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Thanks anyway. Tremendous job

Damn, man. Thanks for the effort.

Now that's a seriously righteous post! Thanks!

I'd love to see something like this on the mooger delay.

Not a single SMD! Holy shit.

Some missing informations:

U5 CD4024BE: 7 (0V), 14 (+9V)
U6 HCF40106BE: 7 (0V), 14 (+9v)
U7 LM337AN: 12 (0V), 3 (+9V)
U8 TL072CP: 4 (-9V), 8 (+9V)
U9, U10, U15 LM13700N: 6 (-5V), 11 (+5V)
U11 CD4053BE: 8 (0V), 16 (+9V)
U16-21 LM13700N: 6 (-9V), 11 (+9V)
U14 LM324AN: 11 (-9V), 4 (+9V)

Some great initial postings! One question: do RN4_1 through RN4_4 (470Rs connected to U10) connect to ground?

celadine wrote:Some great initial postings! One question: do RN4_1 through RN4_4 (470Rs connected to U10) connect to ground?

Thanks for your observation! You're right!
Here is the updated schematic.

Has anyone actually achieved a clone of this mammoth schematic? Well done if you have it's not for the lite hearted

Ignoring the virtues of a working pcb layout, I would be inclined to build this on veroboard. Once the component pattern is established for working filter sections around one dual OTA, it should be easy to copy for the other 5.

Ideal for a rack mount unit!

Yeah that's a good point. At least the vero board would give you room to breath if something wasn't quite right in it. and if you socket everything in the way of semiconductors it would give a good platform to work off. I've never been a big fan of breadboard's especially with larger circuits. To much chance of high resistance joints with things not making contact properly and wires and components falling out. Vero is much better for prototype.

You guys rule, thank you very much! I've got one of these and want it to put out more high end and sound better overall, but never managed to trace the schematics myself.

Hello,

I've checked the schematic and found it is ok up to a small detail concerning the connections to the "positive" VCA output. RN3-2 should be connected to RN3-3 and PIN 3 of U10A what is the positive input VCA.
In the schematic RN3-2 is connected RN3-3 and R34 and so we short input and output of the allpass filter.

Something important I could not guess from the pictures and what is not written on the schematic is the supply rails of the different OTAs in the allpass cells and VCA. Could some-one give a hint?

Thankyou

alain-mac wrote:Hello,

I've checked the schematic and found it is ok up to a small detail concerning the connections to the "positive" VCA output. RN3-2 should be connected to RN3-3 and PIN 3 of U10A what is the positive input VCA.
In the schematic RN3-2 is connected RN3-3 and R34 and so we short input and output of the allpass filter.

Something important I could not guess from the pictures and what is not written on the schematic is the supply rails of the different OTAs in the allpass cells and VCA. Could some-one give a hint?

Thankyou

raindog wrote:Some missing informations:

U5 CD4024BE: 7 (0V), 14 (+9V)
U6 HCF40106BE: 7 (0V), 14 (+9v)
U7 LM337AN: 12 (0V), 3 (+9V)
U8 TL072CP: 4 (-9V), 8 (+9V)
U9, U10, U15 LM13700N: 6 (-5V), 11 (+5V)
U11 CD4053BE: 8 (0V), 16 (+9V)
U16-21 LM13700N: 6 (-9V), 11 (+9V)
U14 LM324AN: 11 (-9V), 4 (+9V)

There is the supply rails... isn't traced the actual pedal supply but you can figure out from here.

Thanks,

exactly what I was looking for.

I don't know why I didn'y see it sooner....

I've incorporated the "sweep" control on a personal phaser and it's a really nice simple thing to add to a phaser (need a pot , a op-amps and few resistors)

Hey Devastator!

Off topic: are you the same Devastator that I had met on techniguitare years ago?

I'd like to give the sweep pot a try, in the ROG trivibe or in a EHX small stone, and I have several questions.
As far as I can see, the sweep control in that configuration consist in an adjustment of the central frequency of the sweep, is it correct?
Is there a way to "enlarge" the range the sweep (extend the corner low and high frequencies of the LFO) with another pot?
Are Q6/R73/R74 and Q7/R75/R76 needed? Or do I "only" need to connect the output of the added op-amp to the "LFO in" on the OTA?
I came across several phaser designs, particularly in synth circuits, that have that kind of network, like the ARP Quadra phase shifter or the Aries Model 329 Phase Shifter.
Some of those designs, and the Jet Phaser also have a "bias" trim, kind of directly connected (without opamp) to the LFO output, that also seems to act as sweep adjustement. Do you think this simple design may also be a solution?

I realized most of my questions are irrelevant. But I can't edit my post...

Devastator, if you come to read this, could you tell me (us) how do you adapt the "sweep" control to make it fit in a random phaser, please?

loylo wrote:Hey Devastator!

Off topic: are you the same Devastator that I had met on techniguitare years ago?

yep I'm , I'm even "fuzzo" at PG5 .

As far as I can see, the sweep control in that configuration consist in an adjustment of the central frequency of the sweep, is it correct?

yes , it moves the "focus" of the phase effect on frequencies. Sorry , it's not a really technical way of saying things. You can get the technical explanation on the moog phaser manual (the moog manuals are really great ! )

Are Q6/R73/R74 and Q7/R75/R76 needed? Or do I "only" need to connect the output of the added op-amp to the "LFO in" on the OTA?
I came across several phaser designs, particularly in synth circuits, that have that kind of network, like the ARP Quadra phase shifter or the Aries Model 329 Phase Shifter.
Some of those designs, and the Jet Phaser also have a "bias" trim, kind of directly connected (without opamp) to the LFO output, that also seems to act as sweep adjustement. Do you think this simple design may also be a solution?

Mine does look like moog did , I just kept the idea. Note that moog uses a +V/0/-V control.


actually it's pretty simple. You add a DC voltage with the FLO signal. This DC voltage will move the range of the LFO . I think it plays with the bias point of the op-amp. So you just need an inverting mixer op-amp (or simply a mixer) , one path for the LFO the other for the additonal dc level that can be altered with a pot to give different voltages. At the middle (so v/2) you get the classic phase sound.

I didn't bother myself and didn't put tail resistors but you may consider adding some to make the control more precisely .

you've a good explanation here :
http://techniguitare.com/forum/concepti ... ser%20moog (in french)

it's a commun thing on synth to have VC control . (the all analog synths are based on CV controlled electronics) . So you can connect what you want to control the parameters . (most are based on bipolar power supply , so there's no positive bias to deal with )

Thanks for your explanation!

Indeed, Moog manuals are very instructive.
I've also read the topic on techniguitare and had an interesting conversation with micmicman.

I understand pretty well the concept to had a DC offset to the LFO to move the sweep.
The way I did it didn't really worked: I mixed the LFO output (at pin 7 of U3b) with a DC offset (a pot between V+ and 0V with tail resistors).
It moved the central frequency of the sweep, but the extremes of the sweep (dependant of the LFO depth) didn't moved accordingly, so it only results in a reduction of the sweep.
I assume it didn't worked because I altered the original design before the depth pot and the exponentiated circuit...

I'll carry on with more tests on Switchercad.