Post by antigua on Sept 25, 2016 19:03:50 GMT -5
shop.fender.com/en-US/accessories/pickups/custom-shop-fat-50s-stratocaster-pickups/product-0992113.html
I found these pickups to produce a sound that is bold and piano-like. I had ultimately removed them in favor of CS 69's, I was looking for something lower output, more "Stratty". In both my subjective experience, and according to the measures, these pickups are fairly similar to Lollar Blackfaces.
Fender Fat 50 Bridge
DC Resistance: 6.64K
Inductance: 2.579 H
Resonant Peak: 8.36 kHz
Calculated C: 121pF (141-20)
Coil width: 0.5265"
Fender Fat 50 Middle
DC Resistance: 6.76K
Inductance: 2.462 H
Resonant Peak: 9.59kHz
Calculated C: 92pF (112-20)
Coil width: 0.5765"
Fender Fat 50 Neck
DC Resistance: 5.88K
Inductance: 2.415 H
Resonant Peak: 7.90kHz
Calculated C: 148pF (168-20)
Coil width: 0.5240"
The pole pieces are AlNiCo 5. Gauss readings on this set is between 825 and 1050, on the low side for AlNiCo 5.
These electrical measurements came out crazy in all sorts of ways.
1) very different unloaded peaks, but near identical loaded peaks, confirming wildly different capacitance calculations of 92pF, 121pF and 148pF. I've not previously seen a spread that wide with a set of pickups.
2) a lot of variation in values that typically tracks closes. The middle pickup in particular, has a much higher resonant peak than the neck and bridge, yet it also has the highest resistance (and it has a lower Q to suit), but a lower inductance, and it has the fattest coil, 0.05 inches fatter than the neck and middle.
It goes to show how far off all these figures can deviate from spec, and within a set. Fender specs the DC resistance as 6.2k, 6.3k, 6.0k while I measured 6.6k, 6.7k, and 5.9k respectively. Not only are they far apart, but this might be the one and only time I've ever seen a middle pickup with a higher DC resistance than the middle pickup, both in the spec and IRL. So you'd think the middle pickup was supposed to be hot, yet it's inductance is only 2.4H, like the neck pickup, with its rather low DC resistance of 5.9k, while the bridge has a higher inductance of 2.6, as you'd expect. It suggests that Fender's production methods are not as consistent as their popular competitors.
All said and done, the loaded plots and the inductance values are what count for the most when it comes to the final heard tone. The inductance values are within 100mH of the SD SSL-1 and Lollar Blackfaces. They have a similar "loaded resonant peak", in the area of 3.8 to 4.0kHz. The capacitance values and the DC resistances are highly divergent, but they also happen to be values that matter the least in the final heard tone. The variance is capacitance is swamped by the guitar cable's capacitance, and the divergent DC resistances have a negligible impact on the Q factor, so it seems that Fender's production method is accurate where it counts, and less accurate where it doesn't.
It might be that Fender gets the wind counts exact, so you see a consistency in inductance, as the wind count relates very closely to the inductance, but perhaps their source their magnet wire from different places, using winding machines or people that are not consistent in technique or calibration, leading to that wide variation DC resistance, capacitance, and coil width.
Setup details:
Bode plots are made with a Velleman PCSGU250 and the supplied probes in 10x mode, with the function generator feeding a driver coil of 0.48mH, placed on top of the pickup and driven with 2Vpp. The pickup is connected to an integrator circuit, designed by Ken Willmott kenwillmott.com/blog/, with a Velleman 10x probe, and fed back into the Velleman PCSGU250. I measured the probes' capacitance at 20pF, so that amount is subtracted from the capacitance calculation.
The inductance and Q measurements are made with an Extech 380193 in "SER" series mode, and the mean value between the 1kHz and 120Hz modes is recorded. The capacitance value is derived from the inductance and measured resonant peak.
Magnets are tested with a Spin Doctor ER gravitastech.weebly.com/spin-doctor-er.html