LP Upgrade - issues!

[L_Mo]

Hey All,

 

I posted earlier this week that I was upgrading my LP. I ordered Fat PAF pickups from GFS, new pots, andx some wire. Well, everything arrived in good condition and I installed it tonight, and I'm having some issues...

 

1) The bridge pickup is a -lot- quieter than my neck pickup. The neck pickup is 10K, the bridge pickup is 14K - shouldn't the bridge be louder? What are possible causes or things to check?

 

2) The tone knobs do a -lot- less than they used to. I used 0.02uf caps and 500K pots. I soldered the caps between the volume and tone pots. I noticed that some diagrams suggest using a wire from the volume to the tone, and putting the cap between the tone and ground - will this have any effect?

 

3) Coil-tap. This seems to do very little. At the moment I have the two "inner" wires from the pickups (that come soldered together) going to a terminal on the push/pull switch, and it gets grounded if I pull out the pot - that's how it's supposed to work, right? Measuring the resistance between ground and the switch gives half the pickup resistance (7k and 5K), so that looks right, and then it goes to 0 when I pull the switch, so it seems to be working. Does it just not do that much? When I say "not much" I mean I can mostly tell something changes as I switch it, but if I didn't know which state it was in, I wouldn't be able to tell from listening.

 

The bridge pickup volume and lack of tone switch has me worried. I would say I'm happy w/ the upgrade, because the bridge pickup sounds quite nice, but I'm definitely not satisfied by the bridge pickup output...

[TWANG]

how high is the bridge pup and how high neck?

 

raise/lower each until they are balanced for volume.

if the sound is **** then, so are the pups.

 

at those ohms you should have a bridge pup as loud as the neck with the height being the same.

pretty close..

 

 

 

go to .047 caps. I think rat shack has the fat green ones.

keep the 500 K pots.

 

you can use the caps either way. pretty much the same effect, it shunts to ground.

 

there must be ten clear diagrams for how to do coil tap online. copy one.

 

you should have a fat loud signal, and a soft thinner signal. clearly defined by the coil tap switch.

 

TWANG

[RotcanX]

1) The bridge pickup is a -lot- quieter than my neck pickup. The neck pickup is 10K' date=' the bridge pickup is 14K - shouldn't the bridge be louder? What are possible causes or things to check?

 

Like Twang said, check the relative pickup heights. Neck should start at 3/32" from the strings; set the bridge to 1/16".

 

2) The tone knobs do a -lot- less than they used to. I used 0.02uf caps and 500K pots. I soldered the caps between the volume and tone pots. I noticed that some diagrams suggest using a wire from the volume to the tone, and putting the cap between the tone and ground - will this have any effect?

 

Are the new pots audio or linear taper? They should be audio.

 

3) Coil-tap. This seems to do very little. At the moment I have the two "inner" wires from the pickups (that come soldered together) going to a terminal on the push/pull switch, and it gets grounded if I pull out the pot - that's how it's supposed to work, right? Measuring the resistance between ground and the switch gives half the pickup resistance (7k and 5K), so that looks right, and then it goes to 0 when I pull the switch, so it seems to be working. Does it just not do that much? When I say "not much" I mean I can mostly tell something changes as I switch it, but if I didn't know which state it was in, I wouldn't be able to tell from listening.

 

Sounds like you have it straight. Hmm. Sometimes the difference is subtle.

 

[/quote']

[V-Type]

The bridge should be noticeably Hotter. You may have the coil tap wires backwards or wrong.

Sounds like your only running on one coil IMO.

[carverman]

Hey All' date='

 

I posted earlier this week that I was upgrading my LP. I ordered Fat PAF pickups from GFS, new pots, andx some wire. Well, everything arrived in good condition and I installed it tonight, and I'm having some issues...

 

1) The bridge pickup is a -lot- quieter than my neck pickup. The neck pickup is 10K, the bridge pickup is 14K - shouldn't the bridge be louder? What are possible causes or things to check?

 

2) The tone knobs do a -lot- less than they used to. I used 0.02uf caps and 500K pots. I soldered the caps between the volume and tone pots. I noticed that some diagrams suggest using a wire from the volume to the tone, and putting the cap between the tone and ground - will this have any effect?

 

3) Coil-tap. This seems to do very little. At the moment I have the two "inner" wires from the pickups (that come soldered together) going to a terminal on the push/pull switch, and it gets grounded if I pull out the pot - that's how it's supposed to work, right? Measuring the resistance between ground and the switch gives half the pickup resistance (7k and 5K), so that looks right, and then it goes to 0 when I pull the switch, so it seems to be working. Does it just not do that much? When I say "not much" I mean I can mostly tell something changes as I switch it, but if I didn't know which state it was in, I wouldn't be able to tell from listening.

 

The bridge pickup volume and lack of tone switch has me worried. I would say I'm happy w/ the upgrade, because the bridge pickup sounds quite nice, but I'm definitely not satisfied by the bridge pickup output...[/quote']

 

Ok, maybe I can offer some help. I've got the GFS Fat Paf and Crunchy Paf on my "trick pony" Epi LP Custom,.

The bridge is around 13.5 K which is normal for a bridge p_up.

 

There is nothing wrong with the volume on these GFS p_ups, IMO. but they need to be raised quite high.

If your bridge p-up came with the standard GFS ring, then swap it out for the higher EPI bridge ring and

raise the p-up up as far as the screws allow without touching the strings, you should notice more output.

 

2. I use both .022uf and .047uf caps wired into a push-pull switch on tone tone pots, there is a bit of

difference. My tone caps are wired on the push pulls first, then over to the tone pot (with one lug open),

middle lug has the selected cap connected to it, and the other lug grounded to the tone pot case.

The center of the tone pot (wiper) goes to the wiper of the volume pot.

 

3. As far as coil tapping, you need to experiment with them.

The two coils are 180 degrees out of phase with each other as is the nature of the humbucker.

The "start of the winding" BLK, end of winding WHT for the N coil and the start GRN/end RED of the

S coil come out on the FAT pafs, so its a matter of flipping the S coil wires around, and you should

notice a "nasal sound" when that happens.

[L_Mo]

I think my problem is mostly caused by pickup height. I set the pickup as high as I could, but it was still maybe 1/4" away from the strings. I think as Carver pointed out the GFS ring is just too short. unfortunately, I've changed colors from stock so it would look a little stupid with the orig. ring in there. Is there anywhere I can order rings that are actually the right size in black?

 

However, atm my bridge pickup is really close to the strings and the neck pickup is farther away, yet they're the same volume. Does that mean something is wrong w/ the bridge pickup? I just got them, so if they need to be replaced I guess now is the time to ask...

 

For now I've just put some soft spongy material under the ring to raise it up. Works fine, but there's a noticeable gap.. It'll work until I find a replacement ring or exchange the pickup if need be.

 

One question about the wiring: It's important that all grounds are connected, right? So for example, I bent the pin end pin of the tone pot up and soldered it to its case, and then I soldered a wire between the two tone pot cases and a wire from each tone pot case it's volume pot case... etc. etc. So here's another question: is it important to ground to the pot cases? The soldering iron I borrowed for the weekend has a very fine tip and getting solder to stick to the case is a PITA. With the surface tension it just melts into a ball and rolls off the pot.

 

So the question is: Can I -not- ground the pot cases? Every pot has an electrode that should be grounded, so can't I just connect all grounds to that electrode, and then chain all those electrodes together to form the common ground? It's not any more or less soldering, it's just connecting wires to that electrode instead of the casing...

 

Thanks for your help guys. I definitely like doing this stuff by hand, hopefully I'll get the hang of it though!

[carverman]

..snip!.. the GFS ring is just too short. unfortunately' date=' I've changed colors from stock so it would look a little stupid with the orig. ring in there. Is there anywhere I can order rings that are actually the right size in black?

 

However, atm my bridge pickup is really close to the strings and the neck pickup is farther away, yet they're the same volume. Does that mean something is wrong w/ the bridge pickup? I just got them, so if they need to be replaced I guess now is the time to ask...

 

I bent the pin end pin of the tone pot up and soldered it to its case, and then I soldered a wire between the two tone pot cases and a wire from each tone pot case it's volume pot case... is it important to ground to the pot cases?

[/quote']

 

Reply: Use your original EPI bridge ring for now..the color can be sorted out later..get it working the way

you want it first. Stew-Mac have all sorts of rings. plastic, metal..low and tall. The plastic ones

are cheap (under $4) but it's the cost of the shipping that's going to set you back. Personally, I

would go to a paint store, get a cream (or whatever colour you want), spray can of good paint and paint

the original Epi ring. It's plastic and it will take the paint.

 

What kind of volume are you expecting from the bridge p_up? It's an Alnico II p_up and that is more of a vintage

style magnet strength. If you want more volume, go for an Alnico V style p_up which has a lot more strength.

As as height of p_up vs p_up signal strength, the strings vibrate more around the neck than at the bridge,

and the magnetic lines of force, (as presented by the Alnico II bar magnet in the p_up) will have more signal

amplitude because the strings vibrate more in that area than at the bridge.

 

IMO, it's better to use the pot cases for all grounding. You need a tip with more heat to heat up the pot cases.

I use a Weller temp controlled iron and the fine tip doesn't provide enough heat . What you need to do is get

another iron that has a bigger tip and heat up the pot case to deposit enough solder on the case, that you can

work with the smaller iron to attach the shields/ground wires.

The "grounded" lug may work to some degree, but it's attached to a resistive element inside the pot. If you

have cold solder joint, you may have some "wierd" buzzing problems.

[L_Mo]

Yeah for now I've got the pickups in position correctly - I'll worry about the short ring after I get the tone corrected. As far as volume, I'm was expecting them to be more-or-less the same. I understand the bit about string vibrations being different, but there wasn't such a difference with the old set. BTW these are Alnico V magnets: http://store.guitarfetish.com/gfsfatpafbln.html

 

The volume thing is better now, I just didn't expect that the bridge pickup would need to be so much closer than the neck pickup to get the same volume...

 

Regarding grounding: You're right. I have the same weller fine-tip iron, unfortunately I don't have any other tips. I'm borrowing this one, so I might have to pick up one for myself with a broader tip. That's probably a better solution than doing something weird with the wiring.

[carverman]

I understand the bit about string vibrations being different' date=' but there wasn't such a difference with the old set. BTW these are Alnico V magnets: http://store.guitarfetish.com/gfsfatpafbln.html

The volume thing is better now, I just didn't expect that the bridge pickup would need to be so much closer than the neck pickup to get the same volume...[=endquote']

 

Ok, something may be off a tad here with the on-line advertising. I don't have a guass strength meter to measure

the underside of the pickup where the bar magnet is situated, but using a crude needle nose pliers trick, the

original Epi magnet (HOT CH) appear to be stronger attracting the pliers than the FAT paf, but I don't know

what formula was used in this case for an overwound p_up. Obviously with 14 K dc resistance, you would expect

a stronger magnetic material around the bobbins. I would suggest that you might email Jay and ask him about this.

 

Here's the field strength (Gauss per cm3) of the three types used in pickups.

Alnico II 450 7.0

Alnico III 450 6.9

Alinico V 525 7.0 * should be a 25% stronger magnetic material

 

Years ago, I installed De-Armond 2000s in my old Epi Triumph and those were very loud and the magnet

pole pieces (which adjusted up and down individually) were very powerful. There is a drawback to this of course

that magnets that powerful too close to the strings will dampen the vibrations(decrease sustain).

[L_Mo]

You might be on to something! I felt the magnetic strength by tapping pliers on the screws (the new ones are covered, so I can't tap the other pole). Anyway, the neck pup feels -much- stronger than my bridge pickup. I can't tell if there's a difference between my neck Fat paf and the epi original, but there's a really noticeable difference between the new neck and new bridge pickups. I don't have a proper meter either, but it seems like a big enough difference that it's not just my imagination and wishful thinking.

 

I've already e-mailed guitarfetish (is that Jay?) that the pickup doesn't respond well to tone and requires to be really really close to the strings to get any reasonable response. I'll add that I think the magnet is weak and hopefully he'll let me exchange it.

 

I'm toying with the idea of switching to a crunchy paf, but I'm not sure. It's also 14Kohm, so I'm assuming it has a stronger magnet? Any thoughts on that?

[carverman]

You might be on to something! I felt the magnetic strength by tapping pliers on the screws (the new ones are covered' date=' so I can't tap the other pole). I don't have a proper meter either, but it seems like a big enough difference that it's not just my imagination and wishful thinking.

 

I've already e-mailed guitarfetish (is that Jay?) that the pickup doesn't respond well to tone and requires to be really really close to the strings to get any reasonable response. I'll add that I think the magnet is weak and hopefully he'll let me exchange it.

 

I'm toying with the idea of switching to a crunchy paf, but I'm not sure. It's also 14Kohm, so I'm assuming it has a stronger magnet? Any thoughts on that?[/quote']

 

I got both bridge versions. The magnet strength from the very crude test appears to be about

the same. I feel that they are ok for economical p_ups for less expensive guitars, but there are

better "boutique p_ups" out there obviously.

 

Go to www.Harmony-Central.com and click on electric guitars, search in the box for GFS Crunchy Pafs. There should

be 8 or so user ratings on them.

[tulsaslim]

My brother had exactly the same problem with the same guitar & same pickups. It drove him crazy since he's changed many pickups in his time. It turns out there was something oddball about the way you wire them up. I can't remember the details but it was a simple but unconventional fix involving one of the grounds. I'll try to find out exactly what it was for you. All I can tell you is that after he switched a couple of wires around the bridge pickup came to life & he commented that "he's never wired one up that way before".

 

They sound great once he got it right.

[lostindesert]

When soldering on the pot's cases use a knife to scrape the case on the spot where you want the ground wire.

Bridge pickup's are always closer to the strings then the neck pickup.

Try the Gibson adviced pickup height, neck PU 3/32'' on both E-strings and bridge PU 1/16'' on both E-strings. Measured when pressing both E-strings at the last fret (22).

I've used the parallel/series/single coil and out of phase settings in the past with Seymour Duncan and DiMarzio

humbucking pickups and was very pleased with it, maybe you're doing something wrong.

A good book about these issues is the Guitar Player Repair Guide by Dan Erlewine.

 

Good luck,

 

Peter

[captmidnight]

When soldering on the pot's cases use a knife to scrape the case on the spot where you want the ground wire.

Bridge pickup's are always closer to the strings then the neck pickup.

Try the Gibson adviced pickup height' date=' neck PU 3/32'' on both E-strings and bridge PU 1/16'' on both E-strings. Measured when pressing both E-strings at the last fret (22).

I've used the parallel/series/single coil and out of phase settings in the past with Seymour Duncan and DiMarzio

humbucking pickups and was very pleased with it, maybe you're doing something wrong.

A good book about these issues is the Guitar Player Repair Guide by Dan Erlewine.

 

Good luck,

 

Peter[/quote']

 

I was just about to say something about ruffing up the pot. sand it with some course sandpaper so the soilder has something to "grip" to. If you have any liquid flux for eletronics around brush a little on, that will help also.

Capt

[L_Mo]

Ok I think I've got it all sorted out. After everyone's comments about the solder I decided my lab's Weller tip was just too small (I work at a microelectronics lab, so things tend to be for smaller applications) I went to radio shack and got a crappy $9 iron w/ a bigger tip.

 

I re-did everything, and it seems to be working now. coil tap acts as expected. Still not an overwhelming effect, but it's working. Tone knobs work well. I did replace the caps with 0.047uf ones, which might have made the difference.

 

Re-soldering everything probably was the biggest thing, as this one was able to heat the wires more effectively. I also scratched the pot casings, and that helped with adhesion.

 

Thanks for everyone's good comments, I'm glad I was able to get it all wired up and sounding good!

 

One last question about grounding: how extensively should you ground? As in, when a wiring diagram says "ground" - do you connect all those together to have one common ground? On my first attempt, I connected all the grounds. This time I was planning on doing that, but I checked it after wiring up each pot and everything worked. So all my pots have individual grounds... For example on my tone pot I connected the ground pin to the pot casing through the cap, but the casing as "ground" isn't connected to anything else. Should I go back and ground it, or will this be okay?

[freednighthawk]

Well, it should work, but its deffinantly not the prefered method. Chances are its grounding itself off of the shielding paint or plate (not sure what they are still using) I would suggest grounding the pots, just to avoid any potential headaches later.

[lostindesert]

Connect all pots and switches with a ground wire.

 

peter

[garyelcrrt1281733995]

Many of the quieter rigs have wires soldered to the pots on either side, so they are all one big circle.

 

Edit

 

The object is to make ALL of the metal in the guitar part of the same mass.

[Dave]

I think most people end up with the neck pup all the way down and the bridge raised to even the output. My Epi LP is that way with matched SD pearly gates and so is my Gibby LP with 490/498s. The neck pup is in a position where the string oscillates back and forth much more than it does at the bridge, so the bridge needs to be hotter to have enough output. I try to keep my pickups fairly low to balance the sound of the wood with the direct drive of the strings. If you get too close to the strings, you get loud output, but it is quite a bit shriller than it is when the pups are lowered. Lowering produces a warmer sound.

[old1]

I have the GFS Fat PAFs in my Epi LP studio. LIke you I found the Neck PUP to be louder than the bridge. I set the Bridge at the Gibson suggested 3/32". I had to adjust the Neck PUP much lower, flat with the top of the ring to get close to the same output. I don't mind this since I want more body sound on the neck position anyway. Still I'd like to adjust it a bit higher to get a bit more pick attack but can't because it will upset the balance. I'm going to try an experiment and add a resistor in series with the Neck PUP. This should lower the the output enough for me to raise it and still have the balance between Neck and Brdge. I'l let you know how it works out.

There's a noticeable difference between my single coil vs humbucker sounds. I don't know whether any Humbucker can get as good a single coil sound as a good single coil, however I'm happy with the versatitlity the coil cut provides.

I also reversed the neck PUPs wiring polarity to get an out of phase sound when the PUP selector is in the middle. I like it but some may not be fans. Between the coil splits and out of phase position I get a good variety of usable sounds.

[TWANG]

sometimes I think folks just don't realize how much more string vibration is coming from the neck position.

or what pole pieces are for.

you get too close you overdrive. you get too far away you get thin..

crappy pickups will still blend well enough. but you may have to compromise in both directions..

 

look at what old fender spec output is.. compare that to current popular output.. about 1/3rd!

7.5 to 8Kohms for me is the magic number.

 

I'm pretty much convinced that any good poly cap is fine.. brand name caps in guitars don't seem to my ear to have much difference, though I still install mallory or sprague just for the voodoo.

besides. they're still cheap and look absolutely ****.

 

CTS, CGE, Alpha pots.. slightly different feel, still excellent choices all.

 

Had a GF who made pots.. she said the us manus, name brands for tvs, stereos, etc, were really all from the same factory, same stuff.

stamped differently.

Now, those are all overseas jobs, and probably not much different from what we were making.

 

We're kinda the last bastion... tube freaks and guitar players in general.. who still want the true 1940s technical quality.

That we can go to war with this stuff thing..

 

I'm sticking a PAF style and output 12 pole humbuck, Kent Armstrong in a dimebag style guitar I'm just finishing up.. I want to compare it to the stock imports, higher output, and a set of epi LP, also higher output, pickups.. it's just a test.

 

I'll post a pic of the guitar when I'm done.. it's pretty cool. black hardware burgundy sparkle paint.. probably I chose too pretty a color for the metal heads!

(what's with all this black? and camoflage? usually people want you to see thier guitar. *g* )

[smokestack]

Don't forget that it's normal for the neck pickup to be somewhat louder than the bridge pickup... unless the bridge pup is much hotter . [As indeed it is with Standard Epi Les Paul models ;^)].

The strings move with much greater amplitude over the neck pup...hence more signal. [it's just the same as there being more signal if you hit the strings harder ;^) ]

[L_Mo]

Ok, so I guess maybe I'm just being too picky about all this. I've been playing awhile, and while I played electric in jazz band in highschool, I didn't mess much with trying to get different tones. So perhaps I just expected something. Anyway, maybe you guys can tell me if I'm just being picky?

 

So I made a recording, you can find here: http://www.supload.com/listen?s=Q2XSAKG0SFFJ

I tried balancing the pickup volume as quantitatively as I could (looked at input level on amp and tried to adjust to be the same).

 

The recording is all one track, 3 takes. Played through a Hiwatt DR-103 simulator on clean, so you can hear every little mistake (ew).

 

There are 8 things on the track, in this order:

 

A short chunk of a tune:

1) Bridge, tone up

2) Neck, tone up

 

Short riff for comparing different settings:

3) Bridge, tone down

4) Bridge, tone up

5) Bridge, tone up + coil tap

6) Neck, tone down

7) Neck, tone up

8) Neck, tone up + coil tap

 

As you can probably notice, I just learned Blue Monk yesterday, so while the notes are there, I more or less murdered it... I also discovered that I can't keep time. I recorded that bit through the neck less than 10 seconds after the bridge and somehow totally lost the beat. Shoulda turned on the metronome B)