# How to fix the LFO tick in the Sea Horse and Dark Rift



## Chuck D. Bones

I've found a simple circuit mod that gets rid of the LFO tick in the EQD Sea Machine (Sea Horse) and Space Spiral (Dark Rift).  It has been tested on both pedals.  It's the same mod for both pedals, only the ref designators are different.

*Sea Machine:*
Remove C19.
Connect a 10nF cap between pins 1 and 2 on IC4.  A small MLCC on the back side is a clean way to do it. 

*Space Spiral:*
Remove C30.
Connect a 10nF cap between pins 6 and 7 on IC5.  A small MLCC on the back side is a clean way to do it. 

In theory, a mod of this sort should also work on the Chaos Machine & BiPhase.  It requires more surgery on those two pedals and has not been tested (yet).


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## moonlightpedalbuilds

Sooo goood! You are the greatest Chuck!


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## Chuck D. Bones

I had help with the testing.


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## moonlightpedalbuilds

Confirmed fix for Sea Horse


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## dawson

That's awesome- thanks a lot!
I haven't started my Chaos Machine yet, but I'll be building it soon, so I can offer to help testing that one.  I'm no more than a "cowboy" with the circuitry, but I've got a nice multi-meter and I follow instructions.


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## Nostradoomus

I just sold my duophase... got an unboxed phase ii I could mess with though. I think I get the idea, will report back tonight.


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## cooder

Excellent! I'm keen to hear how this could work on the BiPhase as mine ticks a wee bit on higher settings! And great to know for the other circuits too of course! Thanks!


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## Cucurbitam0schata

Would anyone mind showing off a photo/schematic of your mods for the ticking? 

These might be obvious:
 - When you say "remove C19..." - remove the cap and leave the gap wide open? 
 - When you say "connect a 10 nF cap..." - is the only mod a MLCC cap soldered directly on the underbelly of the pcb, in between pins X and X?


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## Nostradoomus

On the Sea Horse yes leave it open, the circuit is completed with or without C19 there. Haven’t seen the dark rift schematic but I’m imagining the LFO section is similar. You could technically have the cap running on the top side of the board from pin 1 facing side of R24 over to the pin 2 end of R21 I think, but it’s much nicer looking and easier to just do it on the bottom of the board.


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## Robert

Nostradoomus said:


> Haven’t seen the dark rift schematic but I’m imagining the LFO section is similar.


Virtually identical.

Very grateful for the work you guys did here!   

These modifications will be worked into both PCBs in the upcoming weeks.  Both boards will be marked "Rev1.3" on the back to identify that the changes have been made.



cooder said:


> Excellent! I'm keen to hear how this could work on the BiPhase as mine ticks a wee bit on higher settings!



If your Duo-Phase ticks on the right side only (looking at the face of the enclosure) you might want to try rerouting the wire to the input jack.  It's prone to picking up LFO noise.   I've never known the other side to tick, and moving the wire has always cured the issue.    With that said, this is certainly a welcomed modification if it helps.


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## Nostradoomus

Well nuts to my plan of tinkering with my Phase II...it’s dead quiet as it stands. ?‍♂️


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## Nostradoomus

Robert said:


> Virtually identical.
> 
> Very grateful for the work you guys did here!
> 
> These modifications will be worked into both PCBs in the upcoming weeks.  Both boards will be marked "Rev1.3" on the back to identify that the changes have been made.



Very cool!

Also if you have discounted old revisions I’ll take some


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## Dali

Chuck D. Bones said:


> *Sea Machine:*
> Remove C19.
> Connect a 10nF cap between pins 1 and 2 on IC4.  A small MLCC on the back side is a clean way to do it.



Sorry to ask but is the "small MLCC" is actually the 10nF capacitor?

Anonymous Builders by numbers


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## Robert

Dali said:


> Sorry to ask but is the "small MLCC" is actually the 10nF capacitor?
> 
> Anonymous Builders by numbers



Yep, that's correct.


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## Bobbyd67

Chuck D. Bones said:


> I've found a simple circuit mod that gets rid of the LFO tick in the EQD Sea Machine (Sea Horse) and Space Spiral (Dark Rift).  It has been tested on both pedals.  It's the same mod for both pedals, only the ref designators are different.
> 
> *Sea Machine:*
> Remove C19.
> Connect a 10nF cap between pins 1 and 2 on IC4.  A small MLCC on the back side is a clean way to do it.
> 
> *Space Spiral:*
> Remove C30.
> Connect a 10nF cap between pins 6 and 7 on IC5.  A small MLCC on the back side is a clean way to do it.
> 
> In theory, a mod of this sort should also work on the Chaos Machine & BiPhase.  It requires more surgery on those two pedals and has not been tested (yet).



If you get the chance to look around the chaos machine lfo ticking it would be greatly appreciated !! Got 2 builds in the bin because of the ticking... Tried shielded wires and new sets of op amp from mouser and it still ticks even in bypass  !!! Thanks for all your hard work !


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## Dali

Anyone with a picture of what it looks like?

I'm trying to learn here...


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## Bobbyd67

A mlcc capacitor is a smaller size than a the box type we usually use in a build. Tayda has them. Here is a pic https://media.rs-online.com/t_large/R5381310-01.jpg


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## neil463

Robert said:


> Virtually identical.
> 
> Very grateful for the work you guys did here!
> 
> These modifications will be worked into both PCBs in the upcoming weeks.  Both boards will be marked "Rev1.3" on the back to identify that the changes have been made.
> 
> 
> 
> If your Duo-Phase ticks on the right side only (looking at the face of the enclosure) you might want to try rerouting the wire to the input jack.  It's prone to picking up LFO noise.   I've never known the other side to tick, and moving the wire has always cured the issue.    With that said, this is certainly a welcomed modification if it helps.


Can you make sure the legacy build doc also remains available to be able to reference the schematic,etc. prior to the fix?


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## Robert

neil463 said:


> So if I'm removing C19, does that mean a jumper in it's place, or leaving the spot completely empty?



Leave it empty.


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## Dali

Bobbyd67 said:


> A mlcc capacitor is a smaller size than a the box type we usually use in a build. Tayda has them. Here is a pic https://media.rs-online.com/t_large/R5381310-01.jpg



I realize my comment was open to interpretation. I was asking for a look of the modification itself, not the part.

English is not my main language... Sorry.

I can imagine how it will look but sometimes I learn a better way to do stuff by seeing exemples and builds from people here.


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## Bobbyd67

Dali said:


> I realize my comment was open to interpretation. I was asking for a look of the modification itself, not the part.
> 
> English is not my main language... Sorry.
> 
> I can imagine how it will look but sometimes I learn a better way to do stuff by seeing exemples and builds from people here.



I totally understand ! English isn't my first language as well


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## K Pedals

Dali said:


> I realize my comment was open to interpretation. I was asking for a look of the modification itself, not the part.
> 
> English is not my main language... Sorry.
> 
> I can imagine how it will look but sometimes I learn a better way to do stuff by seeing exemples and builds from people here.


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## Dali

Thanks a lot @K Pedals !

I was right that having a picture would be useful for me. My reflex would have been to use the other side of the PCB and not using some isolation as you did! You're a pro!

Thank you again !!!


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## K Pedals

Dali said:


> Thanks a lot @K Pedals !
> 
> I was right that having a picture would be useful for me. My reflex would have been to use the other side of the PCB and not using some isolation as you did! You're a pro!
> 
> Thank you again !!!


Happy to help!.¡.!


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## badpioneer

For this fix on Dark Rift, should C1 be changed to 1nf or left at 100p?


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## Chuck D. Bones

Leave C1 at 100pF.  The real fix involves C30 and is described at the beginning of this topic.


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## badpioneer

That did the trick! I had the capacitor soldered in the wrong spot before, but redid it just like in K Pedals' photo above. Tick is gone and the pedal sounds great! Thanks to everyone for their info, and Chuck D Bones for the mod!

Anyone know how hard it would be to make wet/dry know go completely wet? I suppose that might be best in its own topic.


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## Chuck D. Bones

Do you want to do it with a switch?  Or do you want the MIX control to be 100% dry at zero and 100% wet at 10?  Go ahead and start a new topic.


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## Robert

I should probably add this to the first post, but...

Any PCB shipped from today (April 2, 2020) and beyond does not require the modification/fix. 

The updated PCBs can be identified by the "Rev 1.3" marking on the back.  This applies to both the Sea Horse and Dark Rift Delay.


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## Nostradoomus

Robert said:


> I should probably add this to the first post, but...
> 
> Any PCB shipped from today (April 2, 2020) and beyond does not require the modification/fix.
> 
> The updated PCBs can be identified by the "Rev 1.3" marking on the back.  This applies to both the Sea Horse and Dark Rift Delay.



Okay that’s my last order for awhile, swear to god


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## bengarland

Is PedalPCB tracking these types of changes anywhere? I'm always curious if I've built a pedal but missed a fix like this.


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## tommasz

Robert said:


> I should probably add this to the first post, but...
> 
> Any PCB shipped from today (April 2, 2020) and beyond does not require the modification/fix.
> 
> The updated PCBs can be identified by the "Rev 1.3" marking on the back.  This applies to both the Sea Horse and Dark Rift Delay.


I have a Rev. 1.3 PCB but it still has the 47nF for C30. Do these instructions still apply? I get some ticking at certain settings.


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## Chuck D. Bones

The value of C30 is not critical.  How it's connected on the board is.  The previous rev produced ticking at all settings.  Specifically, which settings produce ticking on your pedal?


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## Robert

tommasz said:


> I have a Rev. 1.3 PCB but it still has the 47nF for C30.



That shouldn't be possible.     Can you post a pic?


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## tommasz

This is in the version of the build docs I have labeled 04.01.20. I just looked at the version on the site and it shows 10n but is also labled 04.01.20. What other changes are there?


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## Robert

What about the marking on the actual PCB?        You should generally always follow the marking on the PCB unless a value is blacked out on the board.

Aside from relocating that capacitor there were no circuit changes, but some components may have been moved around to better accommodate trace routing after the change.


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## tommasz

The PCB looks like it's marked 10n. Since I have the 1.3 board should I just replace the 47n in C30 with a 10n or should it be soldered between pins 6 and 7 on IC5?


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## Nostradoomus

I just built one of the new boards and don’t remember using a 47N, I didn’t use the build docs though.


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## tommasz

I replaced C30 with the 10n and the tick is gone.


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## Nostradoomus

An update to this issue.

I built the new Dark Rift board and had ticking once it was all boxed up (and sold, of course!?️‍♂️). It was only once the rate pot reached its almost extreme which isn’t a big deal to me as I don’t use it like that but could be an issue for the buyer. What I ended up doing was using TL022s in place of the 072s as they are lower current draw and have cured tick in quite a few LFO based builds of mine. I also grounded the footswitch PCB output with a 1M to ground and now it’s just fine and the footswitch pop is a lot more quiet as well.


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## music6000

Nostradoomus said:


> An update to this issue.
> 
> I built the new Dark Rift board and had ticking once it was all boxed up (and sold, of course!?️‍♂️). It was only once the rate pot reached its almost extreme which isn’t a big deal to me as I don’t use it like that but could be an issue for the buyer. What I ended up doing was using TL022s in place of the 072s as they are lower current draw and have cured tick in quite a few LFO based builds of mine. I also grounded the footswitch PCB output with a 1M to ground and now it’s just fine and the footswitch pop is a lot more quiet as well.


Try changing the 100k to 10k to Ground @ R15, you can remove the 1M
 to ground on the Output after as this usually fixes the pop.


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## Nostradoomus

I put it in the mail earlier today, next time!


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## music6000

Nostradoomus said:


> I put it in the mail earlier today, next time!


EQD tends to do this with their Builds & they all vary, My Stockade had 1M to ground at the same spot & Popped like hell.
If you left it for 5 minutes, it went away & with the more times you pushed the Footswitch.
I did what you did with Input & output resistors but it was still bad.
I persisted with Mr PedalPCB & he said try 100K in place of 1M.
It improved a lot but was still a pop.
Tried a 10K and it completely disappeared.
Chongmagic also had the same issue & this fixed it.
It is the Electrolytic before it that causes this.
PedalPCB has since changed the Value!


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## Chuck D. Bones

music6000 said:


> EQD tends to do this with their Builds & they all vary, My Stockade had 1M to ground at the same spot & Popped like hell.
> If you left it for 5 minutes, it went away & with the more times you pushed the Footswitch.
> I did what you did with Input & output resistors but it was still bad.
> I persisted with Mr PedalPCB & he said try 100K in place of 1M.
> It improved a lot but was still a pop.
> Tried a 10K and it completely disappeared.
> Chongmagic also had the same issue & this fixed it.
> It is the Electrolytic before it that causes this.
> PedalPCB has since changed the Value!



Anti-pop resistors only work if the capacitors to which they're connected don't leak DC.  Aluminum electrolytics are leaky and the leakage current varies with temperature.  Another reason to use MLCC, film or tantalum.


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## Nostradoomus

Yeah my output caps were C0G ceramics so it worked out fine.


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## Fingolfen

I'm getting ready to build a couple of Dark Rift Delays - is this fix still needed or has the board been updated?

Also, on the LM324 chip - I don't have any "A" models handy, but I do have an "N" - can't seem to find an "A" - thoughts?


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