Dimarzio ,Humbucker from Hell ?

[copperheadroads]

Whats the deal with this pickup ? low output 5+k

[Helmholtz]

Whats the deal with this pickup ? low output 5+k

Resistance is not output. It is advertised as a brighter (not louder) alternative to a standard PAF, recommended for neck position.

[mozz]

Maybe it's wound with 41 or 41.5 awg?

[big_teee]

https://music-electronics-forum.com/...0&d=1368392741
Page 3 show's the Hummer from Hell frequency response.
It's big on Treble.
T

[Antigua]

Whats the deal with this pickup ? low output 5+k

This is the info I gathered from one I have on hand

DiMarzio Humbucker From Hell DP156BC

Series resistance: 5.96k ohms
green & white: 2.507k ohms
black & red: 3.432k ohms

Series inductance: 2.272H
green & white: 0.988H
black & red: 1.029H

Gauss at 3rd and 4th screws: 350-450G, AlNiCo 5

Unloaded: f: 11.5kHz (black)
green & white: f: 14.1kHz (green)
black & red: f: 13.8kHz (gray)
Loaded (200k & 470pF): f: 4.57kHz (red)




It's like Filter'tron electrical values in a PAF foot print. Less inductance and a higher resonant peak than a typical Strat single coil. The two coils have different DC resistances, but nearly the same inductance, suggesting the turn counts are about the same, but making use of different gauges of wire.

It's nearly the same as thre EJ Custom bridge pickup, except that the HFH has hex screws while the EJ's have standard screws and slugs.

[copperheadroads]

lol .........As if I didn't wind a 1000 pickups ............Just curious without doing a bunch of research ......First thing i thought would be to use bigger wire which i have ......

[Helmholtz]

Do you have an explanation for the depression below the res. peak in the frequency response? It looks like an eddy current effect.

[Antigua]

Do you have an explanation for the depression below the res. peak in the frequency response? It looks like an eddy current effect.

I don't know exactly the cause, but it's related to coupling with the adjacent coil, because if I remove that other coil from the pickup housing, a different plot emerges with a single resonant peak, with a frequency that is in between the two peaks. The other coil was open when I made the plot. In a tapped context, the coil would be shorted and the plot comes out a little differently. This relates similarly to the coil tapping discussion, where the primary seems to "borrow" attributes from the disconnected secondary.



As for why the green and white coil does this but not the red and black, I'm not sure, but the green and white uses a thicker gauge of wire, and so the coil is physically wider, 15mm versus 13mm, for the red and black coil. The thinner wire also means the red and black coil has a higher series resistance. I've seen this happen with other humbuckers that used mismatched wire gauges, so if you can offer any insight as to why this happens, that would be great.

[Helmholtz]

Thanks.
I agree that the double peak must be a coupling effect (Zollner found the coupling factor in standard humbuckers to be around 20%).

But I actually referred to the wide range depression between 1kHz and 8kHz. Well I see it's only around -1dB, but still... Doesn't this look similar to eddy current effects? (Admittedly not really significant).

[Antigua]

Thanks.
I agree that the double peak must be a coupling effect (Zollner found the coupling factor in standard humbuckers to be around 20%).

But I actually referred to the wide range depression between 1kHz and 8kHz. Well I see it's only around -1dB, but still... Doesn't this look similar to eddy current effects? (Admittedly not really significant).

I'm not sure about that. One interesting thing though is that if you short the secondary, as is the case in situ, you will see that dip very pronounced, as though it were (is?) a major cause of eddy current.

[Helmholtz]

One interesting thing though is that if you short the secondary, as is the case in situ, you will see that dip very pronounced, as though it were (is?) a major cause of eddy current.

Makes sense as eddy effects can be described as shorted, loosely coupled secondaries of a transformer. IIRC, Mike Sulzer used this principle in an article analyzing qualitative influence of eddy currents on inductance.

[David King]

Next question: did Larry try to patent and trademark every aspect of this most likely pre-existing design?

[Antigua]

Next question: did Larry try to patent and trademark every aspect of this most likely pre-existing design?

The two different gauges of wire for the same number of turns? Yes https://patents.google.com/patent/US4501185A/en .

SUMMARY OF THE INVENTION

The present invention avoids the shortcomings of prior two-coil hum-bucking pickups by winding the coils such that both coils of the pair have substantially the same number of turns but are wound with wire of different diameter or gauge. It has been found that by means of this construction, low frequency cancellation is emphasized, providing more effective elimination of 60 cycle hum without affecting the higher harmonics of the 60 cycle signal which may contribute to the desired tonal qualities. Moreover, because of the difference in impedance characteristics resulting from different diameter wire on the respective coils, overall frequency response can be selectively adjusted to provide improved tonal qualities.

[David King]

"1997-05-06 FP Expired due to failure to pay maintenance fee
Effective date: 19970226"

[Antigua]

"1997-05-06 FP Expired due to failure to pay maintenance fee
Effective date: 19970226"

Well that's good, because $1 spent on this patent is $1 too much.