What pots to use with active emg humbuckers? (25/250/500k)

#1
Hi,

I'm replacing the pots on my new LTD Snakebyte it has neck and bridge volume pots; I believe they are wired between the pickups and the ABY switch; there's no master volume nor tone pots.

I measured the bridge volume pot on my LTD Snakebyte, and it seems to be 17.5Kohm.
I measured the bridge volume pot on my LTD F-Series, and it seems to be 25Kohm. (this is the one from the EMG Solderless Kit)

Both guitars have EMG HET SET Active Pickups.

I want to put push/pull pot on the bridge postition so I can fully disconnect the battery from both positive and negative sides to prevent it draining when unplugged... I had this problem on my F-Series and a positive side latch switch fixed it.

So the questions I have are.

1. Does it matter what the resistance of the pot is? 25k / 250k / 500k - I've seen wiring diagrammes with all 3 being used.
2. Should I use log pots or linear pots?
3. Should I wire the pots as (IN OUT GND) or (OUT IN GND) IN will be from the humbuckers and OUT will be going to the ABY switch.
4. Can I do something to remove this buzz/hiss when the volume pots are at zero?
5. When the battery is fully disconnected, should I put the +9V (red) of the humbuckers to ground or leave them floating? if grounded will it need a resistor? if so what value?
 
#2
As far as I know actives use lower K pots. The EMGs which would be factory installed in my LTD Viper used 25K pots. I bought it from it’s owner that had fitted new Seymours instead of the EMGs, but he didn’t fit the correct pots, hence piss poor tone. Single coils typically use 250K to keep the treble spike down and Humbuckers typically use 500K or even 1 Meg ones because they tend to up the treble and down the mud. My Lester Standard has factory fitted 300K pots which were quite difficult to get used to with it’s original Humbuckers. The PX100s I have in it now work wonders. I am far too incapable to explain the science. I’ve always read up and understood it by Google searching. I get the basic idea now but typically have to search again everytime I want to change wiring again... :p

As for Log or Lin. I understand that Log is more commonly suggested for volume because the hearing does not work linear but more like logarhythmic. I have always follow with Log pots for my volume.

I think the buzz at zero volume might indicate a ground that hasn’t been wired in properly or not even wired at all.
 
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#3
Alright, 25K push/pull pot arrived... It's perfect for what I want in every way!

Except.... the thread size is 9.5 mm and the installed ones are 8mm; and the hole in the guitar is like 8.3mm.
I'm not drilling out the hole, I've seen what happens to the finish when people have tried.

I might have to order one from EMG; the electrical diagramme of the PCB on the EMG push/pull pot though is making my head spin.
 

Tankman

Subtly not giving a F*ck
#4
Alright, 25K push/pull pot arrived... It's perfect for what I want in every way!

Except.... the thread size is 9.5 mm and the installed ones are 8mm; and the hole in the guitar is like 8.3mm.
I'm not drilling out the hole, I've seen what happens to the finish when people have tried.

I might have to order one from EMG; the electrical diagramme of the PCB on the EMG push/pull pot though is making my head spin.
Actually, just find a starting point (the pickup usually) and go from there. Even I can follow an EMG solderless diagram, and I suck at electronics.
 
#5
Alright I think I worked out this blasted wiring diagramme and how to make the switch put the battery into and out of the circuit. Had to look at all of the examples to work out how H1 to H6 were wired up...
If you want add a bridge tone pot, plug it in parallel on H2.





Edit: Alright, EMG Solderless push/pull pickup kit ordered... just have to wait a week now for FEDEX haha
Edit2: Pins are confirmed.
Edit3: Added External +18V Power from TRS (ring)
Edit4: the bottom push/pull switch is inverted... who knew!
 
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Chu

Well-Known Member
#6
I used a hand reamer on my very pretty USA PRS to enlarge the hole to fit a toggle switch in place of the silly rotary pot/switch. Terrifying but without incident!

I've since used it on another guitar or two with increasing confidence and still no issues!
 

SemiCullen

Still haven't got the hang of Thursdays
#7
I used a hand reamer on my very pretty USA PRS to enlarge the hole to fit a toggle switch in place of the silly rotary pot/switch. Terrifying but without incident!

I've since used it on another guitar or two with increasing confidence and still no issues!
I have also done this with good results.
 
#8
I found out today that EMG do a 18V battery box that plugs in to the RING part of the socket on the guitar - giving the pickups more headroom (the HET Bridge pickup clips out of the box).

So if I run RING to the BLUE wire on pin 4 then I can power the pickups externally with the battery fully disconnected.
And if the pot is pulled then BLUE will be disconnected and it can be used normally from the internal battery.

I'm liking this idea more and more :dance:
 
#9
The thing arrived today! The pots are the right size for the holes and I spent about an hour going through all the pins to make sure that it's wired how I think it is... Except for one of the pot latches being inverted being upside down, I was spot on. Now all I need is a new set of strings and I'm ready to void the warranty haha
 

Magnus Pym

Grudges rot the soul
#10
I found out today that EMG do a 18V battery box that plugs in to the RING part of the socket on the guitar - giving the pickups more headroom (the HET Bridge pickup clips out of the box).

So if I run RING to the BLUE wire on pin 4 then I can power the pickups externally with the battery fully disconnected.
And if the pot is pulled then BLUE will be disconnected and it can be used normally from the internal battery.

I'm liking this idea more and more :dance:
This would also allow you to use rechargeable batteries with the usual low voltage problems
 
#11
Alright after two nights solid after work I've finally got it all wired in!
I haven't done that much soldering since secondary school ... but it's all done, tested with the volt meter and working perfectly!

I have a TS808 plugged into a 5150 - with all the gain and no noise gate.
If I touch the volume knob you can hear the vibrations of my fingers against it... but there's ZERO buzz/hum/noise.

So! I'm a very, very happy camper. :dance: and my battery wont drain all night long haha

Also locking tuner pegs OMG I love these!!
I am getting some for my other guitar!
 
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