k to mV question
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line6man
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I'm assuming that you are trying to equate DC Resistance to output voltage? In which case, the two are unrelated. Otherwise, you would apply Ohm's Law.
DCR is simply the measure of a coil's opposition to a direct current. This does not account for the complex part of the impedance.
Also, the DCR is subject to change with many factors. For example, wiring two coils in series will produce a total resistance of RTotal=R1+R2, while parallel would produce a resistance of RTotal=1/([1/R1]+[1/R2]). Resistance can also change with wire gauge. Thinner gauges of wire will have a higher resistance while thicker gauges will have a lower resistance. In many cases, this difference in resistance can be quite significant, but if the number of turns of wire are equal, there won't be much difference in output. The DCR of a coil changes with temperature as well.
DCR is simply the measure of a coil's opposition to a direct current. This does not account for the complex part of the impedance.
Also, the DCR is subject to change with many factors. For example, wiring two coils in series will produce a total resistance of RTotal=R1+R2, while parallel would produce a resistance of RTotal=1/([1/R1]+[1/R2]). Resistance can also change with wire gauge. Thinner gauges of wire will have a higher resistance while thicker gauges will have a lower resistance. In many cases, this difference in resistance can be quite significant, but if the number of turns of wire are equal, there won't be much difference in output. The DCR of a coil changes with temperature as well.
line6man
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AutoBat said:
When you apply Ohm's Law to complex impedances, you must substitute the impedance for resistance.
It is easy to obtain the DCR of a pickup with an Ohm meter, but the impedance is a much more difficult value to measure or calculate, as it changes with frequency.
Superlizard
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DMRACO said:
Too many.
If you're talking pickups that is.
8k is the sweet spot.
line6man
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Super SauroPOD said:
I would be inclined to agree. A high DCR is most often the result of a greater-than-average number of turns of wire. (Though this is not always the case!) Overwinding shifts the resonant frequency of the coil downward, emphasizing midrange, and costing you treble.
For the life of me, I just don't understand this fascination with high output pickups. While it can be preferable to keep the output level of an audio device as high as possible from early on in the signal chain to keep the SNR high, it is simply not worth sacrificing tone. Most amplifiers and stompbox overdrives/distortions/whatevers have the capability to boost the frick out of the signal, making it as loud as you want it. There is no excuse for not being able to push a gain stage into overdrive.
Cagey
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DMRACO said:
This is one of the great questions of the universe, but it was resolved years ago by Deep Thought. The answer is: 42
Although, the form of the question is similar to "How many gallons is 23 miles per hour?"
In other words, there's no direct relationship between the two. Unless you're asking something along the lines of "what color is a blue jay?"
You'll have to be more specific.
line6man
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DMRACO said:
The only way you're going to figure out the output level is to physically measure it. I've been asked to measure the output of a bass a couple of times for various threads on TalkBass, and I approximate the best I can by watching the waveform dance in real time on an oscilloscope screen. It's quite difficult to identify exact measures, given the many variables involved, but of course, I take it you're more interested in a ballpark figure of how the pickup in question will compare to others. If you want to know what pickups output in milliVolts, find someone with an oscilloscope to let you play a guitar into. (And before anyone hassles me, yes, there are sophisticated measuring devices which can measure signal voltages over time and provide peaks and averages, but this equipment is very expensive and not as easily accessible as a common oscilloscope.)
TroubledTreble
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If I understand correctly you are trying to figure out how many mV a 15.8k ohm pickup will produce. It is not possible to calculate it properly. Only testing will give good results.
There is not a standardized test. The type of magnet, wire, size and shape of the coil, metal content etc. will all effect the outcome, as does the method of testing. So for every manufacture there will be different results. mV should only be used as a ballpark number, but even then it can be misleading.
There is not a standardized test. The type of magnet, wire, size and shape of the coil, metal content etc. will all effect the outcome, as does the method of testing. So for every manufacture there will be different results. mV should only be used as a ballpark number, but even then it can be misleading.
line6man
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Alfang said:
That's usually insignificant.
Most amps have a high input impedance, which means that there is little loss in output voltage. While pots do attenuate a pickup's output, turning your controls all the way up places a resistance parallel to the pickups only. This resistance doesn't have much of an effect on the low frequencies.
If you want to simulate a real world load, try a 220k resistor across the pickup. This is about the same as the load from a volume pot, and the input impedance of whatever you are measuring with shouldn't be too far off from that of a guitar amp. If it's too high, drop the resistance a touch.
O
OzziePete
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...somewhere within this Thread I think my head imploded... :sad:
Still regret leaving high school so early. This conversation shows me that there was so much more to learn.
Still regret leaving high school so early. This conversation shows me that there was so much more to learn.
dmraco
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I guess my ultimate question is what is the output of Duncans Stacked P-90? We can leave the rest of this conversation to the Physics gurus. I was lost after my 1st question.
The good news is there is TONS os knowledge lurking behind the scenes with the board members.
Now is someone can just explain the possability of TIME TRAVEL to me so I can go back and buy a '52', '57 thru '60 Les Pauls new that would be great.
The good news is there is TONS os knowledge lurking behind the scenes with the board members.
Now is someone can just explain the possability of TIME TRAVEL to me so I can go back and buy a '52', '57 thru '60 Les Pauls new that would be great.
TroubledTreble
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Napoleon's Uncle had a time machine, perhaps you can find one on the internet like he did. :tard: :laughing7:DMRACO said:
drewfx
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There is no way to convert k to mV because they are measuring completely different things. You can't really use Ohm's law, because in PU's the current isn't known/constant.
I believe the best way to get a mV reading would be to read it directly, starting with a consistent, reproducible, predictable disturbance of the PU's electromagnetic field. And to compare 2 PU's output in mV, you'd need to do an identical test on each PU.
I believe the best way to get a mV reading would be to read it directly, starting with a consistent, reproducible, predictable disturbance of the PU's electromagnetic field. And to compare 2 PU's output in mV, you'd need to do an identical test on each PU.
dmraco
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tfarny said:
yes...sounds right since it is a p-90...kind of. As I read it, it is a stacked p-90, with two coils and it has 4 wires so it can be tapped. Once taped output in increased but you look the hum canceling effect.
Here...what you you think?
http://www.seymourduncan.com/products/electric/specialized/progressive/stkp1_p90_stack/
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