Mwfx judder

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LaceSensor
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Post by LaceSensor »

Anyon got any info on this?

It's a pt2399 based sample and hold type effect.

http://www.mwfx.co.uk/judder

Thanks in advance

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~arph
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Post by ~arph »

No info, but I can think of how it can be done.

In normal operation the PT2399 gets the input signal. and the output is taken from the direct signal.

Then when you press a footswitch you:

Connect the input of the PT2399 to the output of the PT2399 and you take the pedal output from the PT2399 output. (buffered)

That should do the trick.
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LaceSensor
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Post by LaceSensor »

I am a complete noob in terms of "designing" a pedal.

Any help with how to get a workalike off the ground?
Building blocks of a regular pt2399 delay like the rebote but simplified down?

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Post by ~arph »

Yes, minus the heavy filtering. I'll see if I can draw something up when I get some time.
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Post by LaceSensor »

~arph wrote:Yes, minus the heavy filtering. I'll see if I can draw something up when I get some time.
that would rule

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~arph
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Post by ~arph »

Ok, quick sketch.

The switches are a 3PDT momentary footswitch.

In the unpressed state. the guitar signal is routed to the output of the pedal and the input of the PT2399

When pressed, the output of the pedal is taken from the buffered PT2399 output.
The input of the PT2399 is taken from the direct output of the PT2399.

The filter section is gone, this is an allpass configuration. The delay time can be adjusted like normal.
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Screen Shot 2013-06-13 at 11.42.44 .png
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LaceSensor
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Post by LaceSensor »

Hi

My attempt at a vero for this. Not done one in ages, so shit loads of jumpers.
but, I think all connections are correct. Footswitch might be wrong...

Someone take a quick look over?

Numbering as per ~arph shcematic
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JUDDER VERO 3.jpg

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Post by LaceSensor »

LaceSensor wrote:Hi

My attempt at a vero for this. Not done one in ages, so shit loads of jumpers.
but, I think all connections are correct. Footswitch might be wrong...

Someone take a quick look over?

Numbering as per ~arph shcematic
Hi

This doesnt work, so can someone give a 2nd set of eyes?

I get signal (and delayed signal) on 10 and 12 of the PT2399, but nothing gets outta pin 14...

help!?

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Post by LaceSensor »

Went and dragged up my rushed photos on the original.
As you can see its a hellish rats nest. Includes a dual op amp, couple of transistors
The control is a dual pot
Its just using a spst momentary switch...

thanks

Image

Image

Image

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~arph
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Post by ~arph »

Wow this really took off while the forum was inaccesable for me. As I stated it was a quick sketch on how I think it can be done. Unverified an not even tried on the breadboard. The delay section was copied from a different project, so component values me be off too. If it works from that I'd be happily surprised.

Btw, I am happily surprised the original works as well judging from those photos :shock:
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LaceSensor
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Post by LaceSensor »

ah. ok.

I might just try something around a PT delay then which I know works and then remove the filtering later perhaps.
Something is off with the build regardless, but I can get delayed signal which is start (audio probing).

Want to know how the real ones work but fuck funding that guy who puts out garbage products like that.
Impossible to reverse, too, as its such a rats nest.

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Post by Dr Tony Balls »

You know, this kind of thing is very similar to the slam switch mod which is possible on almost all delay pedals. just add a momentary switch that shorts the pins on the feedback pot so that it is effectively turned all the way up and oscillation occurs. I dont think it necessarily needs to be a standalone unit....could just be added to any delay.

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Post by LaceSensor »

Dr Tony Balls wrote:You know, this kind of thing is very similar to the slam switch mod which is possible on almost all delay pedals. just add a momentary switch that shorts the pins on the feedback pot so that it is effectively turned all the way up and oscillation occurs. I dont think it necessarily needs to be a standalone unit....could just be added to any delay.
Not the same thing though, it doesnt go super loud like those slam things, and its like the delay is always on (the original judder has a 3pdt toggle to true bypass the effect, but you are always leaving it ON) so that the "judder" is instantly accessible. Its not the same as having to turn a delay on then "slam" it...

but thanks for the input

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Post by Beedoola »

LaceSensor wrote:Went and dragged up my rushed photos on the original.
As you can see its a hellish rats nest. Includes a dual op amp, couple of transistors
The control is a dual pot
Its just using a spst momentary switch...

thanks

[ Image ]

[ Image ]

[ Image ]
did you try breadboarding the circuit before the vero/have you attempted that since the build? Maybe your build isn't the problem but the schematic is not correct: as arph said it was a sketch/preliminary idea.

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LaceSensor
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Post by LaceSensor »

I don't own a breadboard ... :oops: :shock:

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Post by Beedoola »

LaceSensor wrote:I don't own a breadboard ... :oops: :shock:
someone get this man a breadboard, stat!!

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zuzuzaza
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Post by zuzuzaza »

LaceSensor wrote:Went and dragged up my rushed photos on the original.
As you can see its a hellish rats nest. Includes a dual op amp, couple of transistors
The control is a dual pot
Its just using a spst momentary switch...

thanks

[ Image ]

[ Image ]

[ Image ]
I want to see some more guts...

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Post by DWBH »


Judder Clone ^^

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Post by KoenT »

Is there any news on this one? I get some stutter on breadboard by conntecting pin 14 to pin 16 but it is not very useful at the moment.

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Post by lborl »

Sorry for the necropost but did anyone happen to save the gutshots LaceSensor posted in 2013, or know of any others?

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