Help me in getting rid of bridge ice picking.

[studiostriver]

Hi to all.
I need advise how to get rid of ice pick tone I`m getting from bridge pickup.Its not too much in a tone,but its there.

Both pickups I installed sound wonderful,but maybe just little bit more high end then I expected.

I planning to switch .022 with 0.33uF cap...I think that will do the job.

But I wanna ask your opinions?
For instance,Ive heard that soldered a 1nF ceramic capacitor across the output of brige pickups can solve that ice picking problem.


Thanks in advance guys.
Best regards.

[newey]

I planning to switch .022 with 0.33uF cap...I think that will do the job.

Nope, that won't help. When your tone pot is at "10" (i.e., full clockwise) the tone cap is out of the circuit for all practical purposes. Changing the tone cap changes the frequency response of the control as you turn it down, it has no effect unless you move the knob away from "10".

You have three options here, one mechanical and two electronic. The easiest is the mechanical solution- turn down the tone control. Of course, if you move the knob, you're back to ice-pick territory. For a more permanent solution, you're looking at the electronic options.

First, as you suggest, is a capacitor. Whether 1nf is a good value may depend on what your ears like, and depend upon the specific pickups as well. Some experimentation may be in order to decide on a good value. You can do the testing external to the guitar, allowing for easy swapping of caps, or if you want to get fancy, you can build a "cap substitution box" with a number of different values to test, this allows you to easily do A/B comparisons of different values.

The second option is to change pot values to a lower resistance. You can change to a lower value for just one of the pots, or change both pots for more treble reduction. However, if the guitar has more than one pickup and if the V and T pots are master volume and tone, then changing pot values won't just affect the bridge pickup, but all pickups- and you may not want to affect the tone of the other pickup(s).

[studiostriver]

Nov 18, 2015 22:20:02 GMT -5 newey said:

I planning to switch .022 with 0.33uF cap...I think that will do the job.

Nope, that won't help. When your tone pot is at "10" (i.e., full clockwise) the tone cap is out of the circuit for all practical purposes. Changing the tone cap changes the frequency response of the control as you turn it down, it has no effect unless you move the knob away from "10".

You have three options here, one mechanical and two electronic. The easiest is the mechanical solution- turn down the tone control. Of course, if you move the knob, you're back to ice-pick territory. For a more permanent solution, you're looking at the electronic options.

First, as you suggest, is a capacitor. Whether 1nf is a good value may depend on what your ears like, and depend upon the specific pickups as well. Some experimentation may be in order to decide on a good value. You can do the testing external to the guitar, allowing for easy swapping of caps, or if you want to get fancy, you can build a "cap substitution box" with a number of different values to test, this allows you to easily do A/B comparisons of different values.

The second option is to change pot values to a lower resistance. You can change to a lower value for just one of the pots, or change both pots for more treble reduction. However, if the guitar has more than one pickup and if the V and T pots are master volume and tone, then changing pot values won't just affect the bridge pickup, but all pickups- and you may not want to affect the tone of the other pickup(s).

Hi,thanks for answering,
So sad that first option wont do anything.But to be honest I find few You Tube videos when one guy is actually make that box for testing caps but just for tone.And some of them sounded very different even at 10.

I could live with using tone pot.Cause its not too much ice pick,just a little bit.

For first option,what capacitators values would be good deal with in order to test?

Changing another pots is not possible in my case,since only 250/300 and 500k existed with push pull...300 would be way too dark. I need just little bit darker tone.Something like 450k would suit my needs,and that things do not exist I think.

[cynical1]

One quick question: What are the pickups you're using?

HTC1

[studiostriver]

Nov 19, 2015 0:16:47 GMT -5 cynical1 said:

One quick question: What are the pickups you're using?

HTC1

They are custom made by my specifications.The pickups actually sound and behave wonderfully as I stated above.He pretty much hit the spot on everything,except the high end should be about 10% lower on both pickups,and just maybe on a bridge that ice pick frequency which watching from spectrum analyzer in my DAW is centered at 3khz. Scooping that place on eq giving me less ice pick.

[cynical1]

The reason I asked about the pickups is that a lower output pickup may suffer from this more than a high output pickup. Playing with the bridge pickup height may help. To preface, as a lad I was taught two nickels on the low side and one nickel for the high side...and tweak to taste. For reference, a nickel is approximately 1.95mm

Or, you could just drop the tone on the bridge pickup. As far a cap value, I normally use dark caps on my bridge tone. We're in the .56 to .68 range...which I usually run between 5-7.

But that's me...too many years as a bass player...

HTC1

[studiostriver]

Nov 19, 2015 2:38:00 GMT -5 cynical1 said:

The reason I asked about the pickups is that a lower output pickup may suffer from this more than a high output pickup. Playing with the bridge pickup height may help. To preface, as a lad I was taught two nickels on the low side and one nickel for the high side...and tweak to taste. For reference, a nickel is approximately 1.95mm

Or, you could just drop the tone on the bridge pickup. As far a cap value, I normally use dark caps on my bridge tone. We're in the .56 to .68 range...which I usually run between 5-7.

But that's me...too many years as a bass player...

HTC1

I will start to play with height today.Pickups was set to pretty low,that was original height of previous pickup.I will try to raise height,and observe changes and see what will come of it.

[reTrEaD]

Nov 18, 2015 18:49:47 GMT -5 studiostriver said:

For instance,Ive heard that soldered a 1nF ceramic capacitor across the output of brige pickups can solve that ice picking problem.

Certainly worth trying. I seem to recall someone using a very small capacitor directly in parallel to make a pickup slightly brighter, but I think the value was less than 1nF.

Nov 18, 2015 23:10:27 GMT -5 studiostriver said:

Changing another pots is not possible in my case,since only 250/300 and 500k existed with push pull...300 would be way too dark. I need just little bit darker tone.Something like 450k would suit my needs,and that things do not exist I think.

I think you may be over-estimating the effect of resistive loading on tone. If you would like to do a rather simple experiment, bridge the connections between the wiper and clockwise end of your volume control. This will allow you to change the resistive load without actually changing the "volume" because it's no longer acting as a voltage divider. If you find a setting that gets rid of the brittle "ice-pick", make a note of the position on the dial. Then disconnect and measure the resistance of the pot at that setting.

You can then calculate the value of a resistor to put in parallel with either the volume pot (to affect either pickup) or directly in parallel with the bridge pickup.

[studiostriver]

This JP7 had direct mount and original pickups height didn`t work at all,even slightly pushing it back with surgical tube in screws..After I added sponge and get them to high level all harsness`s gone..

I will do some recording tests,but I think the difference is night and day.

Know its somewhat 2.4 bridge,and 3mm neck... Original postitons were way too low 5/6mm for both pickups.

I was a fool.All harsh frequencies disappear.
It added warm tone with lots of sustain.Plus adjusting screws pickups itself for 7 and 6 string I get more attack and even warmer tone.

Pickups are know awesome.


All those years in playing guitars and yes what a noob I am. Adjust height was the first thing I should experiment with for days till I find sweet spot.

[cynical1]

Forgot the other part of the nickel thing...CRS... You have to finger or capo your highest fret, get the coins snug and lower the sides of the pickup until the coin(s) fall out. I'm fine. Back on my meds again...

HTC1

[tubejockey]

Sounds like the OP got it sorted out, but I will add one more thing to the conversation.  Even with the tone pot on 10, the cap still has an effect on the resonant frequency, assuming you don't have 5Megohm pots or something.  My favorite solution is to use a 500k audio pot with a .0068uF to .01uF cap.  In this configuration, the tone will actually get brighter, but you have much more control.  As you roll down the tone, you blunt the icepick gradually down to about 6.  Then the resonant freq becomes more apparent, reshaping the high end into a snarlier, rounder tone.  The mids stay unmolested.  The tone control becomes usable throughout its entire range.  I can roll it all the way down and make my stat bridge growl like an old tele.

[reTrEaD]

Oct 13, 2018 21:34:08 GMT -5 tubejockey said:

Sounds like the OP got it sorted out, but I will add one more thing to the conversation.  Even with the tone pot on 10, the cap still has an effect on the resonant frequency, assuming you don't have 5Megohm pots or something.  My favorite solution is to use a 500k audio pot with a .0068uF to .01uF cap.  In this configuration, the tone will actually get brighter, but you have much more control.  As you roll down the tone, you blunt the icepick gradually down to about 6.  Then the resonant freq becomes more apparent, reshaping the high end into a snarlier, rounder tone.  The mids stay unmolested.  The tone control becomes usable throughout its entire range.  I can roll it all the way down and make my stat bridge growl like an old tele.

Hello tubejockey

Welcome to the GuitarNutz family!

I've enjoyed reading your posts so far.  I'd like to respectfully disagree with one statement in that post.

While it will have 'an effect' the effect will be so small we can (and should) consider it insignificant. We have four parallel paths loading the pickup. The treble-cut tone control, the volume control (when on ten, we can just refer to the total resistance), the amplifier impedance, and the cable capacitance. For modeling purposes, we generally calculate that as a resistance of 200k in parallel with a capacitance of 500pF.

Even at a low frequency such as 100Hz, the .01uF capacitor you mentioned will only have an X_c of 159k. Added (trig is our friend here) to the 500k resistance of the tone pot nets us a total impedance of 524.7k. Not terribly different than a 500k resistor, although the phase angle isn't purely resistive. And remember, this is in parallel with the 500k volume pot and 1meg amplifier impedance. 

As we move up in frequency a decade to 1000Hz, the total impedance of the tone-cut path is 500.25k.
At 10,000Hz, 500.003k.

---

When we move into a region where X_c is equal to or greater than the resistance in series with it, our choice of value for the tone cap becomes very important. Until then, not-so-much.