How to get more high end in a P-90?

[belwar]

So i've got my first P-90's wound and overall i'm pretty happy with them, I would like to get some more high end out of them though. A little more sparkle in the upper notes if you know what I mean... I'm still pretty new at this and would love some help.. Here's my specs:

A5 magnets
No Keeper Bar (poles right against magnet)
42 AWG poly solderable
1/4" Internal Bobbin height
3/4" Filister head screws.
Rapid traversing scaterwound. Aprox 15-20 TPL.
10000 turns.

Im currently winding the core at relatively tight tension, then loosening it as I get to about 5000 winds to keep the bobbin from flaring.

I'm assuming the biggest alteration in tone is going to come from tension in the wire. Any thoughts on what I need to do to achieve my goal?

b.

[Norcal_GIT_r]

Try more tpl. 15-20 is pretty wide.

[John_H]

What are you using for a test guitar? The pickups might be plenty bright. What are the values of the pots, and capacitor?

[belwar]

What are you using for a test guitar? The pickups might be plenty bright. What are the values of the pots, and capacitor?

South American Mahogany les paul jr'ish guitar in the neck position. 500k RS superpots. 0.014 PIO caps.

[John_H]

South American Mahogany les paul jr'ish guitar in the neck position. 500k RS superpots. 0.014 PIO caps.

Try swapping the cap with different values. In my Jr I've got a .033 cap, and a 1m tone pot.

[belwar]

While I understand how cap values and tone pot values can alter the treble, im more talking about altering the windings, as the average person who buys them is likely going to have 22's and 500k's. That would work to brighten up an individual set, I want to brighten up every set

[John_H]

While I understand how cap values and tone pot values can alter the treble, im more talking about altering the windings, as the average person who buys them is likely going to have 22's and 500k's. That would work to brighten up an individual set, I want to brighten up every set

Gotcha; I'd try fewer turns, and less scatter for starters. You could experiment by stripping a few hundred turns off of one and comparing it. It might help, especially in the neck position.

[David Schwab]

Try using a keeper bar. That will bring up the inductance and lower the resonant peak, which should give you a nice upper mid peak, which brightens up the tone.

The older P-90's from the 50's - 60's has less wire on them too (around 8k), so they had less mids and more of a Stratish tone, just fatter.

[GlennW]

The older P-90's from the 50's - 60's has less wire on them too (around 8k), so they had less mids and more of a Stratish tone, just fatter.

By "8k", do you mean 8,000 turns? I thought the old ones were about 8K resistance with 10,000 turns.

[David Schwab]

By "8k", do you mean 8,000 turns? I thought the old ones were about 8K resistance with 10,000 turns.

8K resistance. I don't know how many turns, but I had an old ES-330TD with dogears that were about 8K. Then I had some P-90's from a 70's SG, and they were about 9K and sounded a lot different. More midrange.

I liked the ES-330's neck pickup tone, so I took one of the SG's pickups and unwound about 1,000 turns and used it in the neck position on a Les Paul copy I had (along with a patent label humbucker at the bridge).

These were all readings I did with an analog VOM, so who knows how accurate they were.

[David King]

If there's any room on the bobbin for a thicker insulated wire then that should help too. You might even get away with thicker insulation on the next thinner AWG if you don't have the room but I wouldn't know that for sure.

[GlennW]

...so I took one of the SG's pickups and unwound about 1,000 turns...

I might try that. The pair I have is supposedly from a 2007 SG and they read about 8.35-8.4K. Do you that .5K will make a noticeable difference? Mine hooked to 500K pots and .022uF polyester OD's.

I think I read hear where Possum said some of his were under 8K and somone commented on how clear they sounded.

[Mark Hammer]

10,000 turns on a P90 bobbin? I have no idea how that could be bright-sounding. Keep in mind that each of those turns has a much wider circumference than on a tall-n-thin Strat bobbin. So, by the time you've got 10,000 turns on, you are likely to have much more than 8k DCR.

[kevinT]

As mentioned, more turns per layer and loosen the tension a bit.

I would also try different fillister pole pieces. I have about 11 different fillister screws from various sources and they all sound different. Some are darker and don't do much to enhance the tone and some are brighter and add a lot of sparkle.

[Mike Sulzer]

I would like to get some more high end out of them though.

P 90s have a pretty low resonant frequency. Strat pickups have a high resonant frequency; they sparkle. (http://www.seymourduncan.com/comparetones has the resonant frequencies of all of Duncan's pickups.)

Changing the cap in the tone control will not give you more brightness. The cap is out of the circuit when the control is on 10. Using a large tone pot increases the Q and makes it sound brighter, up to a point, but if the resonant frequency is low, it cannot help very much.

Increasing the inductance still more will lower the resonant frequency. If the frequency is low this will give you even less high end. Only if the resonance is very high (above the response of the guitar) will lowering it (into the range of the guitar) give more highs.

If you want to raise the resonant frequency, you use fewer turns on the pickup. That works every time.

[David Schwab]

The cap is out of the circuit when the control is on 10.

No, the cap is in the circuit all the time, but on ten has the value of the pot between it and ground.

But you can hear the difference, or else the Fender TBX tone controls wouldn't work.

I agree that winding the P-90 will less turns will do the trick, as I mentioned I did this in the past. Works nicely.

[kevinT]

+1 on using fewer turns. However, if you decide to stay with traditional p90 specs, you'll have to tinker with other things to coax the sparkle out of the pickup. ;)

[David Schwab]

Right, plus if you push the resonant frequency too high, it actually doesn't sound as bright, but more acoustic like. You just have to fiddle about until you hit the right mark (or figure out way to model the response, which sounds nice in theory).

Wire gauge can have a big impact as well.

[Mike Sulzer]

To be more precise on the effect on brightness of changing the value of the capacitor in the tone circuit: when the tone control is on 10, its resistance is much larger than the magnitude of the impedance of the capacitor at high frequencies. The capacitor acts almost like a short circuit, and so its exact value (when the pot is on 10) is not an issue. In that sense, that is, behaving as a short circuit, it is not in the circuit, but could be replaced with a piece of wire. The pot, however, loads the pickup just like any other resistor placed across the pickup, decreasing brightness. As the pot is turned down from 10, the resistance decreases, and cuts the brightness still further. The capacitor plays a dominant role when the pot is closer to zero, preventing the low frequencies from being shorted out. Sorry about the confusion.

[Zhangliqun]

Try using a keeper bar. That will bring up the inductance and lower the resonant peak, which should give you a nice upper mid peak, which brightens up the tone.

I disagree. In my experience the keeper bar makes it smoother and darker. Removing it helpeld a lot toward de-mudding my neck pu's. I agree that dropping the number of turns will help. Something else that will help is using narrower bar magnets, about 3/8" wide instead of 1/2".

[David Schwab]

I disagree. In my experience the keeper bar makes it smoother and darker. Removing it helpeld a lot toward de-mudding my neck pu's. I agree that dropping the number of turns will help. Something else that will help is using narrower bar magnets, about 3/8" wide instead of 1/2".

That's true. Higher inductance works better with fewer winds.

My idea was if the resonant peak was too high, that would bring it down. That worked really well for me with my latest bass pickups.

It's all a balance.

[madialex]

I would also say back off the tension a little, this will brighten them up as well.

[black_labb]

re the resonant frequency, if one were to remove the bass plate to increase the resonant frequency, and then put more winds to get closer to the original resonant frequency, how similar would the pickup be tonally? im thinking that this would be a good way to get a higher output p90 with a simililar tone to a traditional p90.

[Possum]

no one has mentioned that if you use ceramic magnets that will brighten it up considerably, removing all that metal in the alnico is why.....

[Gtr_tech]

Using alnico rod magnets instead of the bar magnet and screw poles will sure brighten one up. I like'em that way for the neck pos.

[bbsailor]

To obtain more brightness or high end out of a P90 or any pickup, use a buffer to isolate the pickups from the capacitance loading of the guitar cable which adds about 30pf per foot. See this web site to build a buffer cable which puts the active FET in the guitar-end plug and requires no modifications of your guitar. http://www.till.com/articles/PreampCable/index.html

Joseph Rogowski