What kind of Pots for a P90

[Doughboy]

I have a set of Fralin Noiseless P90s. What value pots would be best for this? I'd say 250k, since they're still single coils technically.

 

[Nando Vallart]

Gibson uses 500K

 

[bbl4ck]

I used 500K on my Firebird w/ P-90's neck/bridge and a Firebird middle.  I like em' just fine...
:rock-on:

 

[Cagey]

I'd use 500K parts, with a .022mf filter cap for the tone pot. You use P90s is for their unique tone, so you don't want to load them down or bleed them too much.

 

[Doughboy]

I'd use 500K parts, with a .022mf filter cap for the tone pot. You use P90s is for their unique tone, so you don't want to load them down or bleed them too much.

What function does the .022mf filter cap for the tone pot do?

 

[JaySwear]

used a 500k for my dimarzio virtual p90. love the sound!

 

[Cagey]

I'd use 500K parts, with a .022mf filter cap for the tone pot. You use P90s is for their unique tone, so you don't want to load them down or bleed them too much.

What function does the .022mf filter cap for the tone pot do?

It allows you to gradually roll off the highs. Some people use .033mf or .047mf, but they're a bit extreme in my estimation. The larger the cap, the earlier and more dramatically it bleeds the highs to ground, and vice versa. Some people believe the construction of the cap makes a difference, but that's mostly mental masturbation. .022mf is .022mf, whether you use air, paper, oil, mica, polystyrene, mylar or birdschitte as a dielectric. The advantages of different dielectrics is their dielectric strength vs. thickness, so you can use them in higher voltage circuits where you need prevent the cap from shorting out. It changes their size pretty dramatically, too.

For instance, this a .022mf 1000vdc paper/oil cap...

this is a .022mf 200vdc polystyrene cap...

this is a .022mf 600vdc mylar cap...

these are ceramic caps...

Since guitar pickups only generate voltages in the millivolt range, any of these will work fine and they'll all sound the same if they're actually .022mf caps. But, caps are notoriously sloppy devices, so their values vary quite a bit even within the same production run. Because of the power of suggestion that says a higher price makes for a "better" device, this gives people the impression that a $12 .022mf 1000 wvdc paper over oil Vitamin Q cap sounds "better" than a $.50 cent .022mf 150 volt ceramic disc. Chances are, neither of them are really .022mf, and they're almost certainly not identical to each other. You look up any physics formula regarding capacitive reactance, and there's no place to insert a variable for dielectric strength, or "working voltage". That's the last consideration an engineer makes, and it's based on what kind of voltage a circuit is expected to see, not how it's going to behave in a circuit. Then the purchasing agent for the company buys whatever the least expensive part is he can get that meets at least that spec. Nobody cares, except the marketing weenies who might advertise a particular type of part for an audience who doesn't know any better.

 

[Doughboy]

Thanks for the detailed response Cagey.

I'm going to put in some .022mf filter caps on Monday.  :icon_thumright:

 

[Jusatele]

I'd use 500K parts, with a .022mf filter cap for the tone pot. You use P90s is for their unique tone, so you don't want to load them down or bleed them too much.

What function does the .022mf filter cap for the tone pot do?

It allows you to gradually roll off the highs. Some people use .033mf or .047mf, but they're a bit extreme in my estimation. The larger the cap, the earlier and more dramatically it bleeds the highs to ground, and vice versa. Some people believe the construction of the cap makes a difference, but that's mostly mental masturbation. .022mf is .022mf, whether you use air, paper, oil, mica, polystyrene, mylar or birdschitte as a dielectric. The advantages of different dielectrics is their dielectric strength vs. thickness, so you can use them in higher voltage circuits where you need prevent the cap from shorting out. It changes their size pretty dramatically, too.

For instance, this a .022mf 1000vdc paper/oil cap...

this is a .022mf 200vdc polystyrene cap...

this is a .022mf 600vdc mylar cap...

these are ceramic caps...

Since guitar pickups only generate voltages in the millivolt range, any of these will work fine and they'll all sound the same if they're actually .022mf caps. But, caps are notoriously sloppy devices, so their values vary quite a bit even within the same production run. Because of the power of suggestion that says a higher price makes for a "better" device, this gives people the impression that a $12 .022mf 1000 wvdc paper over oil Vitamin Q cap sounds "better" than a $.50 cent .022mf 150 volt ceramic disc. Chances are, neither of them are really .022mf, and they're almost certainly not identical to each other. You look up any physics formula regarding capacitive reactance, and there's no place to insert a variable for dielectric strength, or "working voltage". That's the last consideration an engineer makes, and it's based on what kind of voltage a circuit is expected to see, not how it's going to behave in a circuit. Then the purchasing agent for the company buys whatever the least expensive part is he can get that meets at least that spec. Nobody cares, except the marketing weenies who might advertise a particular type of part for an audience who doesn't know any better.

Great post, I am an electrician and do not think I could have put it so strait forward
I know Gibson used 500 pots all during the P90 Days So I stick with them, However, if you do not know, ask the company winding the pickups as they will know best about their product.

 

[Super Turbo Deluxe Custom]

I have a set of Fralin Noiseless P90s. What value pots would be best for this? I'd say 250k, since they're still single coils technically.

"Noiseless" is usually code for dual coil construction, single coil sound.  In either case, go 500K because most dual coils and P-90s are that anyway, and this one may be both.  In a nutshell, it's just a brighter sounding pot.

 

[Firebird211]

I vote for the 500K ohm pots as well.  You will get a fuller sound than with the 250K, and if you want your tone like that, at least you can turn the 500K ohm pot's down to that level.

 

[rockskate4x]

I have a set of Fralin Noiseless P90s. What value pots would be best for this? I'd say 250k, since they're still single coils technically.

Fralin Noiseless P90's are actually humbuckers technically... that's how they are noiseless... In that case I always say 500k or higher...

 

[Jusatele]

the current fad in pickups is stacked humbuckers poising as single coils. They do cut 60 cycle hum but do not match the timbre of the single coils.
I think that, like the old amps guys go gaga about to get the sounds they want to record, the sound of single coils unique to them because of the way they are made, we will see a resurgence in the type soon enough, Live sound and studio sound is 2 different things.

 

[lafromla1]

Just bought a set of P-90's and the manufacturer suggested 250's for these specific ones.  Can't wait to hook 'em up and see what they sound like.