Magnet swap on an active mount Pegasus?

[Seashore]

Hey all - first post here. I recently put a 7-string Pegasus in an Epiphone LP and it's not quite what the guitar needs in a bridge pickup. I'd like to try swapping in a ceramic magnet. It's in an active mount housing - essentially just a pickup with no tabs in a plastic box. It's not sealed but I can see what looks like some glue holding it in place.

Does anybody have experience with removing the entire pickup from the housing? If so, what should I use (heat gun, putty knife, etc)? Or would just taking the baseplate off leave me enough space to replace the magnet? Or is this just an all around bad idea, given the plastic housing? I don't want to destroy the pickup. Could always use it as a neck pickup and find something else for the bridge.

Thanks, cheers, nice to meet you.

_____

Edit - this ended up working and turned out ok. Trial and error documented below.

 

[jeremy]

welcome to the forum!

i dont have any experience with trying to open or mag swap a active housing pup. can you post a few good pics of the pup? if you can take the baseplate off, then you should be able to swap

 

[Seashore]

Hey, thank you man. Hopefully these photos are good enough. I have a couple other angles but they all show the same thing.


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[jeremy]

so id think that if you backed the screw poles out of the baseplate and removed the four brass screws you would be able to pull the baseplate off gently, be cautious of the wire bundle that goes through the baseplate. it should slide though the hole but there will be connections between the bobbins and that and you dont want to mess any of that up so go very slowly and look as you pull it off. im guessing youll be able to pull the plate up enough to rotate it out of the way far enough to swap the magnet, then reassemble but please take caution so you dont kill your pup. if this was my pup, id feel confident exploring in the way i just described, but would proceed with caution since ive never done it before on this style pup

 

[Seashore]

so id think that if you backed the screw poles out of the baseplate and removed the four brass screws you would be able to pull the baseplate off gently, be cautious of the wire bundle that goes through the baseplate. it should slide though the hole but there will be connections between the bobbins and that and you dont want to mess any of that up so go very slowly and look as you pull it off. im guessing youll be able to pull the plate up enough to rotate it out of the way far enough to swap the magnet, then reassemble but please take caution so you dont kill your pup. if this was my pup, id feel confident exploring in the way i just described, but would proceed with caution since ive never done it before on this style pup

Thanks very much, I appreciate your advice! I'll give it a shot. Hopefully I can update this with some progress pics in the next few days. Cheers dude.

 

[Mincer]

Yes, certainly update us. I don't think this sort of thing has come up on the forum for awhile (ever?) so your experience will help others.

 

[Seashore]

A detour into bling: this 7-string LP (the new Epiphone Matt Heafy signature model) has gold hardware. I hate gold hardware, but here I am anyway. I ordered some gold fillister screws to replace the exposed pole pieces in the Pegasus. They're about 3/16" shorter than the nickel-plated screws it came with. I'm already shaving off some treble and boosting the bass and mids to get the sound I'm looking for, so I suspect this will be a step in the wrong direction tonally, but I want to try it anyway before I crack the thing open.

 

[Seashore]

The baseplate came up easily when I pried it with a flathead after removing the screws. The adhesive along the edges seemed brittle; it just popped off. This doesn't seem like a big deal. The rest of the pickup appears to held in place well within the plastic soapbar housing; when I put pressure on the exposed pole pieces from the outside to see if I could dislodge it, it didn't move at all.

When I raised it enough to see underneath, I noticed that there were ground wires soldered to the baseplate in two places, seen here:



They're diagonally across from one another, which makes this very tricky. The small ground wire coming from the outside of the coil broke right after I took the above photo; even gentle tilting of the plate with a lot of caution was too much. The broken tip of the wire sticks up:



And here, you can see the two solder locations on the inside of the baseplate. The joint where the wire broke off is on the upper left. I'm going to try to solder in a short length of wire to reconnect the small ground wire to the plate with a little more wiggle room. The new ceramic magnet is in place in this pic, too.



Here's the original A5 magnet before I removed it:



Here are the A5 and the ceramic side by side. The ceramic is from Mojotone. They're the same width and thickness, and nearly the same length, so I didn't have to mess around with spacers.





Hopefully I can get this little wire soldered back on without overheating anything else. I'm not great with stuff this fiddly, and my iron is a bit weak, but I think I can make it happen. If anyone feels like chiming in with pointers, I'll take them gladly.

Ironically I had finally gotten the Pegasus dialed in to a sound that I thought was pretty darn good before I undertook this, so who knows if it'll be worth the effort. Next step is to get this buttoned back up. Wish me luck...

 

[Seashore]

Update - the small broken ground wire came off completely when I was trying to reattach it to the baseplate. Too much heat, I guess. I'm going to see if it's possible to remove the entire assembly from the soapbar housing so I can get it reconnected.

 

[Seashore]

I raised the pole pieces on either end of the pickup so I could apply some more pressure from the outside to try and move the assembly up and out of the housing. The bobbins move somewhat independently of one another so I took a lot of care to work them up slowly in tandem. I also flexed the housing slightly away from the sides of the bobbins to break the wax seal and make them easier to wiggle up. I've gotten it to the point where the solder joint on the grounding tape is revealed; I'm going to try reconnecting this to the baseplate and then pushing everything back into place.

 

[Seashore]

I made a short jumper out of some old wire I had laying around. I attached it to the baseplate first so the heat from the baseplate attachment didn't desolder the more delicate joint at the bobbin shielding, which was part of my mistake last time. I bent the wires at the bobbin around each other and crimped them a bit (seen here) before soldering, so the joint is more durable if I try doing anything this harebrained again:



This tucked down nicely into the corner of the soapbar housing when I pushed everything back down. I went slowly to make sure the bobbins didn't get too far apart from each other, got everything seated nicely, screwed the baseplate back on, and popped it back in the guitar. Mission success! Everything works fine, and I now have an active mount ceramic Pegasus installed in my guitar.



Was it worth it? I don't know. My main guitar is a Gibson Explorer and I had a ceramic pickup in there for about 15 years before swapping it out for an A5 a few months ago. I'm not sure I have a preference. The ceramic magnet in the Pegasus brings the output (noticeably higher) and feel (a bit stiffer/harsher) more in line with what I've come to expect when I play; it's a bit more zingy, more "metal". Pretty much exactly what I assumed when I thought about the difference between A5 and ceramic. It's not necessarily "brighter" overall but the high mids where I hear pick attack and the bite of distortion seem shifted up a bit, and the mids in general are more prominent (I kept the same strings throughout this process so I wouldn't just be reacting to the sound of fresh strings). So I felt right at home when I fired it up.

On the other hand, it's less forgiving; the sound is a bit more precise and jangly, and little inconsistencies are more apparent. Whether I keep it in or not will come down to how it fits in with the other guitar at band practice, and that's where I'm beginning to suspect the original A5 will have an edge. Hopefully my little red jumper mod will make it less of a headache if I ever want to swap back.

The only permanent damage is a scratch on the pickup cover where my flathead slipped out while I was adjusting a pole piece. Also, little flecks of wax got everywhere. Now maybe I can stop tone chasing and play the thing for a bit.

 

[krovatron]

Did you remove the Fluence bridge pickup and modify the wiring for the passive pickup? Curious how you're running both an active and passive pickup.

 

[Seashore]

Did you remove the Fluence bridge pickup and modify the wiring for the passive pickup? Curious how you're running both an active and passive pickup.

I'm not. i wired the Pegasus to the jack and ground for now and disconnected everything else internally. Just leaving it in place for now so the guitar doesn't have a bunch of empty spots while I get everything else together for it.