50s single coil next to modern split P

[Fynn]

So I've been thinking about getting a bass with 50s P style single coil. However, I don't like any of the options on the market, and I would rather build an entirely new bass, before I buy one from a big brand.
However, a different thought just occured to me. As far as I'm concerned, the single coils p basses had their pickups closer to the neck, than the split coils right? What would maybe be the best way to go about installing another pickup on my current P bass, without having to remove the split one that's already in there?
I have an EMG with no active electronics in it right now. It simply has a passive tone knob and volume. But I would like to keep that EMG an EMG. I haven't found any single coils from EMG though. So would there be a way I could use a soldered pickup to connect to that very basic plug in EMG circuit?
I guess worst case scenario would be for me to add another whole circuit and maybe add a second jack? But I'm pretty sure atleast the pickup could somehow be frankenstein'd to the output jack with some solder, right?

I would really love to hear some input with this, as I would love to have a bass like that, where I can just switch between old single coil and modern split coil.

 

[Lo-E]

As far as pickup placement goes, a SCPB’s pickup is a little more than an inch closer to the neck than a split coil. If you butted it right up next to the split coil it wouldn’t be exactly in the right spot but it would be pretty close.

Active pickups typically sound better through lower value pots, either 25K, 50K or 100K while a SCPB pickup would sound better with 250K. You might want to consider running each pickup through its own, separate tone and volume pots and just place a simple selector switch at the output jack to choose between the two. That would be a lot more convenient than separate output jacks. You could still use a switching output jack for the power to the EMGs or you could use a 2-pole switch so that when you select the EMGs you would be applying power to them at the same time. You could do that anyway and still run it through the jack, that way assuring that you don’t drain the battery if you leave the EMGs selected, but you also don’t drain the battery when you’re using the SCPB. Lots of options….

 

[Fynn]

As far as pickup placement goes, a SCPB’s pickup is a little more than an inch closer to the neck than a split coil. If you butted it right up next to the split coil it wouldn’t be exactly in the right spot but it would be pretty close.

Active pickups typically sound better through lower value pots, either 25K, 50K or 100K while a SCPB pickup would sound better with 250K. You might want to consider running each pickup through its own, separate tone and volume pots and just place a simple selector switch at the output jack to choose between the two. That would be a lot more convenient than separate output jacks. You could still use a switching output jack for the power to the EMGs or you could use a 2-pole switch so that when you select the EMGs you would be applying power to them at the same time. You could do that anyway and still run it through the jack, that way assuring that you don’t drain the battery if you leave the EMGs selected, but you also don’t drain the battery when you’re using the SCPB. Lots of options….

I've seen pots with 250k are quite popular, but there are also some with 500k and some others. Is 250k like a standard, or does it depend more on what make and model of single coil it is? I've been looking at the Seymour Duncan SCPB-2.
I think an output switch sounds like a good idea. Though that would mean that I would have to splice open one of those EMG cables, correct? Because I don't think I can solder a new basic wire to EMG pots, since they have these very fiddly little prongs, which are meant for the EMG plugs.
If I were to just have the EMG be routed through a switch towards the end, and the new pickup too, so that I could select between them, would that mean the EMGs would drain even when they're just selected, and no lead is plugged in? I'm fine with unplugging all my basses after using them anyways, but if they drain just because I have that switch selected, that would be a bit of a bummer. I just assumed that wouldn't happen, aslong as there is no lead plugged in.

 

[Lo-E]

I've seen pots with 250k are quite popular, but there are also some with 500k and some others. Is 250k like a standard, or does it depend more on what make and model of single coil it is? I've been looking at the Seymour Duncan SCPB-2.
I think an output switch sounds like a good idea. Though that would mean that I would have to splice open one of those EMG cables, correct? Because I don't think I can solder a new basic wire to EMG pots, since they have these very fiddly little prongs, which are meant for the EMG plugs.
If I were to just have the EMG be routed through a switch towards the end, and the new pickup too, so that I could select between them, would that mean the EMGs would drain even when they're just selected, and no lead is plugged in? I'm fine with unplugging all my basses after using them anyways, but if they drain just because I have that switch selected, that would be a bit of a bummer. I just assumed that wouldn't happen, aslong as there is no lead plugged in.

The switch would go between the EMG circuit that exists now and the output jack. The battery power would still be going through the jack so the bass won't drain if it's not plugged in. In addition, you could also do what I suggested with a two-pole switch, disconnecting the power to the EMGs when the SCPB is selected. Either way, the bass won't drain when the cord is unplugged.

I don't know how familiar you are with circuits and switching but this is pretty simple stuff. If I have time I can try and draw up a digram for you, but I'm not sure when I'll have time.

Pot values are usually as much a matter of personal preference as they are anything else. The low impedance output from active pickups like EMGs will sound best with lower resistance pots like 25K, 50K or 100K. Which is best? It's kind of up to you. You will retain more treble as the value goes up. Most people will just use what the manufacturer recommends, and that's fine.

The same goes for passive circuits. 250K is pretty standard for SC pickups and 500K is pretty standard for humbuckers but there's no hard and fast rule. Treble will be retained in relation to the value increasing and you can easily use anything from 100K to 1M, depending upon what you like to hear. For a conventional circuit like a SCPB, most people will use 250K pots and a .05uF capacitor but you don't have to. Sometimes my decisions are based purely upon what I have in my parts drawer!

 

[Fynn]

The switch would go between the EMG circuit that exists now and the output jack. The battery power would still be going through the jack so the bass won't drain if it's not plugged in. In addition, you could also do what I suggested with a two-pole switch, disconnecting the power to the EMGs when the SCPB is selected. Either way, the bass won't drain when the cord is unplugged.

I don't know how familiar you are with circuits and switching but this is pretty simple stuff. If I have time I can try and draw up a digram for you, but I'm not sure when I'll have time.

Pot values are usually as much a matter of personal preference as they are anything else. The low impedance output from active pickups like EMGs will sound best with lower resistance pots like 25K, 50K or 100K. Which is best? It's kind of up to you. You will retain more treble as the value goes up. Most people will just use what the manufacturer recommends, and that's fine.

The same goes for passive circuits. 250K is pretty standard for SC pickups and 500K is pretty standard for humbuckers but there's no hard and fast rule. Treble will be retained in relation to the value increasing and you can easily use anything from 100K to 1M, depending upon what you like to hear. For a conventional circuit like a SCPB, most people will use 250K pots and a .05uF capacitor but you don't have to. Sometimes my decisions are based purely upon what I have in my parts drawer!

I am completely new to all of this stuff. I know how to solder on a basic level, and I roughly know what the insides of a soldered circuitry looks like.
I figured that the switch would need to go between the EMG circuit and the Output jack. My concern was about how I would go about connecting the EMG circuit to a switch. I've found a soldered switch, so I'm guessing I would have to take the cable that comes out of the EMG Tone control and splice that open, since that thing has a special little plug that goes onto the prongs of the tone control and then over the ones on the output jack.
I don't know what a 2 pole switch is. I've found a couple switches online, and pretty much all of them have 6 pins. I've found a diagram on how to wire them to they would make it switch between the one and the other pickup. Though now I'm wondering if a 3 way switch would maybe be a good idea. I'm not sure there's much use for a bass tone that is two different p bass configurations at the same time, but I might aswell have that option, if it doesn't mean I have to do too much extra work you know?
Beyond that, I would also probably have to add a grounding wire for that extra passive circuit, right? The EMG doesn't require one, so I didn't install one, but I already have the channel for a grounding wire underneath the bridge, so that wouldn't be too difficult I guess.
I think I'll do some more research, but I'm thankful for all the help I can get here!

 

[Lo-E]

I’ll see if I have time to draw something up for you tomorrow.

I don’t have a lot of familiarity with EMG’s plugging arrangements (and I dislike them for exactly this reason even though I know they make it easier for a lot of people) but I’ll try and help you suss it out.

The switch will go exactly where you say it will and yes, you’ll have to splice into the stock EMG wiring. The switch you’ll need is called a 2-pole, 2-position switch. A 3-way switch won’t help you here.