Moog - MuRF

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Moog - MuRF

Postby borislavgajic » 27 Jun 2008, 15:40

can enyone say something about this simple circuit?
is it like the Fuzz Face,or it is different?
schematic?



p.s.

.... Alex Frias is not going to understand this kind of humor..... :applause:
sorry Alex...I know that there is 8 filter array......bla bla bla......but some guts? or schem??? :thumbsup
Last edited by borislavgajic on 27 Jun 2008, 16:08, edited 1 time in total.
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Re: Moog-MuRF

Postby Alex Frias » 27 Jun 2008, 15:48

Gosh...
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Re: Moog-MuRF

Postby borislavgajic » 27 Jun 2008, 20:42

I found this......http://img.photobucket.com/albums/v21/m ... dsmall.jpg

but how would you make switching those filters? any ideas?

and patent from moog...http://www.freepatentsonline.com/4117413.html

sequencer like in seekwah?.........help me please :|
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Re: Moog-MuRF

Postby Supafuzz » 02 Jul 2008, 00:33

borislavgajic wrote:I found this......http://img.photobucket.com/albums/v21/m ... dsmall.jpg

but how would you make switching those filters? any ideas?

and patent from moog...http://www.freepatentsonline.com/4117413.html

sequencer like in seekwah?.........help me please :|


No. Just a 1/4 octave high mid-treble equalizer. Its output is mixed with original signal so it basically produces a kind of comb filter response.
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Re: Moog - MuRF

Postby borislavgajic » 02 Jul 2008, 15:18

thank You ...... but do you have some idea??? how it is done :?: :idea:

have a nice day
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Re: Moog - MuRF

Postby Alex Frias » 02 Jul 2008, 19:44

It's more complicated than FF's, pal!
It will get one or two transistors more!!!
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Re: Moog - MuRF

Postby borislavgajic » 02 Jul 2008, 21:21

:thumbsup I know.......but I am ready if you are ( just need some good pictures)......and help from my friends.... :thumbsup
we all could do anything........that is why this beaytiful place is called FREESTOMPBOXES

AND everybody DON'T FORGET THAT!!!!!!!!! :hug:


P.S
addicted to smiles
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Re: Moog - MuRF

Postby celadine » 02 Jul 2008, 22:30

Ah, the filter schem you have looks like the "combats aural fatigue" filter Moog patented and which was used in the Norlin Lab series guitar amps.

For the most part the murf isn't a mystery. 8 graphic eq filters; each filter has its own VCA (voltage controlled amplifier). A micro-controller (PIC, atmel AVR, etc.) handles the sequencing and envelope generation. The unknown is how it does the frequency modulation of all 8 filters at once ('chorus'). There are many obvious ways to do this, but they involve additional circuitry for each filter. IMO the frequency modulation is some side effect of the filter construction which makes the modulation easily implemented.

If you want to clone this, practice your micro-controller programming... :block:
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Re: Moog - MuRF

Postby pbone » 24 Nov 2008, 21:06

http://i277.photobucket.com/albums/kk64 ... hoto11.jpg

Some guts. Looks like a dual-tiered PCB. I'm returning it today so I wasn't too hot on taking it all apart, but there's the first part.
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Re: Moog - MuRF

Postby celadine » 25 Nov 2008, 02:41

:shock: holeeeeee...

O.K., maybe the sequencer is analog! Did you happen to see what kind of chips are in there?
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Re: Moog - MuRF

Postby borislavgajic » 29 Nov 2008, 11:00

pbone wrote:http://i277.photobucket.com/albums/kk64/TheAirport/Photo11.jpg

Some guts. Looks like a dual-tiered PCB. I'm returning it today so I wasn't too hot on taking it all apart, but there's the first part.


thank you.................but it looks very easy to build and even easier to trace :hmmm:

.........like superhardon :( :? :blackeye :blackeye :blackeye
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