Problem with EMG 89 and 58, works but something is not right?

[Izzyprad]

Hello all forum members,

I stumbled on this forum while I was trying to solve the problem with my EMG 89 and EMG 58 pickups with 1 volume (split coil), 1 tone, 3 way toggle, which I was trying to install on my ESP LTD M200 UC guitar. Looks like there are lots of knowledgeable people here in this forum, so I thought I might post a question here.

I have soldered everything as per the diagram shown below. The good thing is the pickups are working. Toggle switch works fine, volume control works fine, tone also works fine but really not noticeable.

I have followed the wiring diagram from the EMG website, i.e.
http://www.emginc.com/content/wiring...MG-81TW-89.pdf
(The middle diagram in Pg 3)

But, my problem is I don't get enough sustain, after certain volume level the signal dies suddenly??? As if there is some noise gate. Another strange thing is I can still play with volume all way down, although not enough gain. Something is wrong, I don't know what. Also there is some noticeable amount of hum. One thing I have noticed is, from the EMG wiring diagram, they have connected the volume pot in a different way. I know it will work but does not make sense.

I have wired few passive pickups before and never had any problem. This is my first time wiring an Active pickup, so may be I am missing something here. And yes, I have connected a new battery and both volume and pot are 25k.

I am an electrical engineer (recent graduate) myself. So I believe I have done all the wirings correctly. Please let me know if am missing anything here.


I would really appreciate if someone can shed some light here.

[bbsailor]

Originally Posted by Izzyprad

Hello all forum members,

I stumbled on this forum while I was trying to solve the problem with my EMG 89 and EMG 58 pickups with 1 volume (split coil), 1 tone, 3 way toggle, which I was trying to install on my ESP LTD M200 UC guitar. Looks like there are lots of knowledgeable people here in this forum, so I thought I might post a question here.

I have soldered everything as per the diagram shown below. The good thing is the pickups are working. Toggle switch works fine, volume control works fine, tone also works fine but really not noticeable.

I have followed the wiring diagram from the EMG website, i.e.
http://www.emginc.com/content/wiring...MG-81TW-89.pdf
(The middle diagram in Pg 3)

But, my problem is I don't get enough sustain, after certain volume level the signal dies suddenly??? As if there is some noise gate. Another strange thing is I can still play with volume all way down, although not enough gain. Something is wrong, I don't know what. Also there is some noticeable amount of hum. One thing I have noticed is, from the EMG wiring diagram, they have connected the volume pot in a different way. I know it will work but does not make sense.

I have wired few passive pickups before and never had any problem. This is my first time wiring an Active pickup, so may be I am missing something here. And yes, I have connected a new battery and both volume and pot are 25k.

I am an electrical engineer (recent graduate) myself. So I believe I have done all the wirings correctly. Please let me know if am missing anything here.


I would really appreciate if someone can shed some light here.

Izzyprad,

Make sure that you are using a stereo tip, ring sleeve jack. The battery is turned on when the mono guitar cable plug shorts the ring to the sleeve and completes the battery ground circuit.

Joseph Rogowski

[Izzyprad]

Yes sir, I am using TRS jack.

Just now I tried hooking up the pickup hot wire straight to the Tip of the input jack, and it sounds fine.

So something is not right. Is that wiring diagram shown in EMG's pdf file right? I mean the Tip of the input jack is connected to the sid eof the volume Pot. Shouldn't it be connected to the middle lug of the pot?

[bbsailor]

Originally Posted by Izzyprad

Yes sir, I am using TRS jack.

Just now I tried hooking up the pickup hot wire straight to the Tip of the input jack, and it sounds fine.

So something is not right. Is that wiring diagram shown in EMG's pdf file right? I mean the Tip of the input jack is connected to the sid eof the volume Pot. Shouldn't it be connected to the middle lug of the pot?

Izzyprad,

The normal pot wiring is to put the pot outer luds across the pickup leads and take the output from that pot from the center lug. This puts a constant load on the pickup. However if you have two volume pots, when the selector is set for both pickups, this wiring arrangement causes both pickups volume to interact when either volume control is used.

The alternate way is to connect the pickup on the the outside and center pot lugs and then take the output off the other outer lug. When two volume pot are wired this way, there is independent volume control of each pickup even when the selector switch is set for both pickups being on. With this wiring arrangement you can use the volume controls to mix the output of each pickup when used together.

Since you are only using one volume pot, you can use the traditional method with the pickup leads on the outer pot lugs and take the output from the center lug. If you want to have independent control of each pickup you can try to locate a stacked audio concentric pot with a 25K to 50K value and take the output off the side lugs to have individual control of the pickups when both are used together. This way you don't need to drill any additional holes.

Edit: Use the procedure below for passive pickups. This will not work on active pickups as the pickups are buffered by active electronics. Sorry for possibly confusing you.

When using active pickups test the pickup wiring by hooking the guitar to an amp and use a small metal rod like a ferrous screwdriver or nail to tap the pickup to check that both coils are working in the humbucking mode and that only one coil is working when you split the pickup.

Passive pickups: Use an ohm meter and take readings from the jack output to the guitar cable contacts and record the resistance in all switching combinations and see if that matches the resistance of each individual pickup winding. Splitting series coils will make the pickup output resistance about half. Putting two coils in parallel will also make the resistance about half assuming that the pots are on full volume. Since you know electronics you can enter the resistance readings on the schematic to verify that your wiring is correct in each switch combination: single coil full, single coil split, both coils full and both coils split.

I hope this helps.

Joseph Rogowski

[David Schwab]

What kind of jack are you using? If it's a barrel (panel) jack, check the contacts with the meter. Sometimes they are not the ones you think, and the jack gets miswired.

[Izzyprad]

Thanks for your help!

I rewired, and connected the tip of the input jack to the middle lug of the pot and connected the output from the pickups to the other two lugs of the pot. Then I disconnected the tone control. And it 's working now.

The problem seems to be the tone control for some reason. I did check the pot and the cap, and both seems to work fine, but don't know why if I connect the tone circuit, it sounds gain/sustian is reduced.

So I will have to do some research, I guess.

If you ignore everything before the switch, I have volume and tone control setup as below (although tone is disconnected for now):

[David Schwab]

You aren't wiring the tone control across the switch, are you? It almost looks like that on the schematic.

Try wiring thew tone control up as it is on the EMG instructions and see what you get.