I haven't tried yet, almost all of which need a recap, so I am not in need of things to do at the moment, even though I'm intrigued with making my own inductors.

The inductor winding seems simple to me, but I wanted some input from experienced people here in this forum so that I do not waste my time or money, especially the time since it is irreplaceable.....I can always get more money, but not more time. I have an idea to build an inductor winder with the wire ties built in so that I can cinch the coils up once they're fully wound. I also plan to seal the layers together with silicone as I wind them so as to eliminate any chance of looseness & vibration. This would be a fun winter project, along with all my other projects. If I can't find the time to build my winder, then its 'hello NorthCreek, send me some of those circular coily copper things that you make". I know what a 'night & day' difference it made when I upgraded the parts in a pair of Klipsch Tangent 500 crossovers. I can only imagine how much better the already very good sounding KLF-20s will be.

[Guest David H]

Here is a link to an inductor calculator. http://www.diyaudioandvideo.com/Calculator/Inductor/

Do some experimenting in here to find low DCR, for instance with a 2 inch diameter and 1 inch length the DCR is .11 ohms using AWG 10

Here is 350 feet of AWG #10 for around $100 http://cgi.ebay.com/ESSEX-Magnet-Wire-10-AWG-11-LB-Spool_W0QQitemZ370281296136QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item56367c3108

[SET12]

I to have experimented with outboard electronic crossovers.

But I found a better approach IMO. I would prefer to do it within my amplifiers! I saw this once in Sound Practices Magazine and I thought it was a stroke of genius!

Why you may ask!

Simply the elimination of gain stages!

Every gain stage you have in series is a form of compression and another loss of transparency. I often hear it in amplifier comparisons in watt for watt

I agree with the premise, but the actual implementation doesn't always come out as intended when going that route. Coupling more behavior into a single gain stage can introduce other compromises that may offset the desired increase in transparency.

Thank you DrWho,

Your key word "implementation" is correct. I use a a bottlehead C4S current source for my drivers plate load and LED biasing of the drivers cathode which makes for one dynamic driver stage. Gain of my output stage 811-10 or the 572-10 is typically twice that of a 300B. My power supply is also a contributor as well with an extremely low DCR path with a unique implementation of supply caps making for an extremely transparent fast and powerful amplifier.

But never the less when implemented well it is more often than not a more musical experiance IMO.

SET12