Mr Multi

[Basile]

I've just one word that came to my mind when I see your works.....


WONDERFUL

And I very impressed by your drawing.... If you wish I can make a schematic capture of your design and export it as a JPEG file! I've just one last request! If you can give us the reference of both IC, he clone will  be complete.


Well what a good job! I'm very impressive and enthousiatic about it!
One last word:


THANK YOU Eb7+9 !

P.S: I will take a moment to look at your petition,  just to give a reward to your job! See you soon!

[Eb7+9]

yeah right, the numbers might help ... the quad "741" op-amp is  uA3403 - I think the modern equiv is LM348 ... and the other is CA1458 dual "741" op-amp ...



... btw, you can likely use the same jFET and zener combinations that work in phase45/90 clones ...

(thanx for signing the petition)

~jc

[spudulike]

@Eb7+9 ... thanks for checking the layout, I've edited in the missing trace. Fantastic job on the drawings btw, cant wait to start this one.

(Oh and I signed the petition too :wink:  )

[Basile]

I've just check the PCBV and I've found one error left....A missing wire between the point and the wire!





So I've done a correction on the PCB:



I hope you like It!

See you soon!

[Eb7+9]

thx Basile

... and you removed a section of the ground so it isn't a closed loop - which I think is better ...

~jc

[spudulike]

I removed the ground section  :oops:

I think you're wrong with the edit. The trace is intentionally routed between the two pads, when it would have been easier to just directly route it ...



I thinks thats a shadow or lint which is why I ignored it ...

:?

[Basile]

i'm sorry spudulike,I don't want to make your work mine  :?  :?  :?  :?  :?

I worked on your first pcb that you have post on the firts page of the topic, that's why the ground section is missing...

For the connection between the wire and the point, perhaps Eb7+9 could check the pcb himself to see if there's a real connection or not...

I hope this problem could be fixed rapidely to avoid some troubles for me... :?

[spudulike]

I wasnt having a go, just pointing out that I had edited the pcb and that the one on the first page had been corrected.  :wink:  :wink:

Oh, and I wasnt suggesting you had pinched anything either, I posted it so that we could all check it for mistakes - it isnt my property  :oops:

[Eb7+9]

My apologies Spud and thanx for the clarification ... I'll go over it and double check one more time ...

I put down some tracks this morning to try to show what it can do in DBL-WAH foot-mode ...  essentially a deep (multi-stage) phase-filter circuit ...

http://www.putfile.com/media.php?n=MrMultiDemo merci Puretube!

I went straight into a DAW  using a bit of Limiter and Verb - no EQ ... the first part gives an idea of the sweep range and noise levels in the upper frequency range ... and the second has three gtr parts each running through the Multi along with DAW drums and straight bass ... the chords and lines in the later are from a copyrighted tune ...

~jc

[DiyFreaque]

Excellent sample!  Mr. Multi sounds good, too....

Cheers,
Scott

[Vsat]

Nice recording jc!   MM sounds good.
Cheers, Mike

[spudulike]

Ok, that does it. I have to build one of these if it sounds that good. Excellent clip, thanks

[Basile]

A big thankx to ~jc for the sound sample.... I'm really interested in this FX... I hope just one thing, ~jc could you please fixed the problem about the wire located on the PCB...it will really help us to make a really good clone!

See you soon!

Basile

[Mark Hammer]

Nice to hear a pedal featured in rhythm work for a change!

Here's a question...or maybe more of an idea.

Not to take anything away from the MM with respect to its own personality, but a footswept 4-stage phaser simply moves two notches around.  Although it is difficult to find quad ganged pots (where each pot section would substitute for the variable resistance of the FET in the phase-shift stage), and probably just as awkward to install such a beast in a wah shell for foot sweeping, dual-ganged pots CAN fit in and can be used to mimic a double notch.

Here's the plan.  If the input signal is tapped and fed to dual parallel bandpass filters - each of which can be swept via a single resistor to ground (hence controllable via a dual-ganged pot) - and then fed to a mixing stage where these filter outputs are out of phase with the original/clean signal, what you'll have are two notches.  The notches are easily staggered to any desired spread, and their Q can even be easily individually adjusted and levels balanced.

The filter sections can either be of the type found in the Bi-Filter Follower ( http://www.generalguitargadgets.com/diagrams/cabff_sc.gif ), or the type found in the Dr. Q (Dr. Quack, Nurse Quacky).  Hell, they can probably even be one of each for all I care.  The point is that each is tuned by a single resistance to ground.

Do you want to get wickedly interesting?  Consider this conception:

1) After the input stage (can be a unity gain buffer OR add a bit of gain, your choice), signal goes to an op-amp mixer, and to two bandpass filters.

2) Each filter can have range selectable via cap choices, and Q/resonance tunable via a feedback resistor.

3) Each filter goes through a bypassable unity-gain inverting buffer.

4) Each filter path gets mixed in to mixing stage via its own level pot.

5) Sweep of filters is controlled via a dual-ganged pot.

What can you do with this?  Well, for starters, you CAN mimic the dual-notch sound of a phaser by feeding inverted filter outputs to the mixer.  The stagger possible from selecting the range of each filter can achieve different phaser tones.  The variable resonance and level can also vary the phaser tone, and completely fading out one filter at the mixer will mimic a 2-stage phaser.

Of course, feeding a filter signal to the mixer that is in-phase with the original will produce a peak.  Since the bandpass is added to a full-bandwidth clean signal, it will be a more balanced sound than a swept bandpass type wah.
But wait!  There's more!

Since this plan allows you to invert the two filters independently, you have the option of sweep a peak AND a notch simultaneously.  One can be higher or lower than the other, and their spacing and dominance can also be altered.

Is that flexible enough for you?

I have this wah shell just sort of sitting around.....hmmm......and in principle it only takes 6 op-amps, one dual-ganged pot, and two level adjusting pots.

[moosapotamus]

Wow! With all that cool sweeping going on, perhaps stereo outputs would also be in order? :mrgreen:

~ Charlie

[Mark Hammer]

Oh...so "Mr. Complicated" is gonna stamp his feet and hold his breath until someone adds sum/difference stereo outs and re-assignable filters?  Okay, okay, you big baby.  There you go.  Are you happy now? :lol:  :lol:

Good lord, we are sick puppies.  Somebody gas this entire animal shelter pronto, before we hurt someone! :lol:

[Eb7+9]

Nice to hear a pedal featured in rhythm work for a change!

I was kinda hoping you'd chime in Mark ... you've obviously given these types of circuits lots more thought than I have ... it sounds good on single lines too - as long as you feather the picking, same as with a phasor ... the idea of using Vibe-ratios in the shifty circuits came to mind too but it's pretty good as is ... I sure do look forward to checking out a complete schematic of your idea ...

~Charlie, as usual your recomendations fired my thinking ... my feeling is the best way to do a stereo version on this puppy would be to have the circuits duplicated entirely and controlled by a double-pot each wired in opposite direction ... may have to stick a buffer or two at the input to prevent cancelling/loading in the return paths to the front end ... I imagine it would be *VERY* thick sounding ...

Thnx to all for checking out the clip and giving comments ... I got band practice today so I'll be poop-du-jour by tonite ... I promise I'll go over the PCB art with a fine-tooth comb tomorrow and will get back with my stamp of aproval so y'all can start etching ...


~jc

[Mark Hammer]

Incidentally, during a lull in class, I was sketching, and it occurred to me that anyone who may have already built the Anderton BFF could probably mount the circuit in a wah shell, and simply use the foot treadle to control the Initial Frequency pot.  You might have to tinker with the taper or the fixed resistors on each side of the pot, but it would work.

It also occurred to me that if one used transistors as control elements as in the Baseballs, a single pot could also be used to foot-sweep two filters simultaneously. Ciombine those filter outputs with a straight signal and you'd have something like the Mr. Multi as well.

Finally, I said it would take 6 op-amps.  I was wrong.  The BFF-type bandpass filters are inverting.  All one would need to do is direct their outputs to the noninverting or inverting inputs of the mixer stage to get notches or peaks.  I should have remembered that. :oops:

[moosapotamus]

Oh...so "Mr. Complicated" is gonna stamp his feet and hold his breath until someone adds sum/difference stereo outs and re-assignable filters?  Okay, okay, you big baby.  There you go.  Are you happy now? :lol: :lol:

... I also want an effects loop, LFO/CV input/output so I can sync my moogerfooger, LED's fo visual LFO rate indicators, tap-tempo, auto-morph between the three different modes...

... my feeling is the best way to do a stereo version on this puppy would be to have the circuits duplicated entirely and controlled by a double-pot each wired in opposite direction ... may have to stick a buffer or two at the input to prevent cancelling/loading in the return paths to the front end ... I imagine it would be *VERY* thick sounding ...

OK... now who's "Mr. Complicated"?    

BTW - Very cool sounding clips, jc! I can see/hear why you wanted to rev this one, too. Don't you ever sleep? :wink:

~ Charlie

[Paul Marossy]

So, is there a finalized PCB layout yet? This one looks interesting enough to build. Uh oh, I'm on a wah kick these days!  :lol: