Signal path

Micky

Signal path
« on: October 15, 2021, 11:23:36 PM »
Just out of interest,
i found it nowhere... how´s the signalpath of this synth ?
Like Prophet 6 and so on, continuous true analog up to the outs when using no effects ?
Is there a block diagram anywhere ?

All that only for information, no diskussion about the importance of true analog is necessary...

Thank´s for information !

Micky

Re: Signal path
« Reply #1 on: October 17, 2021, 01:27:55 AM »
Just out of interest,
i found it nowhere... how´s the signalpath of this synth ?
Like Prophet 6 and so on, continuous true analog up to the outs when using no effects ?
Is there a block diagram anywhere ?

All that only for information, no diskussion about the importance of true analog is necessary...

Thank´s for information !

Really ? Nowbody know´s ?

Re: Signal path
« Reply #2 on: October 17, 2021, 03:49:57 AM »
Just out of interest,
i found it nowhere... how´s the signalpath of this synth ?
Like Prophet 6 and so on, continuous true analog up to the outs when using no effects ?
Is there a block diagram anywhere ?

All that only for information, no diskussion about the importance of true analog is necessary...

Thank´s for information !

Really ? Nowbody know´s ?
This has been beaten to death on the Gearspace Take 5 thread if you want to read through that.

Micky

Re: Signal path
« Reply #3 on: October 17, 2021, 06:46:16 AM »
Just out of interest,
i found it nowhere... how´s the signalpath of this synth ?
Like Prophet 6 and so on, continuous true analog up to the outs when using no effects ?
Is there a block diagram anywhere ?

All that only for information, no diskussion about the importance of true analog is necessary...

Thank´s for information !

Really ? Nowbody know´s ?
This has been beaten to death on the Gearspace Take 5 thread if you want to read through that.
I don´t want´t to read through all, i don´t even wan´t to read anything at gearspace.
So this simple question is to difficult for this official sequential forum ???

LPF83

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Re: Signal path
« Reply #4 on: October 17, 2021, 06:47:09 AM »
Just out of interest,
i found it nowhere... how´s the signalpath of this synth ?
Like Prophet 6 and so on, continuous true analog up to the outs when using no effects ?
Is there a block diagram anywhere ?

All that only for information, no diskussion about the importance of true analog is necessary...

Thank´s for information !

Really ? Nowbody know´s ?
This has been beaten to death on the Gearspace Take 5 thread if you want to read through that.

I'd also be interested in a block diagram, or summary of the design here, if any one has it, as well.  It's the fact that things get beaten to death at GS over the course of pages..upon..pages of responses, many of which are distracting "forum warrior" type responses, that is the reason I don't post there, and why I'd rather get the information in concise format here if possible.
Prophet 10, Prophet 6, OB-6, Prophet 12m, Prophet Rev2-16, Toraiz AS-1, Pro 2, Virus TI2, Moog SlimPhatty, Hydrasynth desktop, Korg Minilogue XDm, Roland JP-8080, Roland System-8, Roland SPD-SX SE / Octapad, Maschine, Cubase

Re: Signal path
« Reply #5 on: October 17, 2021, 02:58:59 PM »
From what I recall, it’s digital after the filters as the amplifier stages are digital.

Re: Signal path
« Reply #6 on: June 20, 2022, 12:22:40 PM »
I too would like a definitive answer on this from a sequential employee.

kpatz

Re: Signal path
« Reply #7 on: June 20, 2022, 03:39:02 PM »
I don't know how often Sequential employees check the forum for questions, but what I know (or think I know, mostly from the Gearspace thread) is: the output of oscillator 2 as well as the output of the filter for each voice are digitized and sent to the DSP.  The amp stage, panning, mixing of the 5 voices, overdrive, effects and master volume are all digital.

The SSI2130 VCO chips each have a 5-VCA mixer on board.  These are used in the Take 5 to mix the sine, saw and pulse waveforms (controlled by the shape knobs) as well as noise and sub osc level and also to control oscillator mix in the mixer section.  These mixes are sent to each voice's SSI2140 VCF, and also the waveform blend of osc 2 is sent to an ADC channel for use in 2->1 FM and the mod matrix.  When 2->1 FM is off, osc 2's mix level controls the VCA CVs for that oscillator's waveforms which also hit the ADC, which is why with FM off the mix level affects the amount of modulation you get in the matrix from Osc 2.  When FM is on, Osc 2's VCA output is automatically maxed out when sent to the DSP (but muted going to the VCF), and the FM depth is controlled in the DSP, which mixes the Osc 2 signal into the Osc 1's digitally-generated pitch CV.

I don't know how the white and pink noise are implemented but I'm thinking they're created digitally in the DSP and fed to a DAC channel that is fed into the filters mixed with the VCO waveforms.  I don't know if one of the SSI2130 on-board VCAs is used for noise level or if that's handled digitally.  Noise is a mod source so it's in the DSP one way or the other, whether digitized analog noise or generated digitally.

TL;DR: VCOs, sub osc, waveform blend and oscillator mix, and VCFs are analog, everything afterward is digital.  Mod matrix is digital including 2>1 FM.  White/pink noise is likely digital.

Re: Signal path
« Reply #8 on: June 21, 2022, 10:21:09 AM »
This is pretty much what I gathered but thank you for condensing it down to one spot. Pym and cmbd work for sequential and I see them on the forums so that’s why I was hoping for them to see this. I think the take 5 sounds great either way but I feel like a lot of people want this question directly answered.

Re: Signal path
« Reply #9 on: June 21, 2022, 03:30:33 PM »
I would also love to see a block diagram of this synth; It would help explain _why_ this synth is so powerful.

Sadly, the marketing page for the Take 5 still doesn't mention any details about the modulation matrix.

- 16x mod routes + dedicated LFO1, LFO2, and AuxEnv routes
- 4x audio rate modulation sources (Osc2, Noise, Filter Out, and Audio Out)
- Random modulation source separate from Noise
- Voice Spread, Note Number, and and DC modulation sources
- 1x Overdrive mod destination, 3x FX mod destinations, and 4x Reverb mod destinations
- Ability to "stack" multiple modulation routes to "overdrive" certain modulation destinations into wild audio territories (i.e. FM amount, Filter Drive, Osc1Octv)

All that is made possible, in part, because of the signal path. The circuit layout would be a lot more complex otherwise.

Honestly, after reverse engineering some of the signal path on my personal Take 5, the architecture really is an elegant blend of analog and digital technology.

Just like the Prophet 5 was the "no-nonsense" approach to building a digitally controlled analog polysynth in it's day, the Take 5 feels like the "no-nonsense" approach to building a digitally controlled analog polysynth today.
« Last Edit: June 21, 2022, 03:36:33 PM by jamisnemo »

Re: Signal path
« Reply #10 on: June 26, 2022, 04:51:39 PM »
Any moderators or design team willing to chime in?

Re: Signal path
« Reply #11 on: June 30, 2022, 08:48:55 PM »
For anyone interested I did get a straight forward answer on this which goes as follows.

Thanks for reaching out. Happy to help with your Take 5 inquiry.
 
It's good to note that the Take 5 uses a novel approach to the individual synth voices. In each voice, two fully analog VCOs are mixed (with noise) into a fully analog VCF. At this point, rather than adding a VCA, we simply digitize the voice at the filter output. While this is somewhat different than normal, it enables us to have transparent virtual VCAs, without adding noise, distortion, control-voltage feedthrough and other unwanted artifacts.
 
Traditionally, many analog synths get a lot of their personality from all kinds of wanted and unwanted artifacts. This is true in the Take 5 also! The analog filters and VCOs are where all the action takes place. As we found, the VCA contributes but a tiny fraction of analog flavor to a synthesizer, so when you play the Take 5 you will be hearing nothing but the best analog goodness from the VCOs and VCFs.
 
I hope this helps.
Best,
Brian
Sequential | Oberheim

Re: Signal path
« Reply #12 on: July 11, 2022, 12:48:20 AM »
Awesome! Thank you for sharing!

So, if I'm understanding correctly, each voice probably looks something like this?
Code: [Select]
From mod matrix -> DAC -> Analog VCO1  \
                -> DAC -> Analog VCO2  --> VCF -> ADC into DSP -> Digital VCA's for Pan and Main mix -> ADC -> Main output
                -> DAC ->  (??) Noise  /                       -> To Mod Matrix as VCF output source -> To Mod Matrix as audio output source

That doesn't include mixing into the VCF (where Filter Drive is managed) which is probably done in the analog domain. So for those levels to be mod matrix destinations means a pile of additional DAC's out of the DSP just for mixer levels.

And the VCF cutoff, and resonance are also mod destinations so that's more DAC's back into the analog domain (per voice)...

And that doesn't include an ADC to get VCO2 into the mod matrix as a source.

And that also doesn't include the FX sections or Overdrive. FX is obviously in one of the SHARC cores. Is Overdrive analog on this thing?

Man, there is SO much mixed domain circuitry in the Take 5. And it sounds damn good.
« Last Edit: July 11, 2022, 12:50:41 AM by jamisnemo »

Re: Signal path
« Reply #13 on: August 02, 2022, 06:07:02 PM »
I think the overdrive is analog, but no way to confirm. It IS in the Pro 3 AFAIK.