SSF zero point oscilator

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Post by johannes » Fri Dec 20, 2019 3:26 am

comacomfort
looking forward to hear that!


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Re: SSF zero point oscilator

Post by matttech » Tue Dec 24, 2019 9:09 am

That video has some damn fine sounds in it. Good effort! :tu:

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Post by BasariStudios » Mon Dec 30, 2019 11:30 am

johannes wrote:
Mon Dec 16, 2019 2:10 pm
has anyone here expericence with both – the rubi and the zpo – and can elaborate on fm possibities that both offer and how they differ?
thanks for any insights. peace
Lol:

I also find the Rubicon more Clinique.
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Re: SSF zero point oscilator

Post by BasariStudios » Mon Dec 30, 2019 11:39 am

NoLegs wrote:
Mon Dec 23, 2019 5:32 pm

I just wanna point out there is few wrong things in this video, which can be misleading
and i know Ben missed it, not on purpose. This VCO you can clearly see is out of Calibration,
completely, secondly when scanning wave outputs the waves are clean but he probably
forgot the ZP half way in and thirdly, the SAW on the ZPO is clean, there is no Kink to it,
if you go straight to 13.42 here where the SAW has one cut in it it is due to Modulation being
plugged into ZP Control, if you unplug it it is a clean saw without the Cut in it:



When you plug something into ZP Control it usually affects the SAW and other Waves
without any attenuator being up, that is why the saw has a Kink to it.
Last edited by BasariStudios on Mon Dec 30, 2019 11:56 am, edited 1 time in total.
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Re: SSF zero point oscilator

Post by BasariStudios » Mon Dec 30, 2019 11:51 am

And if you look here at 06.45, the Waves are totally out of place and asymmetrical,
it clearly needs Calibration, the Waves on mine are nothing like this:


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Re: SSF zero point oscilator

Post by LunaticSound » Wed Jan 01, 2020 2:12 pm

Is there any hope for a proper manual for the ZPO?

I would really really like to understand the Zero Point better, how it interacts with FM, what it does without FM being present and it's influence on the PWM for example.

Sometimes I don't really get it...

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Re: SSF zero point oscilator

Post by analogPedagog » Wed Jan 01, 2020 3:15 pm

LunaticSound wrote:
Wed Jan 01, 2020 2:12 pm
Is there any hope for a proper manual for the ZPO?

I would really really like to understand the Zero Point better, how it interacts with FM, what it does without FM being present and it's influence on the PWM for example.

Sometimes I don't really get it...
Yes, the manual will be available soon. Can help you with your questions for now.

How it (Zero Point) interacts with FM:

It doesn't, they are completely separated circuitry.
The only connection between them is that a signal patched into LIN FM or EXP FM when either or both FM inputs are TZ-MOD enabled, will route to the Zero Point control as well. But the two have no affect on one another.

what ZP does without FM being present:

Let's start with assuming you have no modulation patched into the ZPO.

In that case, the Zero Point control acts as a TZVCA with some differences.
As being part of the triangle core, the output is fed into all the wave shaping circuitry and will modify the waveforms that are dependent on the Triangle for their respective shape transformations.
So when the Triangle's amplitude is altered via the ZP control, so are the shapes and amplitudes of all the other waveform outputs.
The default state for ZP, without modulation applied would be fully CW or CCW depending on if you want a normal or inverted output - as it is a TZVCA.
But that doesn't mean you cannot utilize zero point for additional wave shaping and VCA effects either by hand or with a slower mod source.
An audio rate mod source into ZP produces purely Ring Modulation, no FM.

ZP's influence on the PWM for example:

So as far as the PWM is concerned, the Triangle determines the duty cycle of the Pulse, so if the Triangle amplitude changes via the ZP control, this will also affect PWM slightly when you alter the ZP position. Any major change only occurs within the 11:30 to 12:30 region as this is where the greatest amplitude change occurs. ZP is a TZVCA but it is not by any means linear, it is designed to switch very quickly at audio rates while ensuring a smoother transition In direction.

So to be clear about the PWM and ZP specifically and assuming your have PULSE WIDTH set to 50% duty - There will be a dramatic and non linear change in PW as the ZP control is swept between the narrow region at the apex of the ZP control - being a 0% duty cycle when ZP is in absolute center, flipping negative to the left and positive to the right. This has consequences depending on how you use it in this manner.

When audio rate modulation is used through ZP CV - whether on its own or via TZFM mode, the ZP PWM effect and the main PWM control/CV double down on one another - effectively causing multiple pulses to appear on the pulse output - both effected by changes in PWM and ZP.

You are definitely helping me with some good things to add to manual - this type of Q&A is really helpful for everyone.

-A

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Re: SSF zero point oscilator

Post by LunaticSound » Wed Jan 01, 2020 7:20 pm

Aaaaahhhh! Wow.

And since you approved of my questions, here I go:

When the TZFM input is set to ALL, does that mean, that the incoming signals on those Jack's are both sent to the TZVCA? So can there be Lin and Log TZFM at the same time? :eek:

If I offset the Zero Point all the way to -, does that mean, any incoming modulator will perform normal AM on the waveform?
On your website, it is worded the way, that the Zero Point also acts as an Index VCA, is that by setting it all the way to + and then sending a negative envelope to the Zero Point?
These two questions go somewhat together, if the answer is no, then I didn't get it completely :lol:

I love it, how the Zero Point allows for some extra control over the shapers, it's really clever and sounds great. Really impressive, man. The double influence on the PulseWidth, which results in the Pulse sometimes disappearing over wider regions of the knob, was what was making me feel, I am missing something, though, so this piece is important to know, I guess.

Oh, and one last question, if you don't mind:
How do the standard Lin and Log FM modes deal with modulators pushing the freq below 0? Or is the modulator always rectified?

Thanks a lot, I am absolutely loving this!

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Re: SSF zero point oscilator

Post by analogPedagog » Thu Jan 02, 2020 7:39 am

LunaticSound wrote:
Wed Jan 01, 2020 7:20 pm
Aaaaahhhh! Wow.

And since you approved of my questions, here I go:

When the TZFM input is set to ALL, does that mean, that the incoming signals on those Jack's are both sent to the TZVCA? So can there be Lin and Log TZFM at the same time? :eek:

If I offset the Zero Point all the way to -, does that mean, any incoming modulator will perform normal AM on the waveform?
On your website, it is worded the way, that the Zero Point also acts as an Index VCA, is that by setting it all the way to + and then sending a negative envelope to the Zero Point?
These two questions go somewhat together, if the answer is no, then I didn't get it completely :lol:

I love it, how the Zero Point allows for some extra control over the shapers, it's really clever and sounds great. Really impressive, man. The double influence on the PulseWidth, which results in the Pulse sometimes disappearing over wider regions of the knob, was what was making me feel, I am missing something, though, so this piece is important to know, I guess.

Oh, and one last question, if you don't mind:
How do the standard Lin and Log FM modes deal with modulators pushing the freq below 0? Or is the modulator always rectified?

Thanks a lot, I am absolutely loving this!
When TZ-MOD switch is set to all:

Yes, both LIN and EXP is performing TZFM at the same time. You will have two FM operators and potentially 3 TZAM operators (if a 3rd signal is patched into Zero point) going on at the same time.

To be clear, you will have a rectified Linear FM and rectified Exponential FM feeding the VCO core. As well as un-rectified copies of those mod sources summing together into the Zero Point circuitry. And then, you can add a third mod source into the ZP CV input for a total of 3 summed signals into Zero point.


ZP index and impact on a ZP modulation:


ZP is an index control, yes so essentially behaves as an offset to any incoming ZP CV signal. You are correct that if you set ZP to negative or positive, you are offsetting the signal that is reversing the VCO waveform in that direction. So for example, if you set ZP to negative and apply a positive envelope, that envelope is going to sweep the ZP modulation from the set region all the way up to zero (ie centered at 0V), depending on the level of the envelope and finer position of the ZP control. Same goes for ZP being in the positive region and applying a negative envelope. This is the basis for performing dynamics related but not limited to more clangorous and bell-like tones.

follow up on the double influence on PW via PWM and ZP:

The case where pulses disappear has to do with the actual PW control being set to the extremes where the pulse width is very thin. Due to the PW crossover effect of ZP, pulses may become thin enough to disappear - so it is important to know that so you can properly govern that effect.

How do the standard Lin and Log FM modes deal with modulators pushing the freq below 0? Or is the modulator always rectified?:

TZ-MOD switch determines whether a particular FM CV input is rectified or unaffected by the CV rectifier. As long as an FM input is not selected to perform TZFM, the signal will not be rectified (ie standard FM is not rectified). So standard FM will push the frequency low when going down through 0V. This is interesting because you can perform what I am calling hybrid FM/TZAM, an effect where you can perform standard FM while also reversing the waveform direction with the same or separate modulation source patched into Zero Point.

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Re: SSF zero point oscilator

Post by LunaticSound » Thu Jan 02, 2020 10:07 am

Holy cow. There is a lot more going on than I thought.

So it is basically possible to have non rectified FM (not thru zero) , rectified FM with wave reversal by the VCA (Thru Zero) , non rectified FM with Wave reversal (which is... just rectified, upwards FM? :hmm:) and then all of this linearly and exponentially...

Time to do some experiments, I guess. :party:

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Re: SSF zero point oscilator

Post by BasariStudios » Thu Jan 02, 2020 7:56 pm

LunaticSound wrote:
Thu Jan 02, 2020 10:07 am
So it is basically possible to have non rectified FM (not thru zero) , rectified FM with wave reversal by the VCA (Thru Zero) , non rectified FM with Wave reversal (which is... just rectified, upwards FM? :hmm:) and then all of this linearly and exponentially...
Exactly that and some more. In my ZPO Videos i got tired
Just naming the Combinations you can do, lol.

TZ XP STD Lin
TZ Lin STD XP
STD Lin STD XP
TZ Lin TZ XP

STD (Standard FM)

Now add to it the Rectifier or no Rectifier.
Amplitude Modulation.
Ring Modulation.

...and to all of the above Combos Sync on top.

I just finished a Rubicon 2 VS ZPO video and while doing it
I learnt more and discovered more things on the ZPO.
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Re: SSF zero point oscilator

Post by ari ellis » Fri Jan 03, 2020 10:53 am

I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal, (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?

Maybe I'm being overly academic; when using e.g. a rubicon with the symmetry control locked (or otherwise near-zero), the excursion from the carrier frequency down to zero happens pretty fast... I wonder how audible the difference is? Looking forward to BasariStudios's video!

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Re: SSF zero point oscilator

Post by analogPedagog » Fri Jan 03, 2020 11:17 am

ari ellis wrote:
Fri Jan 03, 2020 10:53 am
I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?
First off, never claimed that the instantaneous frequency goes to or through zero.

Also, If you think this is not how analog TZ modulation is achieved (using a rectifier), I urge you to read up on how some of the synth greats accomplished TZFM in periodicals such as Electronotes. I guess they had it wrong too?

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Re: SSF zero point oscilator

Post by ari ellis » Fri Jan 03, 2020 11:29 am

analogPedagog wrote:
Fri Jan 03, 2020 11:17 am
ari ellis wrote:
Fri Jan 03, 2020 10:53 am
I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?
First off, never claimed that the instantaneous frequency goes to or through zero.

Also, If you think this is not how analog TZ modulation is achieved (using a rectifier), I urge you to read up on how some of the synth greats accomplished TZFM in periodicals such as Electronotes. I guess they had it wrong too?
You've generously and clearly explained the operation, so fair enough. Though you do call it TZFM; I think that sort of implies the frequency goes through zero. But I have to admit I'm not sure of a clearer, still-compact way of naming what your device does, so I shouldn't complain too much.

And I'm not saying there is no need for a rectifier in achieving TZFM. Just that TZFM is somewhat different from simply rectifying the modulator, flipping phase, and calling it a day. This is mathematically obvious IMO.

EDIT: I've re-read the SSF website, and to be fair to analogPedagog, he never actually claims that the ZPO is capable of "normal" TZFM. I misremembered the labelling of TZ-MOD.
Last edited by ari ellis on Fri Jan 03, 2020 11:43 am, edited 2 times in total.

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Re: SSF zero point oscilator

Post by analogPedagog » Fri Jan 03, 2020 11:39 am

ari ellis wrote:
Fri Jan 03, 2020 11:29 am
analogPedagog wrote:
Fri Jan 03, 2020 11:17 am
ari ellis wrote:
Fri Jan 03, 2020 10:53 am
I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?
First off, never claimed that the instantaneous frequency goes to or through zero.

Also, If you think this is not how analog TZ modulation is achieved (using a rectifier), I urge you to read up on how some of the synth greats accomplished TZFM in periodicals such as Electronotes. I guess they had it wrong too?
You've generously and clearly explained the operation, so fair enough. Though you do call it TZFM; I think that sort of implies the frequency goes through zero. But I have to admit I'm not sure of a clearer, still-compact way of naming what your device does, so I shouldn't complain too much.

And I'm not saying there is no need for a rectifier in achieving TZFM. Just that TZFM is somewhat different from simply rectifying the modulator, flipping phase, and calling it a day. This is mathematically obvious IMO.
Thank you for the appreciation.

I am really just pointing out that in respect of how “perfect” TZFM can be achieved digitally, rectifying the modulator, reversing the direction of the VCO and calling it a day, was and is how it can done in the analog domain.

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Re: SSF zero point oscilator

Post by ari ellis » Fri Jan 03, 2020 11:47 am

analogPedagog wrote:
Fri Jan 03, 2020 11:39 am
ari ellis wrote:
Fri Jan 03, 2020 11:29 am
analogPedagog wrote:
Fri Jan 03, 2020 11:17 am
ari ellis wrote:
Fri Jan 03, 2020 10:53 am
I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?
First off, never claimed that the instantaneous frequency goes to or through zero.

Also, If you think this is not how analog TZ modulation is achieved (using a rectifier), I urge you to read up on how some of the synth greats accomplished TZFM in periodicals such as Electronotes. I guess they had it wrong too?
You've generously and clearly explained the operation, so fair enough. Though you do call it TZFM; I think that sort of implies the frequency goes through zero. But I have to admit I'm not sure of a clearer, still-compact way of naming what your device does, so I shouldn't complain too much.

And I'm not saying there is no need for a rectifier in achieving TZFM. Just that TZFM is somewhat different from simply rectifying the modulator, flipping phase, and calling it a day. This is mathematically obvious IMO.
Thank you for the appreciation.

I am really just pointing out that in respect of how “perfect” TZFM can be achieved digitally, rectifying the modulator, reversing the direction of the VCO and calling it a day, was and is how it can done in the analog domain.
I think I'm just working with a different definition; my introduction to analog TZFM was the rubicon, which is admittedly not the beginning of the story. To me, "perfect" TZFM means implementation of a function like cos((carrier freq + modulation input) * time), and that this function is still realized when the modulation input is negative and larger than the carrier frequency. But I am not well-read enough on the engineering history to know if this is what everyone means; I'm ready to believe you that it isn't.

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Re: SSF zero point oscilator

Post by analogPedagog » Fri Jan 03, 2020 12:03 pm

ari ellis wrote:
Fri Jan 03, 2020 11:47 am
analogPedagog wrote:
Fri Jan 03, 2020 11:39 am
ari ellis wrote:
Fri Jan 03, 2020 11:29 am
analogPedagog wrote:
Fri Jan 03, 2020 11:17 am
ari ellis wrote:
Fri Jan 03, 2020 10:53 am
I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?
First off, never claimed that the instantaneous frequency goes to or through zero.

Also, If you think this is not how analog TZ modulation is achieved (using a rectifier), I urge you to read up on how some of the synth greats accomplished TZFM in periodicals such as Electronotes. I guess they had it wrong too?
You've generously and clearly explained the operation, so fair enough. Though you do call it TZFM; I think that sort of implies the frequency goes through zero. But I have to admit I'm not sure of a clearer, still-compact way of naming what your device does, so I shouldn't complain too much.

And I'm not saying there is no need for a rectifier in achieving TZFM. Just that TZFM is somewhat different from simply rectifying the modulator, flipping phase, and calling it a day. This is mathematically obvious IMO.
Thank you for the appreciation.

I am really just pointing out that in respect of how “perfect” TZFM can be achieved digitally, rectifying the modulator, reversing the direction of the VCO and calling it a day, was and is how it can done in the analog domain.
I think I'm just working with a different definition; my introduction to analog TZFM was the rubicon, which is admittedly not the beginning of the story. To me, "perfect" TZFM means implementation of a function like cos((carrier freq + modulation input) * time), and that this function is still realized when the modulation input is negative and larger than the carrier frequency. But I am not well-read enough on the engineering history to know if this is what everyone means; I'm ready to believe you that it isn't.
Yes, there are a number techniques, some newer than others that may approach that "perfect" idea of TZFM.

I can say from my development that I tried all of them and I found that this scheme I came up with is the one that offered the greatest sonic variety, even if it doesn't 100% meet the accepted mathematical definition of perfect TZFM. The difference in sound was almost indistinguishable and I care more about what I can offer to my users than gaining the respect in satisfying the purists. 99% of music makers could care less about that.

You can make the argument that once you offset the ZP, you are not really doing TZFM either. But that matters little to me since the point is to deviate from the norm, if it has much more sonic variance and playability to offer. At least that is a big part of my design philosophy.

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Re: SSF zero point oscilator

Post by ari ellis » Fri Jan 03, 2020 12:15 pm

analogPedagog wrote:
Fri Jan 03, 2020 12:03 pm
ari ellis wrote:
Fri Jan 03, 2020 11:47 am
analogPedagog wrote:
Fri Jan 03, 2020 11:39 am
ari ellis wrote:
Fri Jan 03, 2020 11:29 am
analogPedagog wrote:
Fri Jan 03, 2020 11:17 am
ari ellis wrote:
Fri Jan 03, 2020 10:53 am
I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?
First off, never claimed that the instantaneous frequency goes to or through zero.

Also, If you think this is not how analog TZ modulation is achieved (using a rectifier), I urge you to read up on how some of the synth greats accomplished TZFM in periodicals such as Electronotes. I guess they had it wrong too?
You've generously and clearly explained the operation, so fair enough. Though you do call it TZFM; I think that sort of implies the frequency goes through zero. But I have to admit I'm not sure of a clearer, still-compact way of naming what your device does, so I shouldn't complain too much.

And I'm not saying there is no need for a rectifier in achieving TZFM. Just that TZFM is somewhat different from simply rectifying the modulator, flipping phase, and calling it a day. This is mathematically obvious IMO.
Thank you for the appreciation.

I am really just pointing out that in respect of how “perfect” TZFM can be achieved digitally, rectifying the modulator, reversing the direction of the VCO and calling it a day, was and is how it can done in the analog domain.
I think I'm just working with a different definition; my introduction to analog TZFM was the rubicon, which is admittedly not the beginning of the story. To me, "perfect" TZFM means implementation of a function like cos((carrier freq + modulation input) * time), and that this function is still realized when the modulation input is negative and larger than the carrier frequency. But I am not well-read enough on the engineering history to know if this is what everyone means; I'm ready to believe you that it isn't.
Yes, there are a number techniques, some newer than others that may approach that "perfect" idea of TZFM.

I can say from my development that I tried all of them and I found that this scheme I came up with is the one that offered the greatest sonic variety, even if it doesn't 100% meet the accepted mathematical definition of perfect TZFM. The difference in sound was almost indistinguishable and I care more about what I can offer to my users than gaining the respect in satisfying the purists. 99% of music makers could care less about that.

You can make the argument that once you offset the ZP, you are not really doing TZFM either. But that matters little to me since the point is to deviate from the norm, if it has much more sonic variance and playability to offer. At least that is a big part of my design philosophy.
Oh, please don't construe what I'm saying as a complaint about the ZPO; my day job is in research science, so I can be quite pedantic about terminology. The world has plenty of "classical" TZFM oscs. I would way rather have more designers like you, pursuing new takes on the core ideas of synthesis.

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analogPedagog
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Re: SSF zero point oscilator

Post by analogPedagog » Fri Jan 03, 2020 12:26 pm

ari ellis wrote:
Fri Jan 03, 2020 12:15 pm
analogPedagog wrote:
Fri Jan 03, 2020 12:03 pm
ari ellis wrote:
Fri Jan 03, 2020 11:47 am
analogPedagog wrote:
Fri Jan 03, 2020 11:39 am
ari ellis wrote:
Fri Jan 03, 2020 11:29 am
analogPedagog wrote:
Fri Jan 03, 2020 11:17 am
ari ellis wrote:
Fri Jan 03, 2020 10:53 am
I've been confused by a lot of this discussion, and am hoping someone here could clear this up for me. It seems to me like the ZPO does a lot of *very* cool things, but none of them are equivalent to actual through-zero FM.

In through-zero FM, the entire point is that when the modulator signal is sufficiently negative as to push the frequency below zero, the polarity reverses and the frequency goes back up. This is totally different from simply rectifying the modulator signal and reversing polarity on half of the cycle. For instance, when full-wave rectifying a modulator signal (the absolute value of) the instantaneous frequency is never smaller than it is with zero modulation. The instantaneous frequency never even goes *towards* zero, let alone through it!

It is a very cool idea to have user-selected rectified or non-rectified traditional FM available simultaneously with a ring modulator. But I think it's inaccurate, and perhaps misleading, to call this through-zero FM (though I'm willing to believe some similar sounds are achievable). Am I missing something?
First off, never claimed that the instantaneous frequency goes to or through zero.

Also, If you think this is not how analog TZ modulation is achieved (using a rectifier), I urge you to read up on how some of the synth greats accomplished TZFM in periodicals such as Electronotes. I guess they had it wrong too?
You've generously and clearly explained the operation, so fair enough. Though you do call it TZFM; I think that sort of implies the frequency goes through zero. But I have to admit I'm not sure of a clearer, still-compact way of naming what your device does, so I shouldn't complain too much.

And I'm not saying there is no need for a rectifier in achieving TZFM. Just that TZFM is somewhat different from simply rectifying the modulator, flipping phase, and calling it a day. This is mathematically obvious IMO.
Thank you for the appreciation.

I am really just pointing out that in respect of how “perfect” TZFM can be achieved digitally, rectifying the modulator, reversing the direction of the VCO and calling it a day, was and is how it can done in the analog domain.
I think I'm just working with a different definition; my introduction to analog TZFM was the rubicon, which is admittedly not the beginning of the story. To me, "perfect" TZFM means implementation of a function like cos((carrier freq + modulation input) * time), and that this function is still realized when the modulation input is negative and larger than the carrier frequency. But I am not well-read enough on the engineering history to know if this is what everyone means; I'm ready to believe you that it isn't.
Yes, there are a number techniques, some newer than others that may approach that "perfect" idea of TZFM.

I can say from my development that I tried all of them and I found that this scheme I came up with is the one that offered the greatest sonic variety, even if it doesn't 100% meet the accepted mathematical definition of perfect TZFM. The difference in sound was almost indistinguishable and I care more about what I can offer to my users than gaining the respect in satisfying the purists. 99% of music makers could care less about that.

You can make the argument that once you offset the ZP, you are not really doing TZFM either. But that matters little to me since the point is to deviate from the norm, if it has much more sonic variance and playability to offer. At least that is a big part of my design philosophy.
Oh, please don't construe what I'm saying as a complaint about the ZPO; my day job is in research science, so I can be quite pedantic about terminology. The world has plenty of "classical" TZFM oscs. I would way rather have more designers like you, pursuing new takes on the core ideas of synthesis.
No, not in the least.
I apologize if I initially came off abruptly. There have been a few who have attacked this concept, and perhaps I was slightly on the defensive.
I think your questions are very important and enjoy the opportunity to express the design more clearly.

ari ellis
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Location: montreal

Re: SSF zero point oscilator

Post by ari ellis » Fri Jan 03, 2020 12:47 pm

analogPedagog wrote:
Fri Jan 03, 2020 12:26 pm
...

No, not in the least.
I apologize if I initially came off abruptly. There have been a few who have attacked this concept, and perhaps I was slightly on the defensive.
I think your questions are very important and enjoy the opportunity to express the design more clearly.
No worries at all! I imagine these threads can get a bit stress-inducing for designers, especially when you're introducing new concepts that have a ring of the familiar. Please keep doing what you're doing, and don't let the purists (or the pedants like me) slow you down. :guinness:

(Sidenote: any chance you'll be adding to your list of Canadian dealers? I'd love to be able to check your stuff out in-store in Montreal)

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Re: SSF zero point oscilator

Post by comacomfort » Fri Jan 03, 2020 1:00 pm

ari ellis wrote:
Fri Jan 03, 2020 12:47 pm
analogPedagog wrote:
Fri Jan 03, 2020 12:26 pm
...

No, not in the least.
I apologize if I initially came off abruptly. There have been a few who have attacked this concept, and perhaps I was slightly on the defensive.
I think your questions are very important and enjoy the opportunity to express the design more clearly.
No worries at all! I imagine these threads can get a bit stress-inducing for designers, especially when you're introducing new concepts that have a ring of the familiar. Please keep doing what you're doing, and don't let the purists (or the pedants like me) slow you down. :guinness:

(Sidenote: any chance you'll be adding to your list of Canadian dealers? I'd love to be able to check your stuff out in-store in Montreal)
Nightlife electronics is based in Vancouver and has online sales, carries the new SSF stuff, i picked up the ZPO there, obviously, not in montreal, but they fly under the radar as a good canadian dealer.

ari ellis
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Posts: 64
Joined: Tue Oct 01, 2019 8:05 am
Location: montreal

Re: SSF zero point oscilator

Post by ari ellis » Fri Jan 03, 2020 1:05 pm

comacomfort wrote:
Fri Jan 03, 2020 1:00 pm
...

Nightlife electronics is based in Vancouver and has online sales, carries the new SSF stuff, i picked up the ZPO there, obviously, not in montreal, but they fly under the radar as a good canadian dealer.
Yeah I saw them, and they'll be my go-to if I order! But I really like getting my hands on things before taking the plunge. No matter how many demos I watch/listen to, I tend to feel like I only really know for sure whether I will make use of something or not once I've had it in front of me.

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Re: SSF zero point oscilator

Post by analogPedagog » Fri Jan 03, 2020 1:16 pm

comacomfort wrote:
Fri Jan 03, 2020 1:00 pm
ari ellis wrote:
Fri Jan 03, 2020 12:47 pm
analogPedagog wrote:
Fri Jan 03, 2020 12:26 pm
...

No, not in the least.
I apologize if I initially came off abruptly. There have been a few who have attacked this concept, and perhaps I was slightly on the defensive.
I think your questions are very important and enjoy the opportunity to express the design more clearly.
No worries at all! I imagine these threads can get a bit stress-inducing for designers, especially when you're introducing new concepts that have a ring of the familiar. Please keep doing what you're doing, and don't let the purists (or the pedants like me) slow you down. :guinness:

(Sidenote: any chance you'll be adding to your list of Canadian dealers? I'd love to be able to check your stuff out in-store in Montreal)
Nightlife electronics is based in Vancouver and has online sales, carries the new SSF stuff, i picked up the ZPO there, obviously, not in montreal, but they fly under the radar as a good canadian dealer.

I would love to have more Canadian dealers. There have been some employees over at Moog Audio that really enjoyed SSF modules, but nothing ever took off as far as establishing them as a dealer. But yes, so far it is just Nightlife Electronics.

ari ellis
Common Wiggler
Posts: 64
Joined: Tue Oct 01, 2019 8:05 am
Location: montreal

Re: SSF zero point oscilator

Post by ari ellis » Fri Jan 03, 2020 1:35 pm

analogPedagog wrote:
Fri Jan 03, 2020 1:16 pm
comacomfort wrote:
Fri Jan 03, 2020 1:00 pm
ari ellis wrote:
Fri Jan 03, 2020 12:47 pm
analogPedagog wrote:
Fri Jan 03, 2020 12:26 pm
...

No, not in the least.
I apologize if I initially came off abruptly. There have been a few who have attacked this concept, and perhaps I was slightly on the defensive.
I think your questions are very important and enjoy the opportunity to express the design more clearly.
No worries at all! I imagine these threads can get a bit stress-inducing for designers, especially when you're introducing new concepts that have a ring of the familiar. Please keep doing what you're doing, and don't let the purists (or the pedants like me) slow you down. :guinness:

(Sidenote: any chance you'll be adding to your list of Canadian dealers? I'd love to be able to check your stuff out in-store in Montreal)
Nightlife electronics is based in Vancouver and has online sales, carries the new SSF stuff, i picked up the ZPO there, obviously, not in montreal, but they fly under the radar as a good canadian dealer.

I would love to have more Canadian dealers. There have been some employees over at Moog Audio that really enjoyed SSF modules, but nothing ever took off as far as establishing them as a dealer. But yes, so far it is just Nightlife Electronics.
Noted! I'll have to pester them about this; maybe if enough of us ask they'll get on board...

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