I ought to incorporate a diagram but I don’t know how to post images here.
I’m using delayed or fade in vibrato but it’s a problem,
Here’s roughly how I’m doing it.
LFo sine frequency into VCA …then out of VCA into attenuator . Then this goes to 921a or a single oscillator . The VCA is controlled by a 911 and various settings give me the fade in vibrato particulaly the Attack control.
But it’s giving me many problems . The fade in starts okay and the vibrato takes effect but then it tends to grow and go over the top in strength, something to do with the 911 controller. ? I cannot achieve a gentle fade in and fade out or sustain. The 911 controls don’t seem to control the signal properly., VCA is set to Lin.
I routed the LfO signal thru a High Pass filter which helps smooth the LFO but doesn’t solve the problem, I think I’m missing something …maybe in the order I’m patching ?
Any tips would be most welcome
I cannot find much about delayed / fade in vibrato apart from the general description.
I know the Attack on the 911 to LF0-VCA is the dominant control here but how should the D S R controls be set for an average ordinary vibrato ? Are they of any use ?
As in a lot of other cases it is a matter of taste, I’d say. Unfortunately it is omitted often, but omitting it makes a sound artificial and stupid in my opinion, so what you’ve tried is important.
The D S R controls are important as well. Here some sound examples of my Oberheim Sem Clone (yes, I know, what the heck does this do in this forum), where one example does something like a string. In this example I do not fade in the LFO as you do (which makes the sound artificial), but I fade out the vibrato which is a nice add especially in the lower frequency part:
Thanks again C. I guess it’s down to trial and error with the ADSR now but at least the signal is controlled and is much much better .
Nice little video of your Oberheim sounds. Can you tell me what the sound Brass 1 is ? (At about 0.40 ) ? I think it’s two timbres ? …how was it done ?
Your general concept is correct, but on a Moog modular, delayed vibrato requires a 911a dual trigger delay module.
Control Patch:
LFO source to VCA signal in.
VCA signal out to Osc CV in.
EG CV out to Attenuator in.
Attenuator out to VCA CV in.
Instead of triggering the EG directly from the kbd trigger, you route the kbd trig to 911a trig in and then the first delay channel trig out to the EG trig in.
Control settings:
Set VCA to zero (so there is no vibrato until the EG opens it).
The delay setting on the 911a sets how long after the key press the vibrato starts.
The EG attack sets how long it take for the vibrato to reach full strength once the delay time on the 911a is reached.
You set EG sus at 100% if you want the vibrato to remain constant once it reaches peak modulation.
EG release sets how long the vibrato takes to die out after you release the key.
And the attenuator sets how much vibrato you get when the EG is at its sustain level.
The background picture of the video shows the “Brass 2” patch, so you can see the adjustment possibilities in principle there. Similar to “Brass 1”.
“Brass 1” details:
VCO adjustment: A symmetrical mixture between triangle and saw. I added SAW<=>TRIANGLE morphing to my Oberheim VCO clone. The Minimoog does something similar, but not morphable like my VCO, just a fixed mixture. With a Moog Modular you would have to mix a saw and a triangle with e.g. a CP3(A).
Additionally a 75% duty square was added from the VCO. So the sound base is a mixture of three waveforms.
VCF adjustment: The Oberheim State Variable VCF. Sounds more bitchy compared to a Moog ladder. You see the CUTOFF and RESONANCE adjustments in the video. The CUTOFF is modulated by an envelope.
It is patched as NOTCH, which is my favorite filter adjustment. To do this with a Moog Modular you need the 904-A, 904-B and the 904-C (what is my personal favorite filter adjustment in the Moog Modular as well). The Oberheim VCF is morphable between Low Pass <=> NOTCH <=> High Pass, and I weighted Low Pass a bit higher. I don’t know how to do this with a Moog Modular, perhaps by using another CP3(A) and processing the 904-A and B directly?
Many thanx C for detailed explanation and not what I expected . I think it’s the morphing trick that got my ears as I’ve been looking to achieve this a long time.
I’ve tried with EG’s and 911a etc using different adjustments but it never quite works.
It’s that tone where there seems a slight filter opening in it and is very illusive, where you press a key and get this slight shift of tone …. but thanx for describing how to do it on a modular , much appreciated. I’ll be trying this for sure al be it minus Oberheim.
I wonder if there’s any module that enables morphing on a Moog ? Maybe ?
What I consider as confusing for ears (at least for mine) is manipulating CUTOFF in a NOTCH filter topology, as low pass filter and high pass filter react in a kind of opposite way. That is what I did with the “Brass 01” patch. It is difficult to follow the change done by the envelope. Perhaps that is what you describe as “illusive”.
The Oberheim circuits have a lot of morhing capabilities implicitly by providing mixing stages of serveral inputs and outputs “on board” within the modules or functions. Moog modules and module functions are much more “generic”. Providing an “ATTENUATOR” module of its own sais it all.
In theory you can do all that morphing stuff with Moog modules as well. You just need enough generic Moog modules for doing that. But these are “mega-patches” which no one wants to do (beside Wendy Carlos who patched a complete vocoder with Fixed Filters, Envelope Followers, VCAs) and where the most people don’t have that amount of modules.
A former colleague of mine developed an “Interpolating Scanner” for that, where different patches where morphed automatically in sequence. To do this with a Moog modular you need a bunch of VCAs, LFOs, Trigger Delays, Envelopes and a mile of patch cables.
In fact I thought about building additional module cabinets for my System 55 for “generic Moog module banks” to be able to set up those special functions, but I decided to build “de-normalized” Moog modules instead like I did for a customer who wanted a CP3A with VCA capabilities included. That works with the original Moog circuits very good, you just have to do it.
Let’s say I wanted to morph a saw wave into a square wave on every note keyed,
(Not sequencer etc )
The way I do this now is to use two separate patches …saw and square each one OSC -CP3- FILTER -( VCA controlled by 911 with 911a delay)
Only one patch needs this .
By blending these two patches and delaying one I get a sort of a morph sound
Ie the Saw starts the note with filter opening and then split second later the square wave triggers . It’s basic but it gives many varied tones.
I don’t know of any other way for this morph sound bearing in mind it has to be musical and playable in a passage etc.
You mention a dedicate morph module what have you in mind ? Maybe you want to private message me for this ?
I think you still need two envelopes and a gate/trigger delay to perform morphing. And I did not find any hint for DC coupling of the inputs of this module, which you would need for (delayed) amplification of control voltages like LFO signals for vibrato or tremolo.
For a complete morpher you need 2 envelopes, 1 trigger/gate delay, 2 dc coupled VCAs and one dc coupled mixer, I’d say. With that you can cover audio signal and control voltage morphing completely.
Again my offer to provide that morpher with all specified features above as one single monolithic module on interest.
Good point to check whether the Q158 is DC coupled, though I don’t know why you would expect that it isn’t. Even the primitive Moog 902 is DC coupled.
But supposing it is DC capable, it covers the two VCAs plus mixer part of your description of a ‘morpher’. And it also has handy knobs to condition the CV(s) in a complementary way. It can be a cross-fader for audio or CV, which is the basis for a morphing patch, and it simplifies a lot of the patchwork.
As for the controlling CV, two envelopes and a trigger delay are one good method among several others. I wouldn’t see much value in hard wiring those into a module. Often one simple envelope or an LFO could control the cross-fade/morph amount.
'Cause I know more VCA circuits from different brands or DIY which are AC coupled than DC coupled. But I might be wrong in this case.
Yes, and these are good capabilities already.
Sure. It is a more philosophical question, and a question how much do you love patch cables and walls of modules. Do you normalize a modular setup by drilling down everything to generic basic functions or do you combine generic modular functions in modules to de-normalize a modular setup for convenience reasons. I see advantages and disadvantages for both approaches. You can split up a VCO into 3 sub functions (a controller, an exponentiator and an oscillator) for instance (indeed I saw circuits and module concepts which do that) or a vocoder into a bunch of fixed filter banks, envelope follower modules and VCAs (Wendy Carlos did that, AFAIK), but most modules are somehow de-normalized. How much you combine to a real module is somewhere in between.
Sounds like we are mostly in agreement. I think I favor a higher degree of normalization in a modular than most. In this case, I would definitely normalize two envelopes and a trigger delay together. (Actually part of my plan for the MOS-Lab cabinet I recently purchased.) and I like the integration of the mentioned Q158.
Overall, I lean away from putting too much under one front panel, as it often becomes too tempting in larger modules to pack more knobs and jacks into a tighter space. In other words, to put 4MU worth of interface into 3MU space.