Low Output from bridge pickup

[Yosh]

Hey Everyone,

Just finished a musiclander build, and I'm having problems with one of my pickups (two alumitone humbuckers). I emailed lace, but based on a no response to a previous tech question, I'm not too hopeful for a response. Oh, and rather stupidly, I forgot to measure resistance before installing.

The bridge humbucker has noticeably lower output compared to the neck, and the resistance pickup measured w/ a cable hooked up to the output jack is half that of the neck pickup (it's around 1.6kohms compared to 3.4--which is spec--and it's 1.1 in the middle position).  I assume I wired something incorrectly, to only get a part of the coil (they aren't true humbuckers) but can't figure out what.

It has a three-way toggle switch and 1 vol, and 1 tone, both cts push/pull pots.

I have each one wired to split with the push/pull pot. The bridge has the black and white wire to 2 on the cts switch, the white wire to 1, and the common goes to ground. I have the same setup for the on the neck pickup, except it uses the volume pot (and the other side of the switch, if it matters, 3, 4, C2. When I pull the volume pot, the resistance cuts in half. Resistance is unchanged on the bridge pup if I pull the tone pot.

Here's a link to the lace wiring diagram:

https://cdn.shopify.com/s/files/1/0026/5469/9593/files/Alumitone_Humbucker_Normal_Split_Wiring_Diagram.pdf?235

Any help would be greatly appreciated,

Yosh

 

[Cowbell Fever!]

I no longer wade into switching however, I would check for a cold soldering joint.

 

[stratamania]

I assume the common goes to ground is C1 to ground, in which case the wiring should be correct. It may be a cold joint as said or some solder that has flowed too much and created a short depriving you of the full humbucker as the white wire is being grounded in both positions.

Perhaps disconnect the white wire from the switch which in normal wiring has no connection. That should give you the full humbucker. If not wire the pickup without the switch in normal wiring that way you have more chance of seeing if the humbucker is working without the push pull wiring.

If you break it down step by step you should be able to isolate where the problem is.

Better to also post pics of things as then we can see if there may be something that gives a clue.

 

[Yosh]

Thanks, Spud and Stratamania.

With your help, I believe I was able to track down the issue. After inspecting the solder joints and not seeing any obvious cold spots, I inspected the switch connections more closely on the tone pot to see any potential shorts and noticed on the back side of the switch solder pads the white wire was bent 90 degrees and contacting the wire running from common to ground. Luckily, it wasn't soldered, and I could just bend it back and clip off the excess. Haven't plugged in yet, too busy cleaning up after a  sick dog, but the Multimeter gave the expected resistance on the bridge pickup in both the pulled and non-pulled position, so should be all good.

Will post a pic of the finished guitar in the musiclander build section once the knobs arrive later this week. Thanks again for your help,

Yosh

 

[Sadie-f]

I didn't have time to weigh in b4, super glad to hear you solved this one the easy way!

Beyond topic, I'll be curious how you like these pickups?! I looked over their product description and briefly read one patent (for a different model), had these thoughts:

"current driven vs voltage driven" sounds to me like utter BS. the physics of a magneto-electric circuit are nuanced still current and voltage have a simple relationship in this case, perhaps they've really done something unique, however that claim is based on this one:

The aluminum water jet cut exoskeleton is then matted to a micro winding using 90% less fine copper wire, a low impedance/high impedance pickup is then created.

How you can use a high electrical conductivity frame to inherently reduce the required windings for a given output escapes me quite utterly. Mostly, i'd expect higher eddy currents in the aluminum to rob some current from the circuit. My inner cynic says, copper wire is expensive (I know, because I've bought enough to do some hand-wound). Also, using exactly the same pickup winding for bridge and neck makes little sense to me.

When you get that doggo cleaned up after, will be glad to hear how it goes

 

[Cowbell Fever!]

I didn't have time to weigh in b4, super glad to hear you solved this one the easy way!

Beyond topic, I'll be curious how you like these pickups?! I looked over their product description and briefly read one patent (for a different model), had these thoughts:

"current driven vs voltage driven" sounds to me like utter BS. the physics of a magneto-electric circuit are nuanced still current and voltage have a simple relationship in this case, perhaps they've really done something unique, however that claim is based on this one:

The aluminum water jet cut exoskeleton is then matted to a micro winding using 90% less fine copper wire, a low impedance/high impedance pickup is then created.

How you can use a high electrical conductivity frame to inherently reduce the required windings for a given output escapes me quite utterly. Mostly, i'd expect higher eddy currents in the aluminum to rob some current from the circuit. My inner cynic says, copper wire is expensive (I know, because I've bought enough to do some hand-wound). Also, using exactly the same pickup winding for bridge and neck makes little sense to me.

When you get that doggo cleaned up after, will be glad to hear how it goes

If Greg Koch likes Fishman products, it's good enough for me. The conjecture in your analysis is unkind to the original poster.

 

[Sadie-f]

If Greg Koch likes Fishman products, it's good enough for me. The conjecture in your analysis is unkind to the original poster.

I would say it's unkind to the manufacturer, sure.

The only thing that matters is does the player like the sound, well maybe their listeners is also important. Great sound can be achieved a lot of different ways, and these pickups may well deliver as promised. As I said, I don't see how, on the other hand, I have my own ideas about how a high output pickup could be designed with relatively less copper in the windings. My speculation and initial testing don't rely on a high conductivity frame, that doesn't mean it isn't a working idea.

Which is why I asked the OP to let us know how they sound. I'm still working on hand wound pickups for my next guitar, however for now finishing the body & neck, and my day job are keeping me too busy to get to that.

 

[Rick]

Lace has got excellent marketing spoo.  I'm wondering though, did they mean "mated" or "matted"?  Matted is the ultimate universal process to induce micro winding into inductive impedance stages in the higher or lower plain simultaneously.  Very interesting.

 

[Cowbell Fever!]

Lace has got excellent marketing spoo.  I'm wondering though, did they mean "mated" or "matted"?  Matted is the ultimate universal process to induce micro winding into inductive impedance stages in the higher or lower plain simultaneously.  Very interesting.

I have noticed after playing or rolling in mud, my dogs fur can get matted.

 

[Yosh]

Hey Everyone,

Dog's feeling better, and I've had a chance to play with them a bit and still have one small wiring problem, but not a big enough one for me to go chasing it down until string change day. Should be easier now that I have a good workflow.

The bridge pickup now works in humbucking mode, but the volume cuts in half in single coil mode and when I tap the side of the pickup under the bass strings with a screwdriver in single mode it's clearly dead, but not in humbucking mode. It does sound really good and spanky split, just got to get the volume issue sorted.  The neck pickup functions properly in single coil mode with only about a decibel or so drop in volume and passes the screwdriver test.

Anyway, I think they sound great so far, although I've been fooled by pickups and guitars before during the honeymoon phase. But I don't really know the physics of it. I just listened to every clip I could find of the pickups online and noticed a clarity I really liked, especially with distortion/fuzz. Most of the (very small number of) humbuckers I've played with seemed muddy to me, and I love fuzz but have never gotten a fuzz tone for myself that I liked, until now.

They take pedals really well, and I was able to get tones I was happy with very quickly. It's almost like they're a platform pickup that lets the character of the amp/pedals shine through (I've tried them with several Tone Junkie kemper profiles and a Spark). Might be a really good choice for someone in a cover band who needs lots of different tones. I also noticed when playing with recorded music, they're easier to hear than other pickups I have, without overpowering the recording. And they sound great split (current issues with bridge pup aside), which hasn't always been my experience

I thought universal bridge/neck was a bit odd too, but they're well balanced.  There's virtually nothing to them when you flip them over. The whole guitar weighs 6.5lbs.