Emma - DB-1 DB-2 DiscumBOBulator

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
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Mbas974
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Post by Mbas974 »

Wow, looks not really hard to build... :-)

but, what are the boxes called "1" (INV_XX).
I image it's a sort of logic port.

Any idea what could be the chip involved ?

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roseblood11
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Post by roseblood11 »

I just realized that there is a second version of this pedal, and I hope we'll get this traced.
The first version was based on the MXR envelope filter, with some mods, maybe with additional buffer(s). Clones of the MXR that had the mods described on tonepad sounded more or less identical.

http://www.emmaelectronic.com/discumbobulator/

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modman
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Post by modman »

I merged all Emma - DiscumBOBulator post into one thread because all the schematics have dissapeared as well as all gutshots.
Please use the attachment function to preserve shit for posterity! thanks
Please, support freestompboxes.org on Patreon for just 1 pcb per year! Or donate directly through PayPal

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POTL
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Post by POTL »

Image

not verified![/color]

Image

Image
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Emma_DiscumBOBulator.jpg

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rs
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Post by rs »

Here are some guts i've found a while ago.
I'm still trying to figure this one out.

Cheers.
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chicago_mike
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Post by chicago_mike »

For the input and output caps in the Emma, I just used .022 Panasonics. sounds fine!
Skyline FX 2013

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rs
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Post by rs »

Hi Mike, wich schematic did you use? Im getting strange noises. Have to check it latter. Thanks.

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roseblood11
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roseblood11
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Post by roseblood11 »

Just ordered version 2. I will post photos and schematic next week

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roseblood11
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Post by roseblood11 »

Version 2 is all smd.
As my wife is in hospital, I won't have time to do the tracing myself but I will take some macro shots.
The pedal doesn't sound better than the old version, but it might have more headroom, as it can be used with bass or power humbuckers without any distortion.
The clean boost is a useful addition, but there should be an option to change its position in the signal path: Often, it would be more useful, if the boost was directly behind the output of the wah circuit, so that the wah's bypass switch would switch both effects at the same time.
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roseblood11
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Post by roseblood11 »

Hi Res pictures...
https://www.dropbox.com/s/7nuueym110d86v2/emma.zip?dl=0

Unfortunately, I won't have time to draw the schematic. Maybe someone else will do that?

What more is needed?

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roseblood11
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Post by roseblood11 »

This is a bigger version of Bernard D'Uurs scheamtic of the old version DB-1.

Maybe it's helpful...


Any ideas on how to get the values of those smd capacitors? They aren't labeled...
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Emma - DiscumBOBulator.JPG

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roseblood11
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Post by roseblood11 »

I had to return the pedal today.
But the pictures should be all that is needed to draw a schematic.

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