Post by antigua on Nov 20, 2016 16:33:22 GMT -5
www.seymourduncan.com/pickup/jazz-bridge
www.seymourduncan.com/pickup/jazz-neck
I ordered "a Jazz set with gold metal parts and an AlNiCo 3 magnet" a while back, and recently removed it from a guitar in order to give a set of Toneriders a shot. I had an AlNiCo 5 bar from another Seymour Duncan humbucker, so I swapped it into the CS Jazz for the measurements.
The DC resistance of the neck pickup is consistent with Seymour Duncan's published specs for the Jazz neck at 7.5k, but my Jazz bridge is 200 ohms lighter than the published specs, at 8.2k. I have to take it on faith that this Jazz set is otherwise the same as the production floor Jazz humbucker set.
Seymour Duncan's old "Pickup Comparison Chart" shows DC resistance values of 7.72k for the neck, and 7.9k for the bridge, that's pretty far from both my own measurements, as well as their current published values, though the resonant peaks of 7kHz and 8kHz are not far off from what I have measured:
The closest comparison I have is the Seth Lover set. The Seth Bridge has an inductance of 4.8H to the Jazz's 5.0H, and the Seth neck has a inductance 4.15H, close to the Jazz neck at 4.26H. The loaded peak of the Seth bridge is 2.5kHz, to the Jazz' 2.8kHz, and the Seth neck's peak is 2.8k, the same as the Jazz bridge, while the Jazz neck's peak is 3.1kHz, so despite similar or higher inductance and resistance, the Jazz set still ends up with a resonant peaks that are about 300Hz higher than the Seth Lover set, suggesting that the Jazz achieves a lower capacitance than the Seths. The magnet wire of the Jazz set I have on hand appears to be a bright red color, not the usual dark red of plain enamel. Maybe this bright red wire consists of an especially thick coat.
Needless to say, the Jazz set's reputation as being a brighter PAF set seems to be technically justified. It's still much closer to the typical PAF range than say, the DiMarzio EJ Custom, which has loaded peaks of 4.4kHz and 4.8kHz, and less than half the inductance of the Jazz set. In the market for low output pickups, there seems to be a wide gulf between the 3.0kHz of the Jazz, and the 4.4kHz of the EJ Custom. It seems that guitarists are looking for one extreme, or the other.
Measured specs:
Seymour Jazz Bridge
Series resistance: 8.20k ohms
Slug coil (red & white): 4.09k ohms
Screw coil (black & green): 4.11k ohms
Series inductance: 5.018H
Gauss: 250G slug, 200G screw (AlNiCo 5)
Unloaded: dV: 6.3dB f: 6.97kHz (black)
Loaded (200k & 470pF): dV: 1.9dB f: 2.80kHz (red)
Seymour Jazz Neck
Series resistance: 7.48k ohms
Slug coil (red & white): 3.69k ohms
Screw coil (black & green): 3.79k ohms
Series inductance: 4.255H
Gauss: 250G slug, 200G screw (AlNiCo 5)
Unloaded: dV: 6.0dB f: 7.63kHz (green)
Loaded (200k & 470pF): dV: 2.0dB f: 3.06kHz (gray)
Bode Plots:
This set is uncovered, so it shows Q factors that are unencumbered by eddy current losses caused by most covers.
Since I had the AlNiCo 3 bars on hand, I compared them to the AlNiCo 5. it appears that the AlNiCo 3 is more permeable, because the inductance increased, and the amplitude picked up by by about 0.5dB, and it's likely more conductive, since there appears to be eddy current losses acting on the resonant peaks, especially the unloaded resonant peak.
Underside pic:
These Custom Shop Jazz pickups also features wood spacers. I believe the production models have plastic spacers.
www.seymourduncan.com/pickup/jazz-neck
I ordered "a Jazz set with gold metal parts and an AlNiCo 3 magnet" a while back, and recently removed it from a guitar in order to give a set of Toneriders a shot. I had an AlNiCo 5 bar from another Seymour Duncan humbucker, so I swapped it into the CS Jazz for the measurements.
The DC resistance of the neck pickup is consistent with Seymour Duncan's published specs for the Jazz neck at 7.5k, but my Jazz bridge is 200 ohms lighter than the published specs, at 8.2k. I have to take it on faith that this Jazz set is otherwise the same as the production floor Jazz humbucker set.
Seymour Duncan's old "Pickup Comparison Chart" shows DC resistance values of 7.72k for the neck, and 7.9k for the bridge, that's pretty far from both my own measurements, as well as their current published values, though the resonant peaks of 7kHz and 8kHz are not far off from what I have measured:
The closest comparison I have is the Seth Lover set. The Seth Bridge has an inductance of 4.8H to the Jazz's 5.0H, and the Seth neck has a inductance 4.15H, close to the Jazz neck at 4.26H. The loaded peak of the Seth bridge is 2.5kHz, to the Jazz' 2.8kHz, and the Seth neck's peak is 2.8k, the same as the Jazz bridge, while the Jazz neck's peak is 3.1kHz, so despite similar or higher inductance and resistance, the Jazz set still ends up with a resonant peaks that are about 300Hz higher than the Seth Lover set, suggesting that the Jazz achieves a lower capacitance than the Seths. The magnet wire of the Jazz set I have on hand appears to be a bright red color, not the usual dark red of plain enamel. Maybe this bright red wire consists of an especially thick coat.
Needless to say, the Jazz set's reputation as being a brighter PAF set seems to be technically justified. It's still much closer to the typical PAF range than say, the DiMarzio EJ Custom, which has loaded peaks of 4.4kHz and 4.8kHz, and less than half the inductance of the Jazz set. In the market for low output pickups, there seems to be a wide gulf between the 3.0kHz of the Jazz, and the 4.4kHz of the EJ Custom. It seems that guitarists are looking for one extreme, or the other.
Measured specs:
Seymour Jazz Bridge
Series resistance: 8.20k ohms
Slug coil (red & white): 4.09k ohms
Screw coil (black & green): 4.11k ohms
Series inductance: 5.018H
Gauss: 250G slug, 200G screw (AlNiCo 5)
Unloaded: dV: 6.3dB f: 6.97kHz (black)
Loaded (200k & 470pF): dV: 1.9dB f: 2.80kHz (red)
Seymour Jazz Neck
Series resistance: 7.48k ohms
Slug coil (red & white): 3.69k ohms
Screw coil (black & green): 3.79k ohms
Series inductance: 4.255H
Gauss: 250G slug, 200G screw (AlNiCo 5)
Unloaded: dV: 6.0dB f: 7.63kHz (green)
Loaded (200k & 470pF): dV: 2.0dB f: 3.06kHz (gray)
Bode Plots:
This set is uncovered, so it shows Q factors that are unencumbered by eddy current losses caused by most covers.
Since I had the AlNiCo 3 bars on hand, I compared them to the AlNiCo 5. it appears that the AlNiCo 3 is more permeable, because the inductance increased, and the amplitude picked up by by about 0.5dB, and it's likely more conductive, since there appears to be eddy current losses acting on the resonant peaks, especially the unloaded resonant peak.
Underside pic:
These Custom Shop Jazz pickups also features wood spacers. I believe the production models have plastic spacers.
