Found this on the SW site. This is the verbiage used on a $4000 USA Custom 24-08. Notice they are 'tuned" not TCI pickups
"TCI-tuned 85/15 pickups: vintage character and modern clarity
PRS 85/15 pickups balance vintage character with modern clarity to deliver the sweet — yet articulate — sound and rich harmonic overtones of vintage humbuckers. Featuring a powerful bridge pickup and neck pickup with the perfect amount of brightness, the 85/15 set packs a real sonic punch, from chimey cleans to full shred. The pickups are treated to PRS’s TCI (Tuned Capacitance and Inductance) tuning, which means the team at PRS has used their years of know-how to sculpt the sound to be perfect to their ears. The end result is a very musical pickup that’s true to its lineage, but updated for the modern player."
The pot resistance in a guitar circuit does not actually make a pickup brighter or darker. What it does is affect the q-factor of the circuit. The q-factor defines the sharpness of the resonant peak. Q-factor is the ratio of inductive reactance (XL) to resistance (R).
Q = XL / R
As R goes up, Q goes down, resulting in a more even frequency response.
Most guitarists confuse a pickup's output with its DC resistance, but that is not how a pickup works. In fact, DC resistance is a poor measure of a pickup's output. What matters is the inductance and self-capacitance of the coil(s) as well as the strength and shape of the magnetic field. Inductance is a factor of the number of turns of wire on a pickup bobbin. Self-capacitance is a function of the number of turns and how the wire is laid down on the bobbin. There are two ways to increase the output of a pickup. The first way to increase output is to use a permanent magnet with a stronger magnetic field (i.e., a magnet with a higher gauss rating). That is why pickup manufacturers eventually switch over to using ceramic instead of alnico when attempting to boost pickup output. Ceramic magnets are available with higher gauss ratings than alinico magnets and unlike alnico magnets, ceramic magnets do not lose strength over time. The second way to increase output is to put more turns of wire on the bobbin. In order to do that with a stock bobbin, the pickup designer has to resort to using thinner wire. Thinner wire has a higher per foot DC resistance rating than thicker wire. That is the only clue DC resistance gives one when attempting to determine the output of a pickup. Higher DC resistance usually means more turns of wire, but more turns of wire also means more resistance per foot of wire due to the physical limitations of stock pickup bobbins.
Now, you have probably heard about wire with magical insulation. There is nothing magical about a wire's insulation other than its thickness. A wire's overall thickness is important when attempting to wind a higher output pickup with lower self-capacitance. A buzzword in the pickup industry is "scatter winding." Scatter winding is little more than imprecisely wound coils. A scatter-wound pickup bobbin usually has a lower self-capacitance than a perfectly wound bobbin. That is due to the fact that individual turns on the bobbin are farther apart (i.e., there is more air in a scatter-wound bobbin). A pickup with a lower self-capacitance usually has a higher resonant peak than a pickup with the same number of turns, but higher self-capacitance. The resonant peak is the frequency at which a pickup is loudest. It is easier to get more wire on bobbin that is perfectly wound by a machine than one that is scatter wound by hand or pseudo-scatter wound by a machine. However, perfect winding equals more self-capacitance, which equals lower resonant frequency (i.e., a darker sounding pickup).
Where the value of the volume pot comes into play is by lowering the q-factor of the circuit. As mentioned earlier, q-factor goes down as resistance with respect to inductance goes up. What happens is the frequency response of a pickup flattens out as the size of the volume pot is increased. In essence, the pickup does not get brighter, it gets less bassy because the resonant peak has been lowered, which widens the frequency response, making it sound brighter.
With that said, has anyone ever wondered why a Strat quacks in positions two and four? It is due to the fact that Strat pickups have a high resonant peak and inductances add in parallel while resistances divide, which means that the q-factor increases, resulting in an sharper resonant peak around which the frequency response drops off at an even faster rate.
In a nutshell, that is why TCI is called TCI, which stands for Tuned Capacitance and Inductance. The only time that resistance comes into play when tuning a pickup is adjusting the q-factor of the circuit.
DCR | Inductance (@ 100Hz) | Capacitance (@ 100kHz) | |
85/15 "S" Bridge | 8.27 Ohms | 5.4 H | 82.2 pF |
85/15 "S" Neck | 7.5 Ohms | 4.6 H | 96.7 pF |
TCI "S" Bridge | 8.65 Ohms | 5.83 H | 37.2 pF |
TCI "S" Neck | 8.75 Ohms | 5.85 H | 48.5 pF |
Well, not exactly. TCI is a process for making pickups, an electronics system, and an actual pickup model name. The TCI "S" pickup is a real pickup simply because that's literally what it is called. It was modeled after the core-line TCI pickup that debuted in the Paul's Guitar in 2019. As for the 85/15 "S" and the TCI "S" being the same, that is also incorrect. First, here's the specs of each model that I've collected personally:
DCR Inductance (@ 100Hz) Capacitance (@ 100kHz) 85/15 "S" Bridge 8.27 Ohms 5.4 H 82.2 pF 85/15 "S" Neck 7.5 Ohms 4.6 H 96.7 pF TCI "S" Bridge 8.65 Ohms 5.83 H 37.2 pF TCI "S" Neck 8.75 Ohms 5.85 H 48.5 pF
Now for the really fun part. Here's the resonance curve of each pickup compared, measured with a dummy load representing 2 x 500k pots and cable/amp capacitance (250k, 470pF):
This chart shows how each pickup responds at each frequency. When Paul mentions things like "pickups have a whistle", this is what he's talking about. All pickups have this curve, and the character of the peak is what defines that whistle note. You can probably barely tell, but the TCI "S" bridge and neck overlap exactly. This is a testament to the TCI-processes consistency, they've chosen the inductance and capacitance and are hitting it. When you match the overall output between the TCI "S" and the 85/15 "S" bridge, the curves are actually identical. So more or less the TCI "S" and 85/15 "S" bridge will sound the same. But the 85/15 "S" neck is not the same as the TCI "S".
Lastly, though it's not crucially important, both models use different baseplate materials. The 85/15 "S" uses brass, while the 58/15 "S" uses nickel silver. Also they have different model names, showing they are indeed different.
I've written an article I'm about to publish on TCI, but I need to have a few more posts here before I can share it. I'm also working on a website called Guitar Pickup Database which collects all the public specs available for pickups, and I'm purchasing every pickup on my own and measuring and recording them.
Just a general question would it be a true statement to say that even the same pickup let’s use a PRS 59/09 would have a different measured impedance/ resistance for each pickup but perhaps have an acceptable range? I would think no matter how your manufacturing process works it would be impossible to get two pickups to have the same value. Also I’m sure it matters how and with what equipment is used to come to these values. Just thinking out loud hear.
This is fascinating stuff. So much so that I bought an LCR meter a few months ago to catalog all my pickups to see if what I think I hear is accurate. I'd be happy to share some of the data I got with you.
Just a general question would it be a true statement to say that even the same pickup let’s use a PRS 59/09 would have a different measured impedance/ resistance for each pickup but perhaps have an acceptable range? I would think no matter how your manufacturing process works it would be impossible to get two pickups to have the same value. Also I’m sure it matters how and with what equipment is used to come to these values. Just thinking out loud hear.
Thanks, I really appreciate it. I want to create this level of detail for every pickup, and I've already purchased 50+ pickups that I'm doing this for. I believe I can post links now, so here's a link to the TCI article - https://guitarpickupdatabase.com/prs-tci-pickups-explained/great info and speculations. I look forward to seeing your work
tHe trUtH iS oUt ThEreYou. Can. Hear. The. Difference.
Bodia For The Win!!You. Can. Hear. The. Difference.
Thanks for posting the specs of the TCI-S pickups. I bought an SE Paul's guitar, and have read articles that state the pickups' DCR is over 11k ohms. In the article they wonder why the tone of the pickups is more vintage-like, and I questioned the accuracy of the specs they quoted. The SE Paul's guitar TCI-S pickups are extremely articulate, have great string definition, besides sounding like real single coil pickups (and nominal volume drop) when split. In my mind they are a real game changer in pickup evolution.Well, not exactly. TCI is a process for making pickups, an electronics system, and an actual pickup model name. The TCI "S" pickup is a real pickup simply because that's literally what it is called. It was modeled after the core-line TCI pickup that debuted in the Paul's Guitar in 2019. As for the 85/15 "S" and the TCI "S" being the same, that is also incorrect. First, here's the specs of each model that I've collected personally:
DCR Inductance (@ 100Hz) Capacitance (@ 100kHz) 85/15 "S" Bridge 8.27 Ohms 5.4 H 82.2 pF 85/15 "S" Neck 7.5 Ohms 4.6 H 96.7 pF TCI "S" Bridge 8.65 Ohms 5.83 H 37.2 pF TCI "S" Neck 8.75 Ohms 5.85 H 48.5 pF
Now for the really fun part. Here's the resonance curve of each pickup compared, measured with a dummy load representing 2 x 500k pots and cable/amp capacitance (250k, 470pF):
This chart shows how each pickup responds at each frequency. When Paul mentions things like "pickups have a whistle", this is what he's talking about. All pickups have this curve, and the character of the peak is what defines that whistle note. You can probably barely tell, but the TCI "S" bridge and neck overlap exactly. This is a testament to the TCI-processes consistency, they've chosen the inductance and capacitance and are hitting it. When you match the overall output between the TCI "S" and the 85/15 "S" bridge, the curves are actually identical. So more or less the TCI "S" and 85/15 "S" bridge will sound the same. But the 85/15 "S" neck is not the same as the TCI "S".
Lastly, though it's not crucially important, both models use different baseplate materials. The 85/15 "S" uses brass, while the TCI "S" uses nickel silver. Also they have different model names, showing they are indeed different.
I've written an article I'm about to publish on TCI, but I need to have a few more posts here before I can share it. I'm also working on a website called Guitar Pickup Database which collects all the public specs available for pickups, and I'm purchasing every pickup on my own and measuring and recording them.
Hi there ! I just wanted to know if you knew what process was supposed to be involve in the tuning of the pickups in relation to the wooden body of the guitar ? Do they have specific benchtests (like a dynometer for a car but for a guitar instead) ?TCI is clearly a marketing ploy. Take an existing design, make a small change (ex: more winds/less winds = increased/reduced capacitance and inductance) and call it "new".
I think the biggest fallacy is that they imply, at least in some of the initial videos for the Core series, that the TCI pickups are tuned for each guitar, but I 100% guarantee that they are not. It's true that every guitar has its own qualities and it would be amazing if they were fine-tuning each pickup to each specific instrument, but that's not the case.
These are tweaks on current pickup designs and nothing more. Nothing to get overly excited about. If you were to try the regular 85/15 next to a "TCI" 85/15 in the SAME guitar, I bet not a single person could hear a difference that warrants the marketing hype.