Does anyone make a HB with mismatched coils....

[Joey Voltage]

Re: Does anyone make a HB with mismatched coils....

You can't get 6k worth of 42 on a standard humbucker bobbin. Gotta be at least 42.5, probably 43. With the same number of turns -- or to be more precise, the same length of wire -- 42 will read roughly 25% higher, meaning a 6k coil of 43 is equivalent turn count-wise to about 4.7/4.8k. Which means, assuming the bigger coil is 43 and not 42.5, the turn count disparity between your Fred coils is not nearly as much as the DCR would otherwise suggest.

That’s the exact point. Under the 4501 patent, the turns count isn’t much different in order to maximize the CMRR, but the gauges of wire are in order to promote disparity in the resonat peaks of each coil. The only time dimarzio has appeared to break this rule and still hide the model under the 4501 patent is with the tone zone which I believe is 44awg in both coils.

 

[PicoRiveraTele]

Re: Does anyone make a HB with mismatched coils....

That’s the exact point. Under the 4501 patent, the turns count isn’t much different in order to maximize the CMRR, but the gauges of wire are in order to promote disparity in the resonat peaks of each coil. The only time dimarzio has appeared to break this rule and still hide the model under the 4501 patent is with the tone zone which I believe is 44awg in both coils.

You will not get different resonant peaks (at least not in the audible range) in each coil. The patent basically does little other than give DiMarzio exclusivity to a near meaningless technical distinction that can be exploited for marketing purposes.

 

[freefrog]

Re: Does anyone make a HB with mismatched coils....

That’s the exact point. Under the 4501 patent, the turns count isn’t much different in order to maximize the CMRR, but the gauges of wire are in order to promote disparity in the resonat peaks of each coil. The only time dimarzio has appeared to break this rule and still hide the model under the 4501 patent is with the tone zone which I believe is 44awg in both coils.

FWIW, I've measured dual resonant peaks on the coils of DiMarzio HB's... but also on other models of other brands, not supposed to concretize a dual resonance patent.

 

[gregory]

Re: Does anyone make a HB with mismatched coils....

I have a feeling Thanaton is back.

Who is this mythical Thanaton character that has all of you running scared, anyway?

It's like a knee-jerk reaction whenever someone asks for evidence or clarification in the face of religious voodoo.

Instead of rising to the occasion and helping future readers by answering the call, "veteran experts" (and non-veteran, self-professed "experts") often choose to resort to personal attacks.

EDIT #1: Added the quote freefrog edited away.

EDIT #2: I noticed you decided to say something more germane to the discussion rather than simply redacting your original Thanaton comment with "... ;-)". Much better. See, that wasn't so hard.

 

[Joey Voltage]

Re: Does anyone make a HB with mismatched coils....

You will not get different resonant peaks (at least not in the audible range) in each coil. The patent basically does little other than give DiMarzio exclusivity to a near meaningless technical distinction that can be exploited for marketing purposes.

A first approximation model of two series connected self generating coils with different inductance and a single parallel capacitance keeping in mind added cable capacitance will indeed show two distinct resonance frequencies. You can even reliably sim it out. How far apart they are is the determining factor. Sometimes they are close enough together that the peak is just wider in nature.

 

[PicoRiveraTele]

Re: Does anyone make a HB with mismatched coils....

A first approximation model of two series connected self generating coils with different inductance and a single parallel capacitance keeping in mind added cable capacitance will indeed show two distinct resonance frequencies. You can even reliably sim it out. How far apart they are is the determining factor. Sometimes they are close enough together that the peak is just wider in nature.

The inductances of the two coils sum to form a single inductance value that dominates the overall circuit, including the guitar cable and other stray capacitances. The self resonance of the coils that is caused by their isolation from one another is at a frequency that is higher than the dominant resonance of the two inductances combined. Since the amplitude drops off above the dominant resonance, which is of a lower frequency, those smaller, higher frequency resonances are never audibly realized.

 

[Mincer]

Re: Does anyone make a HB with mismatched coils....

Let's all calm down and get back to the OP, ok?

 

[gregory]

Re: Does anyone make a HB with mismatched coils....

I'm sorry if this is seen as out if order, but is there something wrong with discussing dual-resonant humbuckers from an engineering perspective?

EDIT: If this has to do with the Thanaton thing, I'll gladly delete my reply to the post that instigated it. I think the ad hominem attacks from forum members, especially in discussions where the attacking member hasn't previously participated, don't do well to bolster the reputation of this community, however.

 

[PicoRiveraTele]

Re: Does anyone make a HB with mismatched coils....

Here's an example I found showing a humbucker coil's self resonance as distinct from the overall resonance of the circuit:

You can see in the Hot Stack white plot line has one overall resonance that is very tall and dominant, and then a second resonance at a much higher frequency. In practice, that resonance will be buried beneath the noise floor and probably beyond the frequency response of the guitar amp's speakers. The Kinman Impersonator has a little blip where some sort of small second resonance occurs, and the two single coils show straight slopes. The self resonance is of a high frequency because the individual inductance and capacitance of a given coil is much smaller than that of the series inductance and lumped capacitance of the overall circuit.

So when DiMarzio mismatches coils, at best they're only playing with those small secondary peaks that are outside of the of the useful response range. It's probable that whoever filed for the patent wasn't aware of these finer points, and filed the patent based on a misunderstanding of circuit analysis, which the patent office granted, also due to a lack of understanding of circuit analysis.

 

[gregory]

Re: Does anyone make a HB with mismatched coils....

You know those are single-coil sized vertical stacks and not full-sized humbuckers per the original topic, right?

 

[PicoRiveraTele]

Re: Does anyone make a HB with mismatched coils....

You know those are single-coil sized vertical stacks and not full-sized side-by-side coil humbuckers, right?

Yes, the same phenomena occurs in both cases. A stack is (usually) wired in series like a regular humbucker, the only real difference is the physical orientation of the coils.

 

[Teleplayer]

Re: Does anyone make a HB with mismatched coils....

Maybe a dual resonance pickup such as Fred will have lower Q at resonance due to the interaction between the coils.

The PAF PRO may have some aspect of asymmetric winding because the Inside coil is 4.5k and the Bridge coil is about 0.2k less resistance. My example is like this.

 

[Mincer]

Re: Does anyone make a HB with mismatched coils....

I'm sorry if this is seen as out if order, but is there something wrong with discussing dual-resonant humbuckers from an engineering perspective?

EDIT: If this has to do with the Thanaton thing, I'll gladly delete my reply to the post that instigated it. I think the ad hominem attacks from forum members, especially in discussions where the attacking member hasn't previously participated, don't do well to bolster the reputation of this community, however.

I am all for everyone having great discussions on the minute details of all things guitar electronics. I also don't mind different perspectives on things. My big thing is that I want this place to be a resource for accurate info, so anyone researching these sort of things can find the answers among our posts. Attacks on anyone, from anyone here to anyone else on here isn't what we want, though. Even if their information is wrong- there is a better way to say that. I certainly am not singling anyone out here, I just want to keep it on topic.

 

[gregory]

Re: Does anyone make a HB with mismatched coils....

The PAF PRO may have some aspect of asymmetric winding because the Inside coil is 4.5k and the Bridge coil is about 0.2k less resistance.

The one I have collecting dust measures 4.45 and 4.27.

Unlike the TZ, the product page for the PP doesn't indicate it being under a patent, FWIW.

 

[freefrog]

Re: Does anyone make a HB with mismatched coils....

EDIT: If this has to do with the Thanaton thing, I'll gladly delete my reply to the post that instigated it. I think the ad hominem attacks from forum members, especially in discussions where the attacking member hasn't previously participated, don't do well to bolster the reputation of this community, however.

I was way too busy to read successive edits and I’d prefer not to enter in polemical relations that I disapprove.

But I’m honestly perplexed. What are you talking about?

You quote freefrog saying “I have a feeling Thanaton is back”.

This sentence has never been written by freefrog as such, according to your notes:

EDIT #1: Added the quote freefrog edited away.

It neglects the fact that it has been edited because it was not supposed to stay.

Now, even if the frog had said exactly the words attributed to me with an intention to leave them above (which is not the case)…

Since when is it an attack “ad hominem” to say that that an avatar with a fictitious name is “back"?

Especially when a new Star Wars has just been released here... http://starwars.wikia.com/wiki/Darth_Thanaton

In this topic, actually, it was a “tongue in cheek” wink referring to distant verbal echoes. Reason why it was not meant to stay and has quickly been replaced by a wink.

It would have been edited without your replies.

But if this wink had been done to test the reactions of other members, some replies would speak for themselves.

Oh, and FWIW, I had already contributed to this topic: see the answer 11.

All my other answers on this forum are there to show if freefrog is or not a trouble maker practicing personal attacks.

To compare if needed with posts from other members who don’t appear to do what they recommend to others.

Mincer, I hope to see this off topic stopping here.

 

[freefrog]

Re: Does anyone make a HB with mismatched coils....

Here's an example I found showing a humbucker coil's self resonance as distinct from the overall resonance of the circuit:

As this pic comes from me, I’ll add a minimalist comment.

This screenshot was a snippet illustrating non finalized experimental results, surely picked somewhere in my archived data and posted to answer in a defined context (I don’t even remember in which topic nor when).

If I had to use again this screenshot, I’d rather put it a topic about SC sized stacks. The measurements done here about HB’s are different, especially those involving dual resonance DiMarzio’s.

Also and FWIW: a minor mod on the Kinman mentioned in my picture would suffice to give it a distinct dual resonant peak, absolutely audible in a played guitar. This mod (involving only stock parts with no added components) has already been tried here.

So, even if I understand what you say and find it logical, my experience is more on par with what JoeyVoltage says.

 

[PicoRiveraTele]

Re: Does anyone make a HB with mismatched coils....

Maybe a dual resonance pickup such as Fred will have lower Q at resonance due to the interaction between the coils.

Interactions between the coils doesn't lower the Q (unless you split the humbucker, but that's another story), and that's the case regardless of whether the coils are matched or not.

Keep in mind that DiMarzio's patent stipulates that both coils have the same numbers of turns per coil, but different wire gauges, so they coils are not effectively mismatched at all. Because both coils have the same number of turns, they will have similar inductances and produce near identical voltage output. In fact, a regular P.A.F. having one coil with slugs, and one with screws, constitutes a greater coil mismatch than simply having used two different wire gauges. The difference you get from using thinner wire for one coil represents a trivial amount of series resistance, which you can measure yourself, and is the same as if you had put a 1k ohm resistor in series with one of the coils of a regular P.A.F. type pickup.

The PAF PRO may have some aspect of asymmetric winding because the Inside coil is 4.5k and the Bridge coil is about 0.2k less resistance. My example is like this.

That's a rather small difference in DC resistance. They could have identical turn counts per coil and you might still see that amount of difference in DC resistance.

 

[gregory]

Re: Does anyone make a HB with mismatched coils....

But I’m honestly perplexed. What are you talking about?

Thanaton was apparently a banned member who is suspected of coming back to troll this forum. I have been accused of being him on more than one occasion, hence my apparent misinterpretation of your initial post. I apologize for not getting the exact quote of what you said right, and I also apologize for the misinterpretation of your post.

My disenchantment regarding personal attacks against both me and others was not directed specifically at you, however. I regret that it appeared that way to you. I did however feel like you had decided to dismiss information based solely on the person saying it, though I don't know who you meant exactly. It is clear that that was not your intention and for that I once again offer my apologies.

 

[freefrog]

Re: Does anyone make a HB with mismatched coils....

I respectfully thank you for your courtesy.

I understand that sense of humor is something personal, especially with "tongue in cheek" crypted posts.

So, my own words are necessarily 50% responsible of a possible mutual misunderstanding.

Case closed for me. Have a nice day.

 

[PicoRiveraTele]

Re: Does anyone make a HB with mismatched coils....

As this pic comes from me, I’ll add a minimalist comment.

This screenshot was a snippet illustrating non finalized experimental results, surely picked somewhere in my archived data and posted to answer in a defined context (I don’t even remember in which topic nor when).

Thanks for creating that plot, it served the purpose well. I recall Scott Lawing made an observation that explains why the Hot Stack has a higher second peak, it's because of the added capacitance that sits in between the two coils in the circuit, by virtue of the shielded four conductor cable it comes equipped with. The connection between the two coils makes a run and back through that four conductor cable, capacitively coupling with the shielded cable along the way. The Kinman Impersonator, I presume, has a standard two conductor cable, and so it does not exhibit nearly as strong of a secondary resonance.

The interesting thing about that too, is that if you really want a pickup with two distinct resonances, the way you do it is not by pairing unequal coils in series, you do it by putting a capacitor to ground, in between the two coils. You take what that four conductor cable does, and just take it an extreme where it does become audible. The value of the capacitance needs to be rather high though in order to bring that second resonance down into the audible range, and by high I mean 1 to 10 nanofarads. Not a lot, but greatly in excess of the parasitic capacitance of four conductor cable. It's actually a very easy mode to do one's self, where you would normally "split" a humbucker, you put a 1nF to 10nF cap in series with the split switch. That will give a true "dual resonance", and it sound's sort of of "scooped" because there will be a corresponding valley, or band stop, in between the two peaks, with the exact tone you get being dependent on the cap value you choose to use. Anyhow, DiMarzio's dual resonance pickups don't resemble this circuit topology, and so unless they've buried a capacitor somewhere under the cloth tape, they're just ordinary pickups.