MUFF WIGGLER Forum Index
 FAQ & Terms of UseFAQ & Terms Of Use   Wiggler RadioMW Radio   Muff Wiggler TwitterTwitter   Support the site @ PatreonPatreon 
 SearchSearch   RegisterSign up   Log inLog in 
WIGGLING 'LITE' IN GUEST MODE

Concept test - CP3 mixer with input VCAs.
MUFF WIGGLER Forum Index -> 5U Format Modules Goto page 1, 2  Next [all]
Author Concept test - CP3 mixer with input VCAs.
Rex Coil 7
Kicking around an idea.

I've spent ... (well, actually) ... too much time looking into this, and I just cannot find what I want. So I'm faced with buggin' the goodfolk here in the 5U subforum. I'm starting here in the 5U subforum because I feel as though I identify with most folks in here.

HERE'S THE CONCEPT:

I have a Suit and Tie Guy CP3 mixer (5U, obviously). As it stands, it is a fine rendition of a venerable audio mixer. I've done some goofin around with placing VCAs in front of the input channels of said mixer. As those of us that own any incarnation of the Moog CP3 mixer already know, the CP3 mixer responds very well to channel input levels. That said, using an input level VCA at every channel would optimize the CP3 and "complete the story" of the CP3 where it seems as though it was cut short. This hot rod of a mixer would work so much better if it only had a set of wheels! It seems that far under-completed, especially when you try using VCAs on the inputs and you hear what it's true potential can be.

Running 2, 3, or even 4 VCOs into it, each one going through it's own dedicated (and modulated) VCA makes for some really *FAT* sounds. The synth seems to come to life.

Long made short, this needs to be ~a thing~ .... it needs to happen!

Using manual modulators (wheels, ribbons, expression pedals, perhaps even a 4ch joystick such as the Intellijel Planar) may be used to sweep through "vectors" and change the mix of the VCOs, each one with it's own setup (perhaps different waveforms, different octaves, and so on). Of course, this has been done time and again with 4 channel VCA Mixers. But not with VCA CP3 mixers! At least not anything commercially available, not even as a set of DIY PCBs. And at least not as far as I have found.

Even a single VCO with a VCA in front of the CP3 is what could be considered a "power adder" ... in that it turbocharges the sound! Modulating the VCA with an LFO makes one VCO sound like two (or like PWM) as the VCA controls a gentle swell~fade of the input signal strength. This makes the CP3 go from gently distorting to clean, and back again ... over and over. Using an Envelope Gen to control the input VCA is also very nice, even with just a single VCA/VCO. It ~almost~ sounds like subtle wavefolding depending on the VCO waveform used.

DESIGN THEORY:

Here's the design theory (based on a proposed 4 input channel VCA CP3 Mixer); On each input channel, discard the regular input attenuator. Replace the attenuators with individual VCAs (4 channels = 4 VCAs). Each VCA needs to have very simple controls, just one "GAIN" pot, and one "CV LEVEL" pot. Add an On/Off toggle switch so switching each VCO on and off is easy and quickly done (just like a Minimoog). The on/off toggle also supports being able to set up gain and CV levels on each channel, while being able to cut or add each VCO to the mix without disturbing the gain/cv settings you took the time to set up.

So pretty much slice off the input pots (I'm refering to the schematic now) and replace them with VCAs. All else in the basic CP3 design remains the same as the original design ... pretty much. Adding a master output level control is optional and up to the individual end/user. However if a master volume is required, let's go big! Install two of them, each one being attenuverters (ccw = negative ... cw = positive).

Ok then .... I believe by now I've conveyed the idea.

QUESTION:


I need to locate simple, clean, DIY VCA circuits for use with this mixer. The Oakleys are too bulky (no mud slung at Tony here ... his VCAs are top notch, but the PCBs just too large to wedge 2 of the dual VCA boards along with CP3 circuitry under a 2sp panel).

The VCAs don't need to have a lot of tricks or features to their design:

** Gain level pot.
** CV signal level pot
** CV signal input.
** Audio signal input.
** Audio signal output.

** Add an audio signal on/off toggle for each channel, like a Minimoog.

The only reason the ~gain~ pot is required is so each channel may be manually set (y'know, just like a regular mixer) in the event CV modulation isn't required. A gain control may also be helpful to set a gain floor, to permit the CV signal to vary the gain, but allowing it to go no lower than the pre-set floor. I suppose the gain control could be referred to as "gain offset" as well, while the CV control could be thought of as setting the "modulation range".

Any help on this? The plan is to hopefully design all of this on to a single pcb and execute this bitch! I'm figuring (as a module) it will take up 2sp of MU, which I'm ok-fine with. Two stacked pcbs is fine (Dot Com style standoff mounting, placing one atop the other) ... if it comes to that.

15v power is also required, but a 12v to 15v circuit would be ideal (lookout Euro party, here I come!).

EPILOGUE:

I realize this concept isn't anything groundbreaking, however it does not seem to be anything offered commercially (~ahem~ ... yet). I'll admit that I'm sure I didn't scour the entire planet for VCA circuits, so I may have missed something ... easily so.

If there isn't some type of ready made ensemble, I am quite willing to give this a whack. In another life, I've designed ~roughly~ a dozen PCBs from circuits of my own design, so I'm a little bit familiar with how to go about it.

I already have some ideas for various options that the builder can adopt ... involving some of my recent adventures with ring modulators.

hihi (I don't know SHAT about no damned ring mod ideas ... that's my story and I'm stickin' to it!) Mr. Green

Soooo maybe ...

Depending on if/how it all shakes out, and if there is enough interest, I may even be coerced into providing them for sale ... Bare or Populated PCBs (12v or 15v), Panels (Euro and 5U), and if someone is really nice to me, maybe even full-on completed units in Euro or 5U ... maybe. (wink).

cool
Rex Coil 7
Now that I took all of that time to author this thread's opening post, I've been locating a few VCAs that may actually do the trick.

Link = http://www.mattsonminimodular.com/shop/index.php?main_page=product_inf o&cPath=1_2_14&products_id=31

Link to thread by George Mattson about the above Quad VCA =
https://www.muffwiggler.com/forum/viewtopic.php?t=18334

Not sure if it will run on 15v though (still reading up on it). thumbs up
Rex Coil 7
Damn it already! I looked for a few days (on and off) and I couldn't find a suitable multi channel VCA if I was sittin' on it!

So I post this thread and now they're jumping off the ground into my lap!

Here's the Barton 4ch ... runs on 15v. We may have a WINNAH here folks.

Checkered Flag applause

Link = http://www.bartonmusicalcircuits.com/vcamix/documentation3.1.pdf

GEEZ!!! seriously, i just don't get it d'oh!
Eric the Red
After reading the first post, I was going to recommend the Barton - super easy build, I’m making 10 of them smile
JohnLRice
Rex Coil 7 wrote:
Now that I took all of that time to author this thread's opening post, I've been locating a few VCAs that may actually do the trick.

Link = http://www.mattsonminimodular.com/shop/index.php?main_page=product_inf o&cPath=1_2_14&products_id=31

Link to thread by George Mattson about the above Quad VCA =
https://www.muffwiggler.com/forum/viewtopic.php?t=18334

Not sure if it will run on 15v though (still reading up on it). thumbs up
George mentioned long ago here: http://mattsonminimodular.com/forum/viewtopic.php?t=117
Quote:
Most of my circuits seem to be perfectly happy using +/-15VDC or +/-12VDC.


George is a friend and does excellent work! thumbs up He is in the process of moving right now so it might be a while before he gets back to you if you try to contact him.
Synthbuilder
Rex Coil 7 wrote:
Here's the Barton 4ch ... runs on 15v. We may have a WINNAH here folks.


Might not be a problem but it has only a 4K7 input impedance which is quite low. Also, the input is a standard non compensated OTA so it will respond non-linearly - not that is a bad thing but it can distort waveforms if you drive it too hard. The Moog Voyager's VCO waveshaper 'suffers' from this giving it a somewhat dull sound on the sawtooth. It does give a nice tone to the triangle though.

A single LM13700 stage, in particular when used to create a voltage output, is also a tad noisy. Again not really a problem for waveform mixing.

Tony
Rex Coil 7
Synthbuilder wrote:
Rex Coil 7 wrote:
Here's the Barton 4ch ... runs on 15v. We may have a WINNAH here folks.


Might not be a problem but it has only a 4K7 input impedance which is quite low. Also, the input is a standard non compensated OTA so it will respond non-linearly - not that is a bad thing but it can distort waveforms if you drive it too hard. The Moog Voyager's VCO waveshaper 'suffers' from this giving it a somewhat dull sound on the sawtooth. It does give a nice tone to the triangle though.

A single LM13700 stage, in particular when used to create a voltage output, is also a tad noisy. Again not really a problem for waveform mixing.

Tony
*Tony, thank you for your insights on this project. So you know, your offerings aren't out of contention just yet, as long as I can work through some mechanical engineering issues. It comes down to a matter of being able to stack them on standoffs, while still leaving room for the CP3 board. Best I can figure, I'd require two of your Dual VCA boards, stacked on standoffs, with a third "layer" being the CP3. In and of itself a module with 3 PCB layers isn't a problem, as long as it will fit in my synth. The available space between the rear surface of a panel to the "normalizing rail" I have mounted in my particular synth cab comes to ~roughly~ 4.5". That said, we have about 4.00" of comfortable depth available, by 4.00" of comfortable panel width available, by 5.00" or 6.00" of comfortable height available. If the whole works can be fitted inside of that 4"d x 4"w x 5"/6"h ~virtual cube~, using Oakley VCAs may work out.

... OR ...

Perhaps using the method of mounting PCBs that you adopt may work, as long as the two VCA boards would be placed close enough together to create enough space to mount the CP3 board in the same manner ... all fitting within the same ~virtual cube~ of available space.

What do you think? seriously, i just don't get it (by the way, I'm also thinking of using the ODII circuit between the CP3 output and the VCF input, but that is a totally separate issue from this proposed project).

***********************************************************

@*John ... yea, I saw on George's website that he's "reorganizing" and will be back in service at the end of May. The PCB size and configuration most certainly work (from a mechanical engineering sense) as far as fitting it into this idea. The board and the wiring kit total up to $142.00, for a totally prebuilt PCB and flying leads with the AMP (Molex?) connectors all made up and fit for duty!

Board Link = http://www.mattsonminimodular.com/shop/index.php?main_page=product_inf o&cPath=1_2_14&products_id=31

Cable Kit Link = http://www.mattsonminimodular.com/shop/index.php?main_page=product_inf o&cPath=1_3_17&products_id=61

I'm super glad to learn that the Mattson circuits operate on 15v power. I suppose if I explain to him what my intentions are that he may take it upon himself to optimize the PCB for 15v power.

***********************************************************

Also, that L1 quad VCA looks mighty tasty! I'd need to configure it for use with 1/4" jacks, large B100k pots, and flying leads ... but that doesn't appear to be too awfully difficult. In this thread, "Alex" speaks of how to configure the L1 for 15v power (part of the reconfiguring includes the use of B100k pots, ironically so).

Link to L1 thread = https://www.muffwiggler.com/forum/viewtopic.php?t=92654&highlight=

***********************************************************

Another alternative: I could also make speaks with Dr. Sketch-n-Etch about the entire project, and see if he is interested in making up a prototype that would involve 4 VCAs and a CP3. ("paging Dr. Dave, you're needed on the psychiatric floor at once!")

lol

So there are more options than I first thought. I honestly feel this is worth pursuing. Just from manually manipulating the input level controls of the STG "Mixer" (his CP3 clone) with a few VCOs running into it really prove the point. I'm going to try using a few waveform outputs from a single VCO into the STG CP3 to see how that will work. With my oddball dual VCO rig, I have the capability to boost the triangle and sine waves so they match the Saw and Pulse outputs (I'm speaking of gain levels here). This way I can test the whole concept with one VCO to see what it might do for a single oscillator rig. If it does that "wavefolding-slash-pwm" thing well enough, it may just become yet one more asset which supports this whole idea.

Thanks for the very helpful and solid input folks.

Enough blabber .... work to do!

thumbs up
Dave Peck
Another option , if you don't want to assemble your own circuit boards from scratch - there are plenty of really cheap dual, triple, and quad VCA modules available in Euro format and many of them will work fine when powered by +/-15V. You could get one of them, discard the Euro panel and cannibalize the complete board assembly.
Rex Coil 7
Dave Peck wrote:
Another option , if you don't want to assemble your own circuit boards from scratch - there are plenty of really cheap dual, triple, and quad VCA modules available in Euro format and many of them will work fine when powered by +/-15V. You could get one of them, discard the Euro panel and cannibalize the complete board assembly.
That's not a bad idea. I suppose all it would take is some research, right? I have NO problem cannibalizing (just look at what I have already done!).

I'm looking pretty hard at the Mattson Quad VCA right now. That change of heart comes from what Tony said about the Barton, it made a lot of sense. I have no idea what the input impedance of the Mattson is, but I suppose it's something I can find out. $110.00 bucks gets me a completely populated and calibrated Quad VCA board that has Dot Com style AMP 0.1" headers on a 3.125" x 2.650" PCB that's set up for standoff-type mounting. One negative I know of at this point is that the Mattson has no provisions for CV level attenuators on the board. This may not be an issue, however. Pic:



If I knew I could get the Oakleys into place while leaving enough room for the CP3 circuit the choices would include the Oakely Dual VCAs. But I'm just not convinced 2sp of MU is enough for everything.

Like most things in life, there are positive aspects, and negative aspects to all choices ... in this situation I currently see 3 (cheap and quick Euro VCAs, the Oakleys, and the Mattson) ... it all comes down to which set of negatives I'm willing to tolerate to obtain their positives.

I am trying to juggle a few problems, with 6MU to work with. I would actually have 3MU spaces available for this particular project (which would pretty much guarantee the Oakleys a job) but I don't know if I can get away with only using 1MU for another issue. If that other issue can be reduced to needing only 1sp, then I can give the extra space to the VCA/CP3 project so it has 3MU spaces to work with.

So you better believe it when I say "I've got my construction paper, scissors, pencils, steel ruler, and camera out" on this one. (That's a reference to how I go about designing module panels). I'm doing everything I can to juggle around a total of 6MU spaces seeing how they'll be allocated to four separate issues.

In the order representing signal flow (left to right):

** Panel = External Signal Input panel.
** Panel = Ring Mod mixer controls for 3 ring mods plus sends/returns for 4 VCOs.
** Panel = The Quad VCA/CP3 thingy.
** Panel = A signal distributor for the input of the Dual VCF panel.

I have 6MU spaces to work with to address all of that. hmmm.....

The Ex.In. panel can be made in 1MU. The signal distributor for the Dual VCF module can be made in 1MU. That leaves 4MU left to allocate to the RM mixer/VCO sends and returns ... and the QVCA/CP3. If I can actually distill the RM Mxr/VCO send-rtrn down to 1MU, I'll have 3MU to work with on the QVCA/CP3.

My work is cut out for me. hihi

CHOICES!!! d'oh!
Rex Coil 7
HOLD UP ... just hang on here a second: I may have just worked this out.

The 2MU panel that isn't the QVCA/CP3 module won't use any circuit boards. It's alllllll just toggles, jacks, and 4 pots, no boards.

That said, maybe I can work it all out so that I can combine the RM mixer controls, the VCO signal Send/Return jacks and routing toggles ... with ... the 4VCA/CP3 circuit boards and controls/jacks.

HA!!

A 4MU panel that deal with all of those needs. By putting it all on one single 4MU panel, I can distribute things a bit ... spread stuff around ... make room for those PCBs. As long as I mount them boards high enough off of the panel surface, I'll have space to put components under the boards (Dot Com style).

HA! This just might work!

Now, where's my scissors and construction paper at ... I have an idea to work out!!

thumbs up
CZ Rider
Since it is Bob Moog day today, May,23. Here is one Bob made back in 1970.



Bob did many custom modules, this one was for the CEMS.


An interesting voltage controlled mixer, as it is made up of existing modules. Behind the panel are four 902 VCA boards and a CP3 mixer.
Can see the familiar 902 board here.


All four boards are sandwiched together and wired via the 22pin edge connectors.



Can see the small CP3 board mounted in the middle here.

The CEMS ( Coordinated Electronic Music Studio) did not have a keyboard controller, but used several custom joysticks, along with eight 960 sequencers. This would be a fun module to clone, but four 902's and a CP3 might be more "modular" in the various configurations one could patch. Still an interesting idea.


Happy Bob Moog Day!
Rex Coil 7
Leave it to a Ducati rider to have pics of a little known Bob Moog experimental quad VCA/CP3 mixer ... on Bob Moog Day no less!!

That thing is beautiful. As you said, a fistful of patch cables would be needed.

Fortunately this Frankenmixer I'm working up will be mostly normalled on the ins/outs, the CV I/O will also be normalized with switching jacks to defeat the normaled back panel connections.

I just spent the last two hours looking up the parts list for the Oakley Dual VCA. Since I have no intention of using it as a "mixer" (per se) it will be configured as two Dual VCAs instead of the "master/slave" Quad VCA/Mixer configuration. That said, the parts I don't already have in stock come to $29.00 bucks per Dual VCA. (I had every single resistor on hand ... all 1% metal films, even the 2M2 ... I am SO fekking cool!). Add the two boards ($35.00 Sterling x 1.4) at $49.00 USD for the pair, and the two populated boards will end up running me ~roughly~ $110.00 USD. That price does not include any of the socket board stuff, or the interconnecting cable that interfaces the two boards for the Quad VCA configuration, or the power input headers. I plan on soldering the power wires directly to the PCBs, which removes yet one more termination.

Keep in mind I'm using bus bars with #8 eyelets. My synth will be configured to remove modules by doing most of the work from the rear of the synth. That said, I'll have superlative access to the bus bar connections, as well as any CV wires that are connected to the terminal strips inside. Said another way, all servicing is to be done from the back of the synth cabinet. That said, having "quick connect" power cable headers is unnecessary since accessing the CV connections must be done from the back anyhow.

Ironically, the Mattson Quad VCA board is $110.00 USD (granted, that is for a populated one ... and $32.00 bucks worth of connection cables with AMP connectors need to be added to that price as well). Yea, but still ... pretty danged close. One thing that the Oakleys have in their favor is they have CV amount pots, the Mattson does not. One other little bug-me of the Mattson is it doesn't use IC sockets. I like IC sockets, especially the machined type ... which I have plenty of on hand in 1, 2, 3, 8, 10, 12, and 14 pin configurations. On the other hand, in the Mattson's favor is it's small size (3.125" x 2.650") compared with the Oakleys which are ~roughly~ 4" x 5" (99mm x 125mm) ... and their are two of them.

That fact makes me wonder what the Mattson is missing to make it so small .... or said another way, what do the Oakleys have going on that make them so much larger? The combined dimensions of the two Oakley Dual VCAs is ~roughly~ 8" x 10" ... compared to the Mattson Quad VCA at 3.125" x 2.650". I don't know what to make of that. Could be that the Mattson uses quad opamps vs the Oakley using twice as many dual opamps, plus whatever extra circuitry is involved with having CV depth controls, as well as the AC/DC coupling toggle circuitry ... uhm, and the fact that the Oakelys are also mixers with summed outputs and the added circuitry there as well ... (maybe?). Wow, ok after reading what I just wrote, there is quite a bit more going on with the Oakleys that could account for their "plus size" dimensions.

So torn. Oakley? ... Mattson? hmmm.....

As far as the CP3 PCB is concerned, I can use the Mahattan Analog "DTM" board ("DTM" = Discrete Transistor Mixer). I read last night that the DTM board may be used with either 12v or 15v power.

Link to DTM thread = https://www.muffwiggler.com/forum/viewtopic.php?t=91461&highlight=

For $10.00 whole bucks I can haz the CP3 board. Less the components, obviously.

Link to Manhattan Analog DTM page = https://manhattananalog.com/products/cp3-dtm?variant=33847819014

Put the CP3 with one of the Quad VCA choices together, we can haz a Voltage Controlled CP3!! I cannot wait to decide on a VCA circuit so I can get to work on the prototype. I still want to believe that melding it all together into a two-PCB kit (boards only) is a worthwhile idea. If I can work out the quad VCA thing, I'd be more than happy to do up two-dozen pairs of boards to make them available to the community. Obviously, being as careful as careful can be to make certain no-one's circuit designs or artwork are violated in the process.

Clearly I wouldn't be making much moolah on the offering, it would be just a bit of a service provided to this wonderful community that has shown me nothing but support over the years. I'll even work up a Front Panel Designer file and provide it for free (inspired by Tony Allgood).

As long as all of my expenditures are covered, I'd add just enough markup to be able to offer free shipping ... so customer purchases are easy and hassle free.

I love this idea. Simply too cool.

Happy Bob Moog Day ... indeed!

thumbs up

EDIT: I may end up naming it the 523 VoltCon MXR ("523" = Bob Moog Day) ... the rest of the name inspired by .................



thumbs up thumbs up thumbs up thumbs up thumbs up thumbs up thumbs up thumbs up thumbs up thumbs up thumbs up thumbs up
Synthbuilder
Rex Coil 7 wrote:
what do the Oakleys have going on that make them so much larger?




It's all about the getting the board mounted pots and sockets in the right place for the complete module. If it were to be done so that all the pots were externally mounted and wired with small looms, dotcom and Mattson style, then it could be a lot smaller. The Oakley one also has the mixer function.

George's design looks like Mike Irwin's excellent linearised 2164 VCA. A high quality VCA with low noise. If this one is built in the usual way they will be less noisy (wideband hiss) than mine but will exhibit slightly more CV breakthrough.

Tony
Rex Coil 7
Synthbuilder wrote:
Rex Coil 7 wrote:
what do the Oakleys have going on that make them so much larger?


George's design looks like Mike Irwin's excellent linearised 2164 VCA. A high quality VCA with low noise. If this one is built in the usual way they will be less noisy (wideband hiss) than mine but will exhibit slightly more CV breakthrough.

Tony
lol lol Dang it Tony ... you're not making this decision any easier!!! lol lol

Your VCA boards are super nice! There's absolutely no doubt about that!

I gotta ask ... have you ever entertained doing something as I've proposed here in this thread? You already have a filter (I think) that has a three channel CP3 built into it. The Discrete Ladder Filter ("DLF") I believe.

Link = http://www.oakleysound.com/dlf.htm

Had I not already invested in a pair of other filters and spent countless hours developing a Front Panel Express panel for them, your DLF would be my choice .... adding VCA input channels to it, of course.

hihi

Ugh .... I'm still bouncing back and forth between the Oakleys and the Mattson. However, it may turn out that I don't have a choice, I've read a comment in forum by George that he is "officially retiring" sometime during May .... THIS May.

So I'll have to see how it all irons out.

Meanwhile, I'm carrying forward with completing the QX500 Dual Filter Multi Circuit panel. I'm currently smoothing out the wrinkles in the SIXTH iteration of that design.

hmmm.....

Hey, I never said I knew what I was doing!

spinning Smash!
Synthbuilder
If space is a premium and you're hand wiring the pots on a custom panel go with the Mattson.

Rex Coil 7 wrote:
have you ever entertained doing something as I've proposed here in this thread?


I'm more of a 'split each module down into the smallest component' possible sort of designer. So a voltage controlled mixer should be just that. Nothing extra added. So following this reductionist train of thought if one needed CP3 style voltage clipping and wavefolding then a separate CP3 circuit should be used. Since several of these exist I didn't see any point in adding an Oakley one.

Now the CP3 circuit I added to the DLF 904A clone was indeed a bit of a break from tradition. A filter with a built in clipper/wavefolder - but there was space on the PCB and it fitted in with the usual CP3 to 904A combo so often used. Plus I had just been fixing a big Moog Modular and although I wasn't go to do another Moog ladder module, the 904/CP3 combination piqued my interest. I didn't add any mixing capability to the suggested single width panel design though. Any mixing was to be done outside the module.

I do have an asymmetrical clipping mixer in the Oakley Fourmix but it's not voltage controlled. It's much more subtle than an overdriven CP3 though.

As an aside I started off designing big one off synths that could do a lot but had no patch cords but switches and pots. That changed when we had the first UK Synth-DIY meet in the late 90s and I got to play with a real Digisound modular. It was a like a musical Denshi Block set.

But I'm back designing a complete synth at the moment. It's called the Mysterious Audio Plaything (MAP) but it's more of a droney, ambienty sort of thing rather than a standard synth.

Tony
Rex Coil 7
Ok ... I've made up my mind and have corresponded with Tony Allgood at Oakley Sound to arrange purchase of 3 Dual VCA boards. This project turned into a SIX channel mixer, it also helped to simplify some issues. I've pretty much designed the FPE panel (with just a few small additions needed, such as the holes for the PCB standoffs ... I won't know about those dimensions until I receive the boards from Tony there in Old Blighty (England).

... And did those feet ... in ancient times ... walk upon England's mountains green ...

Oh hell ... sorry, I got distracted. hmmm..... lol

So I'm going Oakley on the six VCAs, and Manhattan Analog on the CP3 board (it's a steal at $10 bucks!). I've created a "project" in Mouser for the parts I need to build three Oakley Dual VCAs (the "project" is for one PCB, so I'll order three of those projects). Each Dual VCA project comes to $29.00 bucks .. so for three complete boards it will run me just under $100 bucks for the parts, plus $90.00 for the three Oakley boards (that's after the currency exchange rate applied). So it totals out at about $190.00 for the three Dual VCA boards. That's only about $64.00 for a Dual VCA (or $32.00 per VCA board). Add the panel ($105.00) and we're at a totally totaled total right around $300 .. or $50.00 bucks per VCA. That's reasonable, all things considered!

I've also created a "project" for the Manhattan Analog "DTM" (Discrete Transistor Mixer). I have a lot of the DTM parts on hand already, I even have the 3906 and 3904 transistors on hand (!!!).

Here's the rough-out of the panel. I've named this module the "VOLTCON" in honor of Bob Moog's VCA fed CP3.



CZ Rider wrote:
Here is one Bob made back in 1970.





Hmmm ... it may end up being called the "VOLTCON 70" .... seriously, i just don't get it

thumbs up
Schlumpfhut
Quite an interesting project. I'm curious to see how it will progress. Would you be willing to share your FPE design and the mouser projects in the end?
Rex Coil 7
Schlumpfhut wrote:
Quite an interesting project. I'm curious to see how it will progress. Would you be willing to share your FPE design and the mouser projects in the end?
Absolutely! nodnod spinning Hug
Eric the Red
Your projects always surprise, inspire and amaze me.
SynthBaron
Someone should make little CP3 mixer PCB's, with the special voltage regulators, that you can add to any module with an audio input. Add a bypass switch and spice up any signal chain!
milkshake
SynthBaron wrote:
Someone should make little CP3 mixer PCB's, with the special voltage regulators, that you can add to any module with an audio input. Add a bypass switch and spice up any signal chain!


I'll take a couple of those. SlayerBadger!
Paradigm X
thats basically the Manhattan analog pcb. ive got two, built one, sounds great (not that ive heard the originals)
OurDarkness
Is the Minimoog's mixer a CP3 mixer? If not, what are the differences? hmmm.....
Flareless
Eric the Red wrote:
Your projects always surprise, inspire and amaze me.


Freak me out is what they do! SlayerBadger!
kindredlost
Yeah I have a couple of the MA CP3 mixers and they are similar to the STG Mixer. I also have an eight channel VCA from Synthetic Sound Labs to pair up if ever this idea became necessary. Your project is interesting Rexcoil7 but the complexity of the panel graphics is making me dizzy.
MUFF WIGGLER Forum Index -> 5U Format Modules Goto page 1, 2  Next [all]
Page 1 of 2
Powered by phpBB © phpBB Group