Earthquaker Devices Palisades  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.

Re: Earthquaker Devices Palisades

Postby Manfred » 29 Oct 2017, 18:47

I have another question: does the signal-phase stay the same when the mpsa18 is used inversely?
If so, then this could be the answer.


The signal-phase stay the same.

For this message the author Manfred has received thanks:
Intripped (29 Oct 2017, 23:28)
Manfred
Cap Cooler
 
Posts: 658
Joined: 05 Apr 2009, 00:42
Has thanked: 943 times
Have thanks: 494 times

Re: Earthquaker Devices Palisades

Postby modman » 01 Nov 2017, 14:23

You do not have the required permissions to view the files attached to this post.
"The whole point of diy is diy. It's not dsoiyathodtr - do some of it yourself and then have others do the rest" (paulc)

For this message the author modman has received thanks: 2
bmxguitarsbmx (01 Nov 2017, 18:48), dv8r601 (08 Nov 2017, 00:50)
User avatar
modman
a d m i n
 
Posts: 4298
Joined: 19 Jun 2007, 17:57
Has thanked: 3107 times
Have thanks: 546 times

Re: Earthquaker Devices Palisades

Postby kmmoe » 07 Nov 2017, 11:54

Albru80's layout have now been confirmed over at tagboardeffects. There is still the mystery diode, but as both the pictures shown in this post by modman, and the comments over at tagboardeffects show, diffused red 3mm have been used by EQD, and sounds good.
kmmoe
 
Posts: 8
Joined: 25 Jan 2016, 18:09
Has thanked: 4 times
Have thanks: 13 times

Re: Earthquaker Devices Palisades

Postby storyboardist » 07 Nov 2017, 15:35

Here's a perf/pcb layout for this. Pots are board mounted, switches are off board. Best fit is going to be in a 1790NS like the original.

Image

For this message the author storyboardist has received thanks: 7
287m (07 Nov 2017, 21:32), dv8r601 (08 Nov 2017, 00:50), hippo (07 Nov 2017, 22:52), IzotopCustom (18 Nov 2017, 23:30), kmmoe (07 Nov 2017, 17:42), Manfred (07 Nov 2017, 17:10), sego91 (09 Nov 2017, 17:06)
User avatar
storyboardist
Breadboard Brother
 
Posts: 83
Joined: 28 Dec 2013, 01:08
Location: Georgia, USA
Has thanked: 62 times
Have thanks: 166 times

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
POTL
Resistor Ronker
 
Posts: 275
Joined: 26 Sep 2016, 04:11
Has thanked: 64 times
Have thanks: 54 times

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
User avatar
storyboardist
Breadboard Brother
 
Posts: 83
Joined: 28 Dec 2013, 01:08
Location: Georgia, USA
Has thanked: 62 times
Have thanks: 166 times

Re: Earthquaker Devices Palisades

Postby kmmoe » 07 Nov 2017, 23:10

@ Storyboardist. It is an MPSA13 in the booster, not an MPSA18.
kmmoe
 
Posts: 8
Joined: 25 Jan 2016, 18:09
Has thanked: 4 times
Have thanks: 13 times

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
User avatar
storyboardist
Breadboard Brother
 
Posts: 83
Joined: 28 Dec 2013, 01:08
Location: Georgia, USA
Has thanked: 62 times
Have thanks: 166 times

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:
User avatar
jalmonsalmon
Solder Soldier
 
Posts: 194
Joined: 14 Sep 2012, 23:49
Has thanked: 66 times
Have thanks: 23 times

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.

For this message the author kmmoe has received thanks:
jalmonsalmon (13 Nov 2017, 04:58)
kmmoe
 
Posts: 8
Joined: 25 Jan 2016, 18:09
Has thanked: 4 times
Have thanks: 13 times

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:
Manfred
Cap Cooler
 
Posts: 658
Joined: 05 Apr 2009, 00:42
Has thanked: 943 times
Have thanks: 494 times

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:
Nick123
 
Posts: 28
Joined: 02 Jul 2007, 10:13
Has thanked: 7 times
Have thanks: 9 times

Re: Earthquaker Devices Palisades

Postby Visualdistortion » 27 Nov 2017, 22:02

Some people reported issues with Tagboard build, any news on a "more" verified schematic?
I wanna make it
I wanna make it wit chu
(again and again and again)

French... sorry ;)
User avatar
Visualdistortion
Breadboard Brother
 
Posts: 85
Joined: 17 Aug 2008, 23:20
Has thanked: 7 times
Have thanks: 17 times

Re: Earthquaker Devices Palisades

Postby dahliacorpse1 » 04 Jan 2018, 22:00

I built this from tagboard. Everything works but the boost. The boost volume goes to just under unity gain. Everything else seems to work well though
dahliacorpse1
 
Posts: 1
Joined: 04 Jan 2018, 21:57
Has thanked: 0 time
Have thanks: 0 time

Re: Earthquaker Devices Palisades

Postby Visualdistortion » 01 Jul 2018, 19:13

Nobody solved the booster issues of the Tagboard vero?
I will love to add it to my rig
I wanna make it
I wanna make it wit chu
(again and again and again)

French... sorry ;)
User avatar
Visualdistortion
Breadboard Brother
 
Posts: 85
Joined: 17 Aug 2008, 23:20
Has thanked: 7 times
Have thanks: 17 times

Previous

Return to Boutique Stompboxes dissected...

Who is online

Users browsing this forum: globus46, pilekana and 6 guests