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pre for active pickups

While we're on the topic of active/passive vs Hi-Z/Lo-Z... Let's see if I can sum this up right.

Basically, Hi-Z pickups have more turns or thinner gauge wire, while Lo-Z have less turns or thicker gauge wire? If I remember resistance, it's supposed to go down the thicker the lead (wire), but it goes up the longer the coil is.

The gauge of the wire depends on manufacturer, but thicker wire will take more turns to get a higher impedance, and the opposite is true with thinner wire.

On the other hand: actives include an internal preamp in the pickup which then goes to (active or passive) controls, while passives don't have one yet still go to (active or passive) controls.

Correct me if I'm wrong, please. I want to make sure this sums it up more or less.

Sounds good.

Passive controls will probably be different for active pickups, vs passive pickups, as the output impedance of an active pre-amp is much lower than a typical passive pickup. Though I think this is more for keeping noise low, than loading of the pre-amp.
 
I think this is one of those arguments where the semantics revolve around either a strict or loose interpretation of when a signal becomes "active" or whether the implied need for an active onboard preamp places it in the active catagory without passing go or colllecting the $200 first.

Is a pick up passively innocent until preamped and proven otherwize or is it guilty by active association due to an inherant need for an on board preamp?

Low Z pickups generate a weaker amplitude of signal strength primarily due to less coil length (wire composition and thickness play smaller roles assuming a limited range of suitable alloys used for the wire) and based on this design they require some extra on board preamp boost very close to the pick up. It can be actually inside the pickup housing OR a preamp can be added right after the pick ups.

Low Z (aka low resistance) cable and pickups offer the ability to limit or avoid or minimize attenuation of the signal amplitude especially over longer distances. In recording circles some consider the perfect mic pre to be performance wise "a wire with gain" that does not alter anything else in the signal except clear clean signal boost to lift your insturment or mic source as far as possible from any noise floor that may try to sneak into the signal after the preamp...if the noise gets in before the signal hits the preamp the noise gets amplified right along with the signal (this is without throwing any noise specific frequency filtering into the signal at some point).

High Z cable (aka high resistance) will attenuate the amplitude of a disproportionate amount of higher frequencies. So if you have a low z passive pickup outputing at "x" amount of ohms and then send the low z signal down your instrument cable the cable also presents an inherant amount of high resitance loading (adding more resistance) that will add more tone changing attenuation proportional to cable length.

Its like pushing a heavy boulder up a hill...the further up the hill the more steam you lose and the more you slow down....not a perfect analogy but a good visual reference.

Keep in miind that although there are some defined cut off points for where low z becomes high z there is also room for a range of resistance levels within each catagory as well.

At some point most signals either in the recording chain or inside you preamp circuit the signal is transformed to a low resistance signal before hitting the power amp.

On the one hand one could argue a low Z pickup does not become an active pickup just because it has fewer coils it just NEEDS an active signal boost or "pseudo preamp" before it leaves your instrument and ideally before leaving any unsheilded cavity for a low z pick up to be of any real use.

Those who may have been exposed to a deeper level of electrical or audio engineering may not consider an on board preamp as meeting a stricter definition of what is considered an audio preamps today. On the other hand you are amplifying a signal inorder to meet a specific need before it goes into an amplifier or recording chain. In both cases 99% of the time the low z signal that was preamplified at the instrument will hit another higher quality (audiophile like) preamp before being recorded, sent to a power amp / speaker combo and/or both.

Low Z implies the need for active on board circuitry so many catagorize low z as "active pick ups" for simplicity of separating the two types.

Active and passive EQ are completely seperate from active and passive PUPs. Active EQ can boost or cut and passive EQ can only roll off targeted frequencies by increasing resistance with the potenomiter thing a ma bob a lewsky knob.

You can add active EQ to completely passive pickups and in theory you could apply passive EQ to active pickups but since the signal is already low resistance the tone is not as easily affected by adding increased resistance as an already high resistance signal would be.

IMHO both arguments have their points but for the benefit of keeping the concept simple and more true to what in essence is the point I favor using the term active pickups as synomanous with low z.

If you want to get technical - and there are appropriate reasons and times to make the distinction like getting an EE degree or becoming an audiophile preamp engineer then you have a reason to debate what the meaning of "is" is.

Did Bill Clinton lie under oath? Yes he did by all accounts and under his own admission.

Did Bill Clinton commit perjury? By all functional and essential working definitions regarding the concept of perjury I think any objective intelectually honest person regardless of political affiliation would also have to say yes.

Did Clinton technically commit perjury? I'm not a lawyer but it would appear the legal consensus was he skated as close to the edge as you could without technically crossing the line but for all intents and purposes simultaneously drove right through the intent of the law like a Panzer tank over dafadills without technically crossing that line.

Digging deeper regarding how we use definitions...

Should our justice system be restricted to interpret, debate and enforce only the technical merits of law or if given lattitude to take into account interpretting the intention of each law?

Each has its benefits as well as its faults but I'm still for shooting all the lawyers or sending all of them to one big survivors island without a camera crew. Lawyers with adequate bass playing aptitude may IMHO be granted a get out of jail free card if they surrender they liscense to pratcice law along with community service.:bassist: