Pickup "Seems" to be losing output

[easilyspooked]

Hi All! been a while since i've pestered these parts, but I've got a bit of an issue, done some research, and come up short.

 

Got a GFS Dream 90 in the bridge, and a GFS Retrotron in the neck. Back when i first installed them, the Dream 90 way overpowered the Retrotron, gave the whole thing a nice warm spank, loved it, but I've lately noticed that they have switched up, the Dream 90 barely comes through the mix at all, and if I pop my selector switch over to solo it, the output drops significantly.

 

I've read that this is not demagnetization or likely anything to do with the pickup itself, and that i should check my wiring, the selector switch, and the pots.

 

Did so, found that one of the wires from the pickup to the pot was loose, resoldered it, no change. Checked the security of the wiring to the volume pot, tone pot, selector switch, and output jack, found them all to be fine.

 

I hadn't adjusted the height of the pickup in ages, jacked the poles up, didn't do what i was looking for

 

What's next? Am I missing something important? Could the problem be the pot itself? It is an original stock pot (2004 ibanez artcore - 500k)

 

Any help or guidance would be much appreciated, thanks again!

d

[mrbrown49]

There's a couple possibilities.

 

First I'd try shooting the switch with some contact cleaner. A little oxidation there can suck signal. I'd do the same for the output jack just because.

 

Those pups just don't match well frequency wise. Say you have a two pup guitar and they have the same output but one has a mid scoop and the other doesn't. Even though they'll have a similar volume when playing alone the mid scooped pup won't be heard in the mix as well as the more mid range pup. Is that volume difference the same when you are playing alone, or just when you are playing in a mix?

 

I'd also try adjusting height again. Sometimes that balance changes if you change amps, EQ settings, effects etc. because balance is dependent on frequency response.

[WRGKMC]

The only thing that would do what you're saying is if the coil was partially shorted. You can measure the coil and is it rates close to specs then its only two possibilities. The newness of the sound to your ears has worn off, or maybe you're using different amp settings. In most cases a single coild should be quieter than an HB.

 

If I were to guess, when you first gotthe pup, you dialed that pup in for best tone and could care less how the HB sounded in comparison. This made the single appear to have more sound cause the sound was dialed in for that pup. later, you started balancing the tone so both pups sounded decent and found that balance left the single coil sounding enemic.

[easilyspooked]

interesting, thank you both, i'll try cleaning the contacts.

 

i'd have sworn that the single coil wasted the humbucker in output, been rocking this setup for about a year and a half, but who knows what's lost to memory and fancy.

 

the volume difference is bordering on the obscene, a good solid playing volume with both pickups selected or just the neck pickup selected turns to a basically unheard volume with just the single coil bridge selected. amp hasn't changed, nor its settings. maybe i just need to compensate with some amp adjusting, maybe i'm just looking for a new sound now and am misremebering things.

 

the only reason i discount the dialing aspect of the situation is that my settings have been consistent, all tone and volume pots open full, so i'm thinking you must be right, this must be more an ear thing than anything else and i need to find a way to dial in to get more of the spank i'm looking for that i thought was once provided by the 90.

 

more fiddling is in order!

thank you!

[mrbrown49]

^The pups are on separate Volume pots? Might be worth yanking them out and measuring them. They can have a pretty wide tolerance, and maybe just by chance the SC got a significantly lower value.

 

If they do measure wildly different you could just swap their positions to make the mismatch work in your favor.

[easilyspooked]

they are on seperate volume pots, both 500k stock ibanez pots.

 

so, you're saying i could possibly wire the SC to the current HB pot, and visca versa to even things out a bit?

 

would putting the SC on a 250k pot do anything? (that's what the kids are all into, right?)

[mrbrown49]

 

they are on seperate volume pots, both 500k stock ibanez pots. so, you're saying i could possibly wire the SC to the current HB pot, and visca versa to even things out a bit? would putting the SC on a 250k pot do anything? (that's what the kids are all into, right?)

 

 

I don't know, you'd have to measure them, but they need to be disconnected from the circuit first.

 

Pots are generally speced at +-20%. That means a 500k pot could actually measure anywhere btw 400 and 600. I've never seen that wide a swing but I measured one out at 440 a while back. But, say you have one that measures high and one that measures low. The difference btw the two could have a noticeable affect.

[WRGKMC]

Another possibility is if your using a tube amp, maybe the tubes are getting weak? maybe the other musicians your working with are powering up more, playing harder and just pushing you into the back seat, ears can have degration and if your in an area like me its tree polin season and sinitus and ear problems are in full swing.

 

For the guitar, you can just connect an ohm meter to the guitar jack, then crank the volumes and switch between the pickups and read the difference in ohms. If the HB is greater, then its likely louder as well. If you have a piece of audio equipment with a volume meter, you can plug the guitar in and strum a chord then swap between pickups and see if the pup is truely that much lower in output. maybe the magnet in the pickup has come unglued or has shifted so maybe eyeballing it to make sure its physically sound is in order.

 

A 250K or 300K pot on the single coil would reduce the single coil output but make the two pots more linear balancing the tone of the two, putting a 300K on a HB would reduce its output and even up the output of the two. Different high output strings with higher iron content can make a huge difference too. If all that fails and you have the cavity space, one of these sound fantastic on my P90s, in fact I wouldnt use P90s without it. Very low battery consumption as well. The QTB on this page will do the trick. http://guitarfuel.com/QDD_QTA_QTB_QTP.php

[easilyspooked]

So i was definitely all set to come and eat some crow for your enjoyment, after taking everything out, checking all the connections, failing to achieve any results, i raised the poles, then i checked the actual pickup height, found it to be pretty dern low, i used the GFS mounting rings, and when i compared them to the stock ibanez mounting rings, found that the one's i had one the guitar were literally half the height, so i swapped out the mounting ring, got the whole pickup right up under the strings at a good height, and bam, tone was Exactly what i wanted. I mean, spot on. So i figured that it was all in my head, clearly i had just imagined my original tone and had never achieved it.

 

Last night, band practice, middle of a song, bridge pickup drops out again. The balance between the pickups was perfect one minute, the next, it's all neck. Because of the seemingly spontanious return of my bridge pickup when i jacked the height, and its subsequent random dropout, I've got a loose wire, right? There's still Some output, but it is absolutely minimal. Could the loose wire be up in the pickup (again, as it came back to life when i moved the pickup itself)? Is there any particular reason it would still be sending signal down the line, but at a fraction of the volume from one moment to the next (meaning, i know it can't be a Broken wire, because there is a signal)?

 

Good times! I'll have to go through this thread with a fine toothed comb and compile a list of potentials, and open her up again! Thanks for all your help!

[mike42]

Based on what you're saying in last post I would try wiggle testing everything associated with the bad pup. With the guitar plugged in and amp on, wiggle all the wiring related to the pup to to see if you can replicate the problem.

 

I don't know how you could rule out the prob being in the actual pup winding other than resistance testing, and the switch could still be suspect. But, it sounds to me like the most likely problem is a bad lead, (broken wire making intermittent contact), or a bad solder joint causing intermittent output.

[WRGKMC]

Sounds like a shorted wire or partially shorted coil. I'd first try trimming off the wire where its soldered and redoing the solder connection. Overheating the wire when it was first soldered may have caused the hot and cold wires to partially sjhort together. Next I'd replace the entire wire to the bobbin. this is much tougher and you got to be real careful not to damage the coil wires. If the problem still exists its likely in the coil. It could be where the wire wrapps around the iron or magnet core. If the center block isnt insulated well or if they use littel or no insulation it can take a bump and short against the core. Get two or more wires like this and you loose inductance with coils being shorted together reducing the numbers of active turns thus making the coil weaker. You adjusting the pole pieces and getting intermititant functionality kind of leans this way as well.

 

This is common on vintage fender pups. i have a set of TX specials and one of the poles got bumped. It caused a hum when I touched the pole. luckily I was ablre to reseat and reglue the pole so the hum went away and the pup was fully functional not shorting a bunch or turns like you may be having. Since this damage occurs deep in the coil the only fix would be to rewind the pickup and for all that hassel you're just better off getting another unless GFS warrantees it. If its not the lead cable then I'd say a replacement is in order.

If it hasnt been too long since you got it especially. It does dound like a manufacturer flaw to me. Maybe they will give you a discount if you email them with the honest details about how you love the sound but its causing issues gigging. The good advertisements on forums like this is worth its weight in gold.