Omni Drive by John Hollis.Versatile pedal?

[FisTheGoon]

Hi there.I bump to this Omni Drive pedal and seem interesting .It seem could emulate alot of pedal .Does anyone have built it and could upload some sample?I want to know how it sound and if the sound is what i like .It could save me time if this pedal can do alot.
Thanks you for your time

[MartyMart]

Omnidrive is a LOT of fun - loads going for it, some very cool sounds available.
You could easily build something a LOT worse !!
From the schem, the "dark triangle" which "looks" like ground is the VB connection, or 4.5v
"Ground" is all the lower straight line connections, it makes sense as 4.5v "should" be going to
all the opamp + inputs as "normal"
Do a search as I remember some small issue/ and/or changes sugested by either Mark or Frosty ....
MM

[DDD]

Some guys from the Russian "stompboxes forums" report the following:
1. OmniDrive sounds just as Mr. Hollis says it should sound
2. The subject is very versatile pedal with lot of good sounds
3. It works very well without any special adjustments etc
4. Building this pedal "is a must" for every DIYer because its schematic is a good example of a good engineering at least.

[oldrocker]

I think I'll give this a shot.  I always like the John Hollis circuits anyways and the Omni Drive has a few things built in that I was going to build separately.  Nice to have switches and knobs to play around with too.

[oldrocker]

OK I have this built but not boxed.  All the swithces seem to working but the octave switch.  I'm getting a good sound out as fuzz and distortions go but I get no Scrambler or Octavia sounds.  I guess what's more confusing than anything is if the toggles are on or off depending on which way you switch them.  Not being boxed yet it's hard to keep track of the switch orientation.  Even without the octave working this is worth boxing up.  My dilemma is do I wait and get the octave part working first or box it without it.  If anyone has the octave working I would like to hear your opinion of it.
Opps!!  Never mind pin 1 from IC 2 wasn't in the socket.  Just noticed it.  Amazing sounding pedal.  Now I have to try adding all the LED's on the toggles.

[FisTheGoon]

Woaa.oldrocker you are fast man.So how is the sound of the pedal?Any error on the schematic or any thing that would confused the builder?
Dont mind if you could upload sample clip after you have box it?

It will be fun to build it,man.
the list of effect it can make

Distortion Device:   EH Big Muff   Fender Blender           TS-808                      SRV                       MXR Distortion+           Ampeg         Scrambler        Octavia                       Clean Boost             Treble Boost            

[oldrocker]

OK.  I'll work on those samples as soon as I can.  I finished installing the LED's.  WOW that's a lot of offboard wiring but it looks great in dim light.  I still have to label everything.  There's alot of things to keep track of on this thing. LOL!
http://www.logmonster.com/images/full/?pic=Omni1_1178292585-422-15045.jpg
http://www.logmonster.com/images/full/?pic=omni2_1178296616-422-15046.jpg
http://www.logmonster.com/images/full/?pic=omni3_1178233945-422-15047.jpg

[FisTheGoon]

Nice Leds color there.

From the schem, the "dark triangle" which "looks" like ground is the VB connection, or 4.5v
"Ground" is all the lower straight line connections, it makes sense as 4.5v "should" be going to
all the opamp + inputs as "normal"
Do a search as I remember some small issue/ and/or changes sugested by either Mark or Frosty ....
MM

there is no confusion in the schematic?

[oldrocker]

I used the schematic on the Geofex website.  So yes the John Hollis hand drawn schem can seem confusing but geo clears that up pretty well.   I'll have to find those mod suggestions you mentioned.  Thanks.
By the way the pedal sounds great so far.  There is a Big Muff emulation that would fool you if you didn't know better.  I'm still messing with the pedal so I'll know more when I find time to figure it all out.

[FisTheGoon]

By Mark Hammer  the mod

The simplest way to make the Omni-Drive feasible on perfboard is to consider dropping a
function or two and making it less ambitious.

For instance, the Mode switch simply places the clipping diodes in one of two ways,
though I have to say that this does not produce a robust difference to my ears.
I can easily live without it.  Stick D3 and D4 in parallel with the Gain pot and omit C12.
  Heck, if you want to save yourself some perfing hell, solder the clipping diodes directly
to the Gain pot.

The Blend control is also something you can conceivably scrap without sacrificing too much,
as is the Scoop toggle.  You can either keep the tone control network without R20,
or if you like the sound of the scoop, the 10k (R19) and 1k (R20) yield .9k.
  Actually, you can just sub any value between 10k and 1k for R19 to get different types
of tone responses.  Likewise, the Boost function is not especially critical.
The switch selects between a gain of x10 and a gain of x3.  Chances are pretty darn
likely you'll have far more interest in the x10 setting than the x3, so just wire up
the first stage with R4 and be done with it.  C2 strikes me as a bit small in the higher
gain setting so swap it for a .022 unit for a fuller sound.

I realize some find these functions indispensable, but I mention them simply because
they are easy to identify and omit, without changing too much, and reduce the wiring
demands by a noticeable amount.  Between the three functions we've just omitted,
we've reduced the wire count coming off the board by eight, according to my count.

So what does this leave us with?  We still hav

From:
http://www.diystompboxes.com/smfforum/index.php?topic=40347.0

[oldrocker]

Oh yes I did read that.   I wanted all the bells and whistles so I could try all the pedal emulations.  Actually at certain pot settings all the switches have a pronounced effect on the sound so I'm glad I went for it.  I edited my other comment above the last one you just posted.  The octave switch is cool too.  It's nice to have all that in one pedal.
P.S.  The clean boost and treble boost sound great.  Those were two pedal I was going to build separately but now I won't need to.

[oldrocker]

The pedal is giving me problems now.   Lots of high pitch squeal and hum when the blend pot and gain pot is turned up at all.  Very annoying.  When guitar signal is present the noise goes away and it sounds great but when I stop playing the noise kicks in and it's loud.  With the filter and octave toggles are on it's even worse.  So now I'm into the debug stage.  This may take a while since I have to watch the grand kids this weekend.

[Paul Marossy]

The pedal is giving me problems now.   Lots of high pitch squeal and hum when the blend pot and gain pot is turned up at all.  Very annoying.  When guitar signal is present the noise goes away and it sounds great but when I stop playing the noise kicks in and it's loud.  With the filter and octave toggles are on it's even worse.  So now I'm into the debug stage.  This may take a while since I have to watch the grand kids this weekend.

Check you wiring. You've got some crosstalk going on in your wiring. BTW, the Onmi Drive is something that I always wanted to build as a beginner. Maybe someday I'll build it just for fun. 

[FisTheGoon]

Wow.problems start to arise.By the way,it cool to know there is/are grandpa in this forum.

[oldrocker]

Yes,  hence the name OLDrocker. I'm getting too old for debugging. The grand kids think Grandpa is the weird scientist with all the electronic stuff all  over the place.  Not including the recording studio in the livingroom.
Thanks for the response Paul.  The wiring I have going in this pedal is more than anything I've built yet.  I don't know where to start.   Besides the noise I really like some of the sounds I'm getting.  There's one setting which I can't remember what had the coolest creamy lead overdrive.  With all the work I put into LED's and switches I won't rest until I fix this one.

[oldrocker]

I fixed it!!!   The gain pot was too big so that was one problem.(Had a 1 Meg and needs to be 470k.  I used a resistor across the pot.)  I had to move a few components and jumpers on the perfboard around to shorten some things up.  And roll off some on the tone on the guitar to quiet it down on the high end side.
This pedal is so versatile.  It's probably going to be used a lot since I can get so many sounds out of it.  Tone controls combined with filters really make this useful.  A highly recommended build.  A nice all in one pedal.  It's like The Analog Pod.  And of course the LED's are really cool looking in the dark.

[FisTheGoon]

Mr OldRocker how bout the sample clip?

[David]

Yes,  hence the name OLDrocker. I'm getting too old for debugging. The grand kids think Grandpa is the weird scientist with all the electronic stuff all  over the place.  Not including the recording studio in the livingroom.
Thanks for the response Paul.  The wiring I have going in this pedal is more than anything I've built yet.  I don't know where to start.   Besides the noise I really like some of the sounds I'm getting.  There's one setting which I can't remember what had the coolest creamy lead overdrive.  With all the work I put into LED's and switches I won't rest until I fix this one.

Too old for debugging???  NO WAY, DUDE!!!  If I can do it, you can do it.

[Paul Marossy]

I fixed it!!!

Cool! 

[Ben N]

Anybody sell an RTS board for this?

Ben