Friedman BE-OD

Started by rroza, February 16, 2017, 10:28:46 AM

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rroza

I picked up a Friedman BE-OD last year.  It's a FET-based distortion pedal similar to the JCM800, Boogie and others out there.

It has some very promising attributes, but still not correct and not a lot of difference in gain as breaks up immediately and likewise very bright.

I'd like to reverse engineer it and then redesign it better and what it should be and include things missing like a MID control.  If anyone is interested, please feel free to stay tuned!  :)

bancika

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nocentelli

Quote from: rroza on February 16, 2017, 10:28:46 AM
I picked up a Friedman BE-OD last year.  It's a FET-based distortion pedal...

FET-based, or JFET input opamp-based?
Quote from: kayceesqueeze on the back and never open it up again

Groovenut

Quote from: nocentelli on February 16, 2017, 03:13:18 PM
Quote from: rroza on February 16, 2017, 10:28:46 AM
I picked up a Friedman BE-OD last year.  It's a FET-based distortion pedal...

FET-based, or JFET input opamp-based?
It's opamp based. TL072's I believe. Nary a discrete JFet to be had. Diode clipping most likely.

my 2 cents....
You've got to love obsolete technology.....

robthequiet

#4
According to the diagram I found which I cannot vouch for as authentic, there is a TL072 (IC2A) stage with 2 BAT54 diode pairs arranged in opposite directions. Maybe a switch to [..edit...] insert a resistor in series, might tame some of the early onset distortion. The first clipping stage has LEDs in the feedback loop, so not much to change there except maybe step down the gain pot. Imgur has me in moderation mode so maybe I can post what I have, although not sure if Friedman is on approved list to review here.

It looks like a soft-clip OD with a lot of stages and clipping diodes. I think the "Tight" knob may be scrutinized as a path for modification.

Ah, Imgur lets me post privately. https://imgur.com/a/gYTJg-- not sure if this is totally accurate or where it came from, but I'll hang it out there for now.

J0K3RX

#5
Half way traced it over in "the other forum" but the guy who supplied the pics dropped off the map and coudn't verify anything or get any better shots..  :P

https://www.dropbox.com/sh/adl2ow5whhueowl/AAB6MUhjESUufrqMOIXP-J2ga?dl=0

The pcb is black which makes it difficult to trace from just a picture and with limited pics and no way to verify stuff leaves a lot of guesswork... If I had one in hand I would make quick work of it.. but I don't so I am waiting for some more pics and maybe somebody to verify things on the other end..

robthequiet - That schematic is from the other forum and has a lot of guesswork on it.. may work and sound great but, it's not accurate. From what I can tell in the photos and the marking on the SOT23 they appear to be BAV99 fast switching diodes..
http://assets.nexperia.com/documents/data-sheet/BAV99_SER.pdf
Doesn't matter what you did to get it... If it sounds good, then it is good!

robthequiet

@JokerX Yeah, it came with caveats.

otoh, our OP has one - ::)- @rroza, any chance you might be able to post some photos of the circuit board? You would have the best panel of experts available to help you figure it out.


rumbletone

Have you thought about starting with the wampler plexi-drive and adding a gain stage and full eq? To my ears those circuits are closer to the original amps' feel/breakup/touch sensitivity than any diode-clipping-based drives I've played.


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J0K3RX

Quote from: rumbletone on February 17, 2017, 12:34:09 AM
Have you thought about starting with the wampler plexi-drive and adding a gain stage and full eq? To my ears those circuits are closer to the original amps' feel/breakup/touch sensitivity than any diode-clipping-based drives I've played.


Sent from my iPhone using Tapatalk

No, not really..

Funny you say that about the diode clipping because in this case the "original amp" that is being emulated is the Friedman Brown Eye 100 which ironically has diode and mosfet clipping...   :icon_neutral:

http://music-electronics-forum.com/attachments/39789d1467770843-be100-v2-rev1.5.png

If I were going to go the JFET emulation route I would use one of the many Jose' modded type Marshall schematics that can be found widely all over the internet and try to get a scaled JFET version worked out..  Dave Friedman is one of the leaders in the "Jose Arredondo EVH modded Marshall" type amp clones. But he is just one of many in this niche market.. There is also Mark Cameron, Mike Fortin among the leaders and then a whole sea of wanna bee's vomiting forth their versions of the same old sh!t..  :icon_rolleyes:

http://schems.com/bmampscom/fortin/Fortin%20Cali%20Mod.png

From listening to the youtube videos it doesn't sound like the BE-OD pedal is missing any feel, breakup or touch sensitivity from what my ears can tell.. If anything it may be the closest I have ever heard of any pedal to actually get "The EVH modded Marshall /Brown sound!"... I realize that statement is debatable but, I ain't in the mood for a debate, so... save it for yer mama..  :icon_twisted:

I think Pete Thorn really puts it through the paces in this video and sounds insanely good! :o
Doesn't matter what you did to get it... If it sounds good, then it is good!

luciano

I builded one ... the sound is great, really like be od , I changeed bav99 with 4- 4148 739mv , I used red leds for other clipping . Only problem is the presence control , in the second opam position not work , between the first gain pot work just little well.
Quote from: J0K3RX on February 16, 2017, 07:35:38 PM
Half way traced it over in "the other forum" but the guy who supplied the pics dropped off the map and coudn't verify anything or get any better shots..  :P

https://www.dropbox.com/sh/adl2ow5whhueowl/AAB6MUhjESUufrqMOIXP-J2ga?dl=0

The pcb is black which makes it difficult to trace from just a picture and with limited pics and no way to verify stuff leaves a lot of guesswork... If I had one in hand I would make quick work of it.. but I don't so I am waiting for some more pics and maybe somebody to verify things on the other end..

robthequiet - That schematic is from the other forum and has a lot of guesswork on it.. may work and sound great but, it's not accurate. From what I can tell in the photos and the marking on the SOT23 they appear to be BAV99 fast switching diodes..
http://assets.nexperia.com/documents/data-sheet/BAV99_SER.pdf

luciano

in your photo the presence pot is connect with C13 for pin 3, pin 2 and pin1 are connect with ?
Quote from: J0K3RX on February 16, 2017, 07:35:38 PM
Half way traced it over in "the other forum" but the guy who supplied the pics dropped off the map and coudn't verify anything or get any better shots..  :P

https://www.dropbox.com/sh/adl2ow5whhueowl/AAB6MUhjESUufrqMOIXP-J2ga?dl=0

The pcb is black which makes it difficult to trace from just a picture and with limited pics and no way to verify stuff leaves a lot of guesswork... If I had one in hand I would make quick work of it.. but I don't so I am waiting for some more pics and maybe somebody to verify things on the other end..

robthequiet - That schematic is from the other forum and has a lot of guesswork on it.. may work and sound great but, it's not accurate. From what I can tell in the photos and the marking on the SOT23 they appear to be BAV99 fast switching diodes..
http://assets.nexperia.com/documents/data-sheet/BAV99_SER.pdf

Plexi

At least!
Thanks for the info
To you, buffered bypass sucks tone.
To me, it sucks my balls.

thermionix

Quote from: J0K3RX on February 17, 2017, 02:58:24 AM
"Jose Arredondo EVH modded Marshall"

You know that's a myth, right?

Plexi

This morning picked up one.
Dude... this thing is f*cking awesome!
To you, buffered bypass sucks tone.
To me, it sucks my balls.

Plexi

Which is the basic premise in this kind of high-gain pedals?

Any idea if it is inspired in some another one?

Dr. Boogie, Menatone None More Black,etc?
To you, buffered bypass sucks tone.
To me, it sucks my balls.