Active Pickups?? DIY Guitar that someone gave me to fix up for them.

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Hi guys, I am thoroughly confused, and google is not helping me in the slightest.
I let slip to someone at my new job that I know a thing or two about guitar wiring (I have wired up at least 5 or 6 guitars now, even added a preamp to an old 4 string p-bass) But I digress.


He mentioned that he had some sort of kit guitar that he never ended up finishing, and offered me cash to finish it for him. Fair enough, simple job, I even levelled and dressed the frets for him, since I have the tools and have now dressed 3 of my own guitars and 1 for someone else now. Those frets are nice and shiny now!



I did the frets first because he hadn't told me what he wanted done with the 4 (!) push pull pots in the guitar. I have done coil split, phase reverse and series/parallel stuff before, so while it would be a brainf**k for a day to figure out wiring, I thought I could pretty much do what I wanted with 4 wire pickups and 4 push pull volume knobs! Then I took out a pickup because they had 3 wires each and it was confusing me. I will post the pics on my phone as a reply to this post when it is posted. Easiest way I can figure to do it.


The pic shows what I found: A 3 pin connector plugged into 3 pins sticking out of the pickup! I had never seen this before! And I THINK I know why, as googling around I found that active pickups use this method of connection, one pin being the battery and an earth and signal wire. This explains the single red wire and the other red black combo that are in a single case. He never mentioned active pickups though! I'm not sure he would know what they are! I have certainly never wired a guitar with them! And any search I can think of to Google about active pickup identification either says "actives will have a battery compartment" which helps me not at all, since this thing is literally parts, or they have dirt basic tutorial blurbs that tell me nothing about the actual wiring etc!


I am going to keep looking, but I figured there might be some fine person out there who has messed with active pups before and knows how I might be able to test this definitively before I burn a coil with 9v? I tested the DC resistance and got 50K between the left pin and the middle, and 100k between middle and right, with 150k on the outside pins, predictably. This would suggest to me that these pins go directly to an opamp? Certainly not the coils! And so precisely 50/100/150k! As if a resistor was in there!


To further confuse, I took the jack out, as the other thing about active that I found (I know the basics, just never used them in practice) is that they need a stereo jack to disconnect the battery when you unplug, but this is a very mono jack I pulled out of the guitar just now! I am going to test the resistance of a pot, I will post that with the pics in a few. If they are 250 or 500k I am gonna be so much more confused!


TL;DR I am looking for a way to test if a pickup is active before hooking up power. And if it's not active, why 3 wires? And if it is, why the mono jack and (I am thinking now) probably 250 or 500k pots??



I reckon this thing would never have worked, had he just wired it up like a passive OR tried to wire it active, there is barely room for the wiring between the 4 bloody push pull pots! Let alone for a 9v battery! I may have to do some routing and install a separate battery compartment if I am right about this! And get some nicer pots and a marshall stereo jack from the electronics wholesaler I reckon!


Anyway photos and at least one pot reading forthcoming.


Thanks in advance, and sorry for the ramble, I am just so damn confused right now! :crackup:
 
Pics

The plot thickens!
 

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Okay, The pots are for sure 25k push pull weird as hell pots. See how they come apart? The whole shaft comes out of the thing! I though I broke it! Turns out the knob is attached fast to that shaft and it clicks back in place! I have never seen such a thing!
Best I can make out now that I have had the thing apart:
They expect you to somehow fit a battery between those 4 monstrosities WITH wiring in the cavity as well.
At least ONE of the push pull pots is for the power switch, and if you leave it on it's a flat battery, lead or no lead!
Yup, I'm leaning toward active, and I'm buying some extra hardware, a couple of 25k CTS pots to start with.
I'm now 80% sure these are actives. If anyone has anything to add/tips to give for wiring, please feel free, and if they aren't well I would like to know that as well!
Cheers all.
EDIT: If my 80% assumption is correct, what the hell would the other 3 push pulls hope to do? These things can't coil split, so best they could to is series/parallel and phase reverse on the 2 pickups as a whole, but then not only is the wiring horrendous, but I'm not sure it would sound all that much different with actives! And I still have a 3rd extra push/pull to think of a use for! Thoughts?
Also, the wire I thought was earth turns out goes to the other pickup, I wondered where the active for that one was! And there is no earth to the bridge... yup this thing would have sounded HORRIBLE if it worked at all before I took a look at it!
 
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no set screws on the knobs?
to my knowledge the shafts should not come out !!(in the heat of the moment one could lose the knob and shaft )
new school active pickups are all moving to 3 pin connectors but fail to mark orientation(good thing is improper connection should not cause damage, just no output)


question is there a pickup selector switch anywhere?
 
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no set screws on the knobs?
to my knowledge the shafts should not come out !!(in the heat of the moment one could lose the knob and shaft )
new school active pickups are all moving to 3 pin connectors but fail to mark orientation(good thing is improper connection should not cause damage, just no output)


question is there a pickup selector switch anywhere?


I thought the same thing with the shafts! They have a blade on them so they only go in one of 2 ways, you have to insert them, rotate them, push them down until they push the switch back down (it pulls up when you pull them out) and then you push just a little harder and there is an audible "click" as the little knob on the end gets captured at the bottom of the switch! As I said, I have never seen anything like it, but it appears as if the knobs are stuck fast on the blade things, and this is the way they are supposed to come out! I freaked me out until I heard that "click", I thought I broke the one I took out! But the click sounded like a thing that didn't break anything, and only needed a small bit more pressure than pushing the switch down does. I THINK that this is the way they operate! I can post more detailed pics if you want to see this in action.


Good to know that putting 9v to them won't damage anything, unless they are actually some weird passive I spose...

Yeah it does have a selector up top of the guitar above the 21st fret or so. I took it out and had a look last night, it looks nice on top (gold trim) but the switch feels like crap and looks cheap as hell underneath! I think I'll look for something better that looks about the same installed. I can post pics of that too, but it looks bad so I probably won't keep it anyway. It's a little 3 way gibson style on-on-on switch that simply pushes a piece of metal away from a couple of centre domed connectors, so when you are in the middle both are connected, and pushing the switch either way just pushes on a bit of copper and bends it away from the middle, disconnecting it. The switch barely moves the copper, and it is very bendy and plyable, feels cheap, looks cheap, yuck.



One thing I did want to ask: Have you ever heard of passives that have the 3 pin design? Or is it only actives? I have looked a lots of pics online by now, and only seen active ones with the pins, but not one site has specifically said that these connectors are only on actives (the info on actives is thin on the ground all over the place TBH from what I have found, hence the post here!)


Thanks for the tips so far though, I am guessing that the 3 pins and the 50/100/150k readings pretty much mean 100% active, combined with the 25k pots I pulled out. I am going to replace at least 2 of those with probably alpha pots because the CTS ones are too wide to fit in the hole I think after looking at the pics on the wholesaler.
 
No info on the "kit"? If all that came as a kit, I'd suspect that it'd have a location for a battery and the corresponding 9V connector. You didn't mention if it did. So if they are passive Pups, could they be a center tapped dual coil? Black wire being the common, the reds being the inner/outer coils? I'd do a quick trial wire up of the pick-ups and output connector outside the guitar, plug up to the amp and see what ya got. Worst case if they are active you won't have any output.
 
No info on the "kit"? If all that came as a kit, I'd suspect that it'd have a location for a battery and the corresponding 9V connector. You didn't mention if it did. So if they are passive Pups, could they be a center tapped dual coil? Black wire being the common, the reds being the inner/outer coils? I'd do a quick trial wire up of the pick-ups and output connector outside the guitar, plug up to the amp and see what ya got. Worst case if they are active you won't have any output.


Unfortunately no, seems to be hard to get info out of him regarding this thing!


I thought I had mentioned this, but apparently I hadn't (my bad) but the guitar has no battery compartment, so for actives I was going to have to do some routing, which I didn't really want to do. Thankfully the guy said he was fine with passives, he didn't even know they were active! So I got him some nice white and gold high output jobs from china. They look awesome, have to finish the rest of the thing first though, before I try them out.


I have pretty much definitively found that they are active, just the resistance across the pins is enough for me. I am going to put them in another guitar I have and try them out I think. Since I did a trade free and clear, and spent about as much as they are worth to get the ones that are going in it.


The only "info" I have gleaned from the "kit" (could have just been parts he bought or something, no idea really!) is that I took off the bridge and saddle, and under both is stamped "Epiphone" in the brass. So I am happy that I decided to keep those parts and just clean them up, which they cleaned up really nice, since something better would likely be expensive.


Just waiting on a couple more parts to arrive, gotta buy some CTS pots from my wholesale supplier, and then wire this baby up and install all the new hardware. The frets look nice now, I am pretty happy with the neck in general, even replaced the back neck cover with a nice brass tiger one from ebay that fit like a glove!


Coming along nicely now! Thanks for the post though!
 
Yeah, the resistance does read active. Just seems weird that a kit that has actives doesn't have a spot for the battery. Also you didn't mention if it had the 9V connector.


Nope, just 3 wires with a connector on the pickup end, and bare wires on the other. I think the thick wire (black on one pickup and red on the other) on each are the power wires, and then they have earth and signal.



I don't think the pickups came with the kit somehow, or if they did, I don't know how they expected 4 push/pull pots, complicated wiring AND a battery were going to fit in the tiny cavity in the guitar!


I'll post a pic once it is done, hopefully by the end of next month.
 
modding a guitar's pickup system and controls is a catch 22 in some cases... a cheap or midline axe becomes highly usable and then the antithesis, someone's desire for an "active" pickup system along with a sustainer module turns a valued vintage axe into a garage sale special....


still wondering where to find info on your "unique" pots...?
 
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