Author Topic: Modded Fab Echo  (Read 41946 times)

Nalo1022

Modded Fab Echo
« on: January 31, 2006, 01:49:52 AM »
This is my first post here but ive been reding for about a month (the result of some time off due to a bandsaw accident). but to the point.

I work at a Guitar Center a we recently got the mini Danelectro Fab pedals in.I was aplynig around with the Fab Echo and liek the sound of it but was annoyed at the lack of a speed control, so i set otu to fix that. After opening the pedal up  i noticed it resembled the Rebote 2 schematic. so i replaced the fixed resistor with a 100 k linear pot and tah-dah my Fab Echo now has a speed control! I picked upthis pedal for 8 bucks with my discount and i had just done a large order from Mouser so i had the pot lying around so i now have a great sounding echo for under 10 bux! these are really great little pedals and can normally be had for about 10-15 bux. with the 100k pot as a speed control you can get anywhere from a quick doubling effect to about a 1 sec . im hoping ill have some sound clips up tomorrow.

Mark Hammer

Re: Modded Fab Echo
« Reply #1 on: January 31, 2006, 09:37:06 AM »
Now that's what I call citizenship!! :icon_biggrin:  I certainly hope your bandsaw accident didn't harm your ability to play or build or whatever else it is you do with your hands.

Thanks for tip.  I've seen Fab pedals in town for under $30 Canadian, which still is an excellent price.

Now comes the $64,000 question:  Where the hell do you PUT that extra pot?   :icon_question:  The "gabled windows" structure of the Fab cases really seem to preclude modding them in any manner off the board itself.

bioroids

Re: Modded Fab Echo
« Reply #2 on: January 31, 2006, 09:54:44 AM »
The Fab Echo uses the PT2399 too or it uses a PT2395?

Miguel
Eramos tan pobres!

Nalo1022

Re: Modded Fab Echo
« Reply #3 on: January 31, 2006, 11:22:00 AM »
it uses a PT2399, and as far as the extra pot well i simpoly superglued it to the side of the pedal until i transfer it into a new box. the bandsaw accident was the result of my cat getting in between my legs wen cutting out the neck for a guitar im building. my left pointer is pretty much healed upnow but it was rather unplesant a couple weeks ago. If anyone here is in the Nashua, New Hampshire area stop into the Guitar Center and ask for Olan (thats me) and Ill give anyone here a discount on the Fab pedals

Peter Snowberg

Re: Modded Fab Echo
« Reply #4 on: January 31, 2006, 11:43:21 AM »
Welcome to the forum! 8)

Mark is right... what a great entry!  :icon_biggrin: Very cool.

Sorry to hear about your saw accident. I hope all heals well.


Miguel, I know the Dan-Echo is PT2395 based.

Eschew paradigm obfuscation

Jamforthelamb

Re: Modded Fab Echo
« Reply #5 on: January 31, 2006, 02:25:27 PM »
Hey Nalo1022!
Thanks for the tip on this! I went and got one from this post.
Since it's all SMD could you give me a general area of where to find the resistor ?

Thanks!
JFTL

Nalo1022

Re: Modded Fab Echo
« Reply #6 on: January 31, 2006, 03:51:16 PM »
ther are two boards in the fab echothe top boardhas all the switching and power on it, the second lower board has the pots and the IC. if you follow the tracce from pin 6 thers the resistor you need to replace. lug 1 to pin 6 and lugs 2 and 3 to ground.

Re: Modded Fab Echo
« Reply #7 on: January 31, 2006, 04:37:56 PM »
Would that mod work on the danelectro slap echo DJ-3 BLT pedal?
Anyone opened one to see the delay chip?
The controls are same in both units: mix and repeats.
It would be handy delay unit if could be modded same way.
Actually I just went a musicstore this afternoon to test one
and found the sound very pleasant. The price wasn't...
They asked 75 for it! What a rip off!
And when I asked about the FAB- series pedals
they had never even heard about them... (this is very typical in Finland...
high prices and neither service nor knowledge...)
But when I did little more investigation the used ones go here for 30
That would be a solution for my problem if the mod is usable on that pedal also.
Think I would add expression pedal to control the speed.

Jamforthelamb

Re: Modded Fab Echo
« Reply #8 on: January 31, 2006, 05:21:49 PM »
Thanks Nalo1022  I got it all figured out  :D

I also looked over the schematic for the Rebote at Tonepad: http://www.tonepad.com/project.asp?id=27

I found in the schematic that you can replace a resistor to get infinite echo when the repeat knob is turned on all the way so I tried it. Works pretty cool!
It actually worked the same with a direct connection, but I've always heard that's it's good to have some kind of resistance so I put in a 1 ohm resistor.

Now I pretty much have a full fledged lofi delay pedal for 16.00.

Thanks again Nalo1022!!!!

JFTL

Nalo1022

Re: Modded Fab Echo
« Reply #9 on: January 31, 2006, 05:36:09 PM »
i uploaded a sound clip of varying degrees of the fab echo to an old myspace account so dontmind the other crappy sound clips...it says its proccessing and should be on the page in the next 24 hours

http://profile.myspace.com/index.cfm?fuseaction=user.viewprofile&friendID=7762872

Processaurus

Re: Modded Fab Echo
« Reply #10 on: January 31, 2006, 05:55:10 PM »
When you take your Fab pedals apart, be careful how the funky foil patch on the top goes back in, and that it doesn't short something out.  I got a Fab metal on tour and immediately took it apart in the van to see how it worked (nerd :icon_rolleyes:) and when I stuck it back together and powered it up later on the blue LED got bright white and then the Fab was fried.

I think all the Fab pedals have 2 circuit boards, and I'd bet the board attached to the jacks and power supply is universal in all of them (maybe its the same board from the mini Danos) and just handles the electronic switching and power supply filtering, and the board attached to the pots is the actual effect.

I'm curious about whats in the chorus too, maybe someone could lash together a DC-2 workalike with two of them.  I was seeing all those pedals for like $15 at guitar centers we stopped by.  Its creepy how cheap they are.   Made by nimble fingered elves in China...

Nalo1022

Re: Modded Fab Echo
« Reply #11 on: January 31, 2006, 11:42:24 PM »
from what ive seen of the other pedals the switching board does appear to be universal. i plan at some point to transfer the pdal into a better all metal housing. i could try to get some pics of the boards online if someone was interested in them.

Processaurus

Re: Modded Fab Echo
« Reply #12 on: February 01, 2006, 05:01:52 AM »
Now comes the $64,000 question:  Where the hell do you PUT that extra pot?   :icon_question:  The "gabled windows" structure of the Fab cases really seem to preclude modding them in any manner off the board itself.

The middle gable on the Fab echo is left conspiciously empty, you might be able to drill it out and squeeze a panel mount 9mm pot in there like Boss uses (the pots Danelectro use are the little Alpha PCB mount ones just like on the Zvex Seek Wahs)

Nalo1022

Re: Modded Fab Echo
« Reply #13 on: February 03, 2006, 12:42:05 AM »
the soundclip is now availible just to get an idea of the mod sounds. the quality isnt that great but it was recorded through the mic on my webcam cuz it was all i had access to at the time. The guitar was my first guitar ever(double-cut Slammer by Hamer with a dimarzio supoer distortion in it) into the fab echo then into my Bassman head through a old peavey 412, but you get the idea.

Dave_B

Re: Modded Fab Echo (with pics of stock board)
« Reply #14 on: June 08, 2006, 06:13:09 PM »
Processaurus (or anyone who knows), is there a trick to removing the effect board?  I unscrewed everything, but I'm a little reluctant to start prying.  Here's a pic of the echo board.  I tried to compress it for the dial-up folks.



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Processaurus

Re: Modded Fab Echo
« Reply #15 on: June 08, 2006, 07:25:49 PM »
Good pictures, to get it out, its a little bit of a pry, you pull the knobs off (I had to use pliers, if I remember), and then you have to simultaneously pull up and back (away from the pot shaft "gabled windows"), so the pot shafts don't lever the pot off the board..  The LED seems to have no choice but get bent on its way out.

I think a 16mm pot may be able fit around the "B" in FAB on the top of the pedal, if one measured carefully, because there is an empty spot on top of the PCB there.  You'd have to plan ahead on how you'd get the board back in, though (long wires to the new pot, probably).  Alternately, if it helps, the film caps in front of the middle window (C6 and C2) could get stuck on the SMD side of the PCB, and not hit anything.

After looking at the trouble it would be to do all this, I'd say someone interested in the economics of the situation should spend the extra $10 bucks on the PB&J delay... with mine, I'm probably gonna rob the tiny delay PCB (2 1/4" x 1 3/8") and stick it in another effect, (maybe the EH Polychorus, or a theremin...), maybe keep the FAB enclosure and switching board, and put a small Tim Escobedo-esque circuit in there, or a no knobber...

markm

Re: Modded Fab Echo
« Reply #16 on: June 08, 2006, 07:38:33 PM »
I find surface mount intimidating........
Yet, it's so small ;)
I don't know how you guys could work with it?!

Dave_B

Re: Modded Fab Echo
« Reply #17 on: June 28, 2006, 10:14:25 PM »
Good pictures
Thanks!
Quote
After looking at the trouble it would be to do all this, I'd say someone interested in the economics of the situation should spend the extra $10 bucks on the PB&J delay...
Where have you seen them for that price?  I've only seen them in the $50-60US range.
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Dave_B

Re: Modded Fab Echo
« Reply #18 on: June 28, 2006, 10:20:09 PM »
I find surface mount intimidating........
Yet, it's so small ;)
I don't know how you guys could work with it?!
I'm fortunate to have a wife who used to do assembly work.  She's not at all intimidated by SMD's.  I'm pretty sure I'd mess it up. 
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2deaconblues

Re: Modded Fab Echo
« Reply #19 on: April 06, 2007, 12:23:34 PM »
I'd like to give this mod a try, and after reading this thread and the great project at www.beavisaudio.com, I opened up my FAB Chorus and I have one question. How the heck do you get that tiny resistor out of there? I've desoldered stuff before, but never anything that tiny.