Author Topic: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)  (Read 5172 times)

RonaldB

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Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« on: June 06, 2012, 10:39:35 PM »
Hi,
After building the dirtbag with the V3205 chips I wasn't really happy with the sound.
So I purchased the MN3005 fakes from smallbear (2 sets). I made a little prefboard layout and changed the circuit to the MN3005 standard. Now the echo is beautifull.
What I did changed was for R11 and R12 39K instead of 68K. Somhow I liked it better with those values.

And after reading this post last night:
http://www.madbeanpedals.com/forum/index.php?topic=5090.0
I added a 100R resistor after C32. I will be trying a 1K potentiometer in the future.


Looks haven't changed, sound Oh yes. THANKS MADBEAN.

njkke

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #1 on: June 07, 2012, 01:59:53 AM »
Can you tell me more about your mods? I've built a dirtbag with MN3205 that works one day at week! Probably the MN3205 from Hong Kong are instable in some way I don't know... I'd like to switch it to a MN3008 version, simplier to find in europe...

RonaldB

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #2 on: June 07, 2012, 04:47:04 AM »
I used the schematic Small bear added in his shop:
http://www.smallbearelec.com/servlet/Detail?no=247

And followed Madbean documentation to redo all the changes made for the V3205 version.

I'm also in europe (the Netherlands) to be exact. But ordering from Small Bear was easy and cheap.
Got them send in a week for 33 euro's.

best of luck
RonaldB

gtr2

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #3 on: June 07, 2012, 05:07:12 AM »
Nice build.

Gut pics are required  ;D

Josh
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the3secondrule

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #4 on: June 07, 2012, 06:02:22 AM »
What I did changed was for R11 and R12 39K instead of 68K. Somhow I liked it better with those values.

What effect did/would this have?

cheers,

J
"I have many leatherbound books, and my apartment smells of rich mahogany"

RonaldB

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #5 on: June 07, 2012, 06:23:24 AM »
They will follow  ;)
But because of the prefboard there is lots of spagetti in there (16 wires) ;D

RonaldB

madbean

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #6 on: June 07, 2012, 06:55:10 AM »
What I did changed was for R11 and R12 39K instead of 68K. Somhow I liked it better with those values.

What effect did/would this have?

cheers,

J

It reduces the output of the compressor portion of the compander. IIRC, 39k is the value used on the Memory Boy which uses 4x BL3208a.
I own madbeanpedals (duh). I am part owner of Function F(X).

LaceSensor

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #7 on: June 07, 2012, 08:05:13 AM »
They will follow  ;)
But because of the prefboard there is lots of spagetti in there (16 wires) ;D

RonaldB

please consider to post your doubledelay board layouts ? thanks

RonaldB

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #8 on: June 07, 2012, 11:41:38 AM »
Lacesensor:
I will draw one up tommorow. I did this one out of the top of my head.

Madbean:
I Think the 68K would work also but i'm happy with the 39K for now.
Will the dirtbag delay PCB's be stocked again soon?

RonaldB

sgmezei

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #9 on: June 07, 2012, 03:03:47 PM »
I would consider putting in a bypass switch. That way it isn't always on...... ;D

RonaldB

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #10 on: June 07, 2012, 10:40:09 PM »
i have all my effects routed through a bypass looper, no need for a switch in pedals then. ;D

RonaldB

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #11 on: June 08, 2012, 02:45:18 AM »
Here is the pref layout I would use the next time I will make these double delay boards.
Mine are a mess now but they work ;D


LaceSensor

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #12 on: June 08, 2012, 05:41:01 AM »
thanks

pickdropper

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #13 on: June 08, 2012, 06:18:35 AM »
I think a layout that used PCB mount pin headers could clean up the wiring quite a lot.

After I finish up a few other things, I may make a go at it.

[EDIT] - Nevermind, I see that Smallbear has the PCB layout for this already on their site.
« Last Edit: June 08, 2012, 06:31:29 AM by pickdropper »
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LaceSensor

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Re: Dirtbag with 4xMN3008 (MN3005 fakes from smallbear)
« Reply #14 on: June 08, 2012, 11:26:26 AM »
HI

This also works (at least in an aqua puss build)

http://www.sabrotone.com/?p=698