Wampler Pinnacle squeal

[Lbzg]

Hi,


Does someone knows how to fix squeal sound of gain pot (when boost or vintage switch is on and pot is on 2/3) in wampler pinnacle from guitar fx layouts?



Thanks,

[alexradium]

layout is very important in this type of circuit,wires have to be as short as possible,jfets should be sorted for the appropriate drain resistor not the other way around,use of a shielded cable could fix some issues,but most of all is good layout,sorry,no stripboard is ok for this application.

[Lbzg]

layout is very important in this type of circuit,wires have to be as short as possible,jfets should be sorted for the appropriate drain resistor not the other way around,use of a shielded cable could fix some issues,but most of all is good layout,sorry,no stripboard is ok for this application.

How short? And what way around? I have installed j201 as shown in layout...

Maybe did someone build this on that layout and fixed this issue...anyone?

[pappasmurfsharem]

layout is very important in this type of circuit,wires have to be as short as possible,jfets should be sorted for the appropriate drain resistor not the other way around,use of a shielded cable could fix some issues,but most of all is good layout,sorry,no stripboard is ok for this application.

How short? And what way around? I have installed j201 as shown in layout...

Maybe did someone build this on that layout and fixed this issue...anyone?

It's a common issue with that build. mine does the same thing.
apart from using shielded wire I'm not sure what you could try.

Also he meant you're supposed to sort through j201s to get the appropriate drain values as opposed to changing the drain resistor value

[Lbzg]

layout is very important in this type of circuit,wires have to be as short as possible,jfets should be sorted for the appropriate drain resistor not the other way around,use of a shielded cable could fix some issues,but most of all is good layout,sorry,no stripboard is ok for this application.

How short? And what way around? I have installed j201 as shown in layout...

Maybe did someone build this on that layout and fixed this issue...anyone?

It's a common issue with that build. mine does the same thing.
apart from using shielded wire I'm not sure what you could try.

Also he meant you're supposed to sort through j201s to get the appropriate drain values as opposed to changing the drain resistor value

OK. Thanks.

Kind of uncool if you ask me. :-(

By right drain value is it by trimmer or just put in another resistor and also how to calculate that resistor value?

[pappasmurfsharem]

layout is very important in this type of circuit,wires have to be as short as possible,jfets should be sorted for the appropriate drain resistor not the other way around,use of a shielded cable could fix some issues,but most of all is good layout,sorry,no stripboard is ok for this application.

How short? And what way around? I have installed j201 as shown in layout...

Maybe did someone build this on that layout and fixed this issue...anyone?

It's a common issue with that build. mine does the same thing.
apart from using shielded wire I'm not sure what you could try.

Also he meant you're supposed to sort through j201s to get the appropriate drain values as opposed to changing the drain resistor value

OK. Thanks.

Kind of uncool if you ask me. :-(

By right drain value is it by trimmer or just put in another resistor and also how to calculate that resistor value?

These are the voltage posted in "the other forum" from the real deal.

Drain / Gate
Q1 4.72 / 0
Q2 8.98 / 2.99
Q3 4.78 / 0
Q4 8.98 / 2.99
Q5 3.59 / -1.68
Q6 3.86 / 0
@9VDC input regulated all switches up and all pots full "10"

The 22k's connected to Q5 and Q6 can be adjusted to get the 3.59v and 3.86v respectively. You may need to adjust the others but since since Q2 and Q4 connect directly to the 9V source I don't think those would matter I'm not sure how you would adjust Q1 or Q3, you may not have too. I'm still a n00b to all this stuff

But really you would just jumper two legs of an appropriate value trimmer anything from 25-50k would probably work then put it in place of a 22k and adjust until you get those values on the drain. then you can put a similar value resistor there. The real question is. As you have built it apart from the squeal does it sound good too you?

If so I wouldn't mess with it and just get sheilded wire for the input/output wires maybe for the boost too. You might try to use shorter wires if applicable.

[Lbzg]

Thanks for reply.

My values are:

Q1 - D: 4.31 G: 0.00
Q2 - D: 8.11 G: 2.72
Q3 - D: 4.39 G: 0.01
Q4 - D: 8.12 G: 2.67
Q5 - D: 1.39 G: 0.00
Q6 - D: 2.42 G: 0.00


I really like this pedal it is best I have ever heard! Wish I can use all knobs to see its full potential. :-)

I will try with trimmers but can you tell me are trimmers for downsizing values or I can upgrade values to higher, because my values are below 3.59/3.89V ?

[pappasmurfsharem]

Thanks for reply.

My values are:

Q1 - D: 4.31 G: 0.00
Q2 - D: 8.11 G: 2.72
Q3 - D: 4.39 G: 0.01
Q4 - D: 8.12 G: 2.67
Q5 - D: 1.39 G: 0.00
Q6 - D: 2.42 G: 0.00


I really like this pedal it is best I have ever heard! Wish I can use all knobs to see its full potential. :-)

I will try with trimmers but can you tell me are trimmers for downsizing values or I can upgrade values to higher, because my values are below 3.59/3.89V ?

They will just act as variable resistors if you tie two of the legs together Either 1&2 or 2&3 either way works. it will probably need to go lower in value to bring the D voltages up.

So just pop out both resistors, put a single socket piece in each place where the legs were. Then use alligator clips or wire to put the trimmer in both locations. Then turn the trimmer until you hit though values. after you find the right spot, measure the resistance across the trimmer and put whatever value resistor is close in the original spots.

[Lbzg]

Thanks for helping me. I have put 10k trimmers on Q5 & Q6 and it worked!

One thing to have in mind if someone is gonna build this (we all should) - it is wire sensitive! Find right position and always (really no alternative) fix pcb inside with screws or something tight. Wires needs to be only long to connect everything (1 inch is ok to be off) and do not bend them too much. It will squeal instantly. Also put all pots to max and boost on to find right position, it is easy since it will squeal instantly on that positions, if it doesn't than you have one of the greatest pedals of all time. :-)

[pappasmurfsharem]

Thanks for helping me. I have put 10k trimmers on Q5 & Q6 and it worked!

One thing to have in mind if someone is gonna build this (we all should) - it is wire sensitive! Find right position and always (really no alternative) fix pcb inside with screws or something tight. Wires needs to be only long to connect everything (1 inch is ok to be off) and do not bend them too much. It will squeal instantly. Also put all pots to max and boost on to find right position, it is easy since it will squeal instantly on that positions, if it doesn't than you have one of the greatest pedals of all time. :-)

Did you sound change much after adjusting the voltages?

[Paul Marossy]

On any really high gain distortion pedal, lead dress can be very important - it can be the difference between it squealing on every setting and being usable on any setting.

There's one boutique pedal builder out there that makes these pedals with mega neat wiring, with everything at perfect 90 degree angles, etc. and has wires running for fairly long disances in parallel right next to eachother. And one day he was wondering on a forum why he was having a problem with oscillation. I told him it was because of his wiring, and it was.

[Lbzg]

Thanks for helping me. I have put 10k trimmers on Q5 & Q6 and it worked!

One thing to have in mind if someone is gonna build this (we all should) - it is wire sensitive! Find right position and always (really no alternative) fix pcb inside with screws or something tight. Wires needs to be only long to connect everything (1 inch is ok to be off) and do not bend them too much. It will squeal instantly. Also put all pots to max and boost on to find right position, it is easy since it will squeal instantly on that positions, if it doesn't than you have one of the greatest pedals of all time. :-)

Did you sound change much after adjusting the voltages?

No, not so that it would be noticeable, it only cleans it and stabilize it. No more high pitched sounds in background.

On wires, yes short as possible. Avoid curves and right angles as much you can. Just go straight as you can and never bend any of transistors or even caps. This thing is sensitive as you can't imagine it. :-) have fun with setup and you will be glad you did. best pedal E V E R ! :-)

[pappasmurfsharem]

Oh I built it months ago just curious how yours faired;)