KORG - FK-2 Mr. Multi Phase - Wah - Double Wah  [schematic]

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Re: KORG - FK-2 Mr. Multi Phase - Wah - Double Wah

Postby bernhard42 » 16 Apr 2018, 23:04

Hi Jimi,

thanks!

I checked the boards from deadendfx.com, thanks for the hint. I guess the thing with the highpass buffer is too far from the original design, so i'll build mine from scratch on vero, i guess. And then the output buffer... i can't imagine myself successfully fumbling another opamp chip on a ready pcb...

Maybe you wanna wait for mine to work (or not ;)) before you start building yours - it's only simulation so far :D
Or do you build the deadendfx project as is?

I saw your video on the pedal.. really looking forward to having my own Mr. Multi!

Cheers

Bernhard
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Re: KORG - FK-2 Mr. Multi Phase - Wah - Double Wah

Postby PMowdes » 18 Apr 2018, 11:57

bernhard42 wrote:Hi Jimi,

thanks!

I checked the boards from deadendfx.com, thanks for the hint. I guess the thing with the highpass buffer is too far from the original design, so i'll build mine from scratch on vero, i guess. And then the output buffer... i can't imagine myself successfully fumbling another opamp chip on a ready pcb...

Maybe you wanna wait for mine to work (or not ;)) before you start building yours - it's only simulation so far :D
Or do you build the deadendfx project as is?

I saw your video on the pedal.. really looking forward to having my own Mr. Multi!

Cheers

Bernhard


I'm really interested to see how this compares to our version. The phaser and wah aren't great on their own, but in combo it really is a fun pedal. Let Dino or I know how it turns out and perhaps we can generate a pcb design if you are interested.

Phil
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Re: KORG - FK-2 Mr. Multi Phase - Wah - Double Wah

Postby bernhard42 » 18 Apr 2018, 15:13

Hey Phil,

thanks for your feedback!
I've started populating the board - still waiting for some parts though.
I'll keep you updated! When the pedal works I'll record something, and then we can see if it's worth its own PCB.

Cheers,

Bernhard
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Re: KORG - FK-2 Mr. Multi Phase - Wah - Double Wah

Postby pinkjimiphoton » 18 Apr 2018, 16:20

makin popcorn lol :popcorn:

i have a working original if any thing needs verification or anything. :horsey:

i have two versions of phil and dino's board, i look forward to getting it built soon. slow. i take forever.

but very curious to see how it works out!! :thumbsup
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Re: KORG - FK-2 Mr. Multi Phase - Wah - Double Wah

Postby digi2t » 19 Apr 2018, 15:01

Phaser quality really depends on jfet selection. The tighter you can group the jfet's, the better the phaser will sound.

My first time around, I just threw a set of random jfet's in there, and it sounded like oatmeal.
No matter how many times I cut it, it`s STILL too short!

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Re: KORG - FK-2 Mr. Multi Phase - Wah - Double Wah

Postby bernhard42 » Yesterday, 14:40

digi2t wrote:Phaser quality really depends on jfet selection.


Definitely. I'm trying homemade photocouplers with a suitable LFO this time though, as my parts bucket is full of LDRs from my last Non-RoHS-Parts-Go-Extinct-Panic-Shopping.

Matching applies in the same way, though i guess the parameter variations of LDRs are not as extreme as with JFETs. And the matching of LEDs can be done quite easily by running them in series - all with the exact same current.

Let's see how it works out... Still waiting for the mailman to bring the 4558...

Have you tried that phaser with some reverb back then, to get that true Hall & Oats sound? ;)

Cheers

Bernhard
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Re: KORG - FK-2 Mr. Multi Phase - Wah - Double Wah

Postby pinkjimiphoton » Yesterday, 17:56

reverb is a must always bernie ;)

sounds killer with reverb, you'll know ya got it when in double mode it starts going yoy yoy. its the formanty aspect that made me dig this circuit so much.

i gotta rully wow jfet matcher for doing this project, and a sack of 150 jfets to hopefully find a decent set.

still lurking, still makin popcorn :popcorn:
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