Earthquaker Devices Palisades  [traced]

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Re: Earthquaker Devices Palisades

Postby POTL » 07 Nov 2017, 21:55

There are a couple of ideas for improving the scheme
1) The output buffer and booster must be interchanged, then in boost mode the output impedance will not change - so it is more logical
2) The input buffer is not to be disabled, but in the 3pdt button there are 2 pins connected between the sobo (bottom row, right and bottom pins, connect to the buffer, using the DPDT toggle switch)
This will enable the selection of a bypass, and in the operation mode of the overdrive we will always have a buffer at the input.
3) Volume potentiometer should be changed to A10K
4) Boost potentiometer should be replaced by A100K
this will give smoother adjustments
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Re: Earthquaker Devices Palisades

Postby storyboardist » 07 Nov 2017, 22:16

Got a comment on my Instagram from a guy who works for EQD who said "You have some discrete misses." So unless he's trolling (which I kinda doubt), we're close but not quiet there yet.

https://www.instagram.com/p/BbMo0FLn_7x ... ctslayouts
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Re: Earthquaker Devices Palisades

Postby kmmoe » 07 Nov 2017, 23:10

@ Storyboardist. It is an MPSA13 in the booster, not an MPSA18.
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Re: Earthquaker Devices Palisades

Postby storyboardist » 08 Nov 2017, 15:37

kmmoe wrote:@ Storyboardist. It is an MPSA13 in the booster, not an MPSA18.


Fixed
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Re: Earthquaker Devices Palisades

Postby jalmonsalmon » 10 Nov 2017, 05:24

storyboardist wrote:Got a comment on my Instagram from a guy who works for EQD who said "You have some discrete misses." So unless he's trolling (which I kinda doubt), we're close but not quiet there yet.

https://www.instagram.com/p/BbMo0FLn_7x ... ctslayouts

I think the schematic posted is more or less in the right ball park so maybe it has something to do with the boost :scratch:
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Re: Earthquaker Devices Palisades

Postby kmmoe » 12 Nov 2017, 23:07

I have gone through the whole schematic one more time, and I really can't find anything that does not add up. I have measured all the connections I can't see clearly, measured all the caps and resistors in the original pedal, and it all checks out. Just beware that the original pedal uses a B100K volume pot, not a A100K, if you want it correct.

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Re: Earthquaker Devices Palisades

Postby Manfred » 14 Nov 2017, 04:07

What makes to me, nevertheless, taken aback the fact that the input buffer headroom is noticeably reduced when the transistor works in the inverse operation mode, the buffer output signal starts clipping at a input voltage of 250 Millivolts.
In the normal operation mode the output signal starts clipping at a input voltage of 2.6 Volts.
:scratch:
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Re: Earthquaker Devices Palisades

Postby Nick123 » 14 Nov 2017, 12:38

So it could be the twisted designers logic - without buffer is actually the "buffered" sound ? :scratch:
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