Realtime Spice?

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I've noticed that there are some plugins that say they use Spice: Wavearts tubesaturator or DMG tackcomp.
Is there any information, tutorials, tips, etc. on how to start using SPICE in real time with simple things?
Thanks!

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This maybe - http://www.livespice.org/
Apparently a VST version is coming but I think it's said that for about 5 years !

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They may not use Spice, but Newton Raphson, as Spice is using it behind the scenes. You write your equations based on the schema, discretize them and then run NR, and you get Spice (OK, depends which Spice you are talking about!)

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I think people are using Spice in different ways. I think andy-cytomic mentioned using a custom code generator for Spice-like netlists but I think he was using Spice (and hardware) for checking results. I forget who, but somebody else was using Spice to tinker with component models until they emulated hardware.

Mystran was working on something similar tp Livespice in VST form a few years ago but I've not seen it mentioned for a while.

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resynthesis wrote: Mystran was working on something similar tp Livespice in VST form a few years ago but I've not seen it mentioned for a while.
It's on hold until I can find the time to do something about it again.

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:tu:

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mystran wrote:It's on hold until I can find the time to do something about it again.
The spice must flow in real time.
SLH - Yes, I am a woman, deal with it.

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mcbpete wrote:This maybe - http://www.livespice.org/
Apparently a VST version is coming but I think it's said that for about 5 years !
i stopped holding my breath for that one. after getting everyones hopes up like that, he better be dead or got lost or something

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There seems to be source code for this, so I guess it is not impossible to take a stab yourself :)

Looks very interesting for sure.

Richard
Synapse Audio Software - www.synapse-audio.com

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mcbpete wrote:This maybe - http://www.livespice.org/
Apparently a VST version is coming but I think it's said that for about 5 years !
The developer just left the project unfinished. I mailed him some months ago and he told me that he has no more time to invest in the project. It Is on github tho...

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Spice is not designed to run in realtime, and it doesn't match amplitude and/or phase responses near nyquist either. Developers that say the have optimised Spice I doubt very much have gone and edited the Spice source code to make it run faster, otherwise they would be selling their own version of Spice and everyone would buy it since speed matters for everyone, including people designing circuits, and they would pay decent money for something that runs x10,000 faster! What those developers probably mean is they are using the same methods that Spice does, ie Modified Nodal Analysis (MNA) with a root finding algorithm - this is what Cytomic has done since launch around 9 years ago, so welcome to the party!

I use phrases like "uses the same algorithms that circuit simulators use but optimised to run much faster", and don't bother going into too much more detail as the details are quite technical and not suitable for general marketing. I do have a netlist based semi-automated solver, and in my latest plugin The Scream https://cytomic.com/scream you can import spice diode statements via a diodes.lib file, as well as edit the value of every parameter of every component in the circuit. The circuit cannot be changed, only the values of the components, but I have added extra components so you can change the pedal into any of a number of Tube Scream type pedals. This I think is one of the most detailed analog modelling plugin on the planet, and solves 14 stereo pn-junctions in realtime, including op-amp slew rate limiting and output voltage limiting, diode normal and recombination saturation and non-linear capacitances and more. There is a schematic of the circuit that is solved here, but this doesn't include the full boyle op-amp internals but you can edit all their parameters in the plugin: https://cytomic.com/files/TheScream-Schematic.pdf

Getting a fully automated, stable, low cpu generic circuit simulator running as a plugin requires a lot of work. The trouble is that not even Spice is stable all the time, it is very easy to get it screw up and not give a reasonable solution, and it doesn't have any fixed sample rate or low cpu constraints!
The Glue, The Drop, The Scream - www.cytomic.com

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Thanks to all,
So, in the end it is to know how to discretize a circuit,
I would like, at least, to discretize something as simple as a rectifier or something. I do not want the final result, I want to learn how to do it by myself, but I still can not find something basic that I can understand.

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andy-cytomic wrote:This I think is one of the most detailed analog modelling plugin on the planet, and solves 14 stereo pn-junctions in realtime, including op-amp slew rate limiting and output voltage limiting, diode normal and recombination saturation and non-linear capacitances and more.
:clap: Such attention to detail and high skill level.

I'm so lazy, I would be stuck trying to regress the whole thing rather than hand code it. If I can't see the code in my head then I have nothing to write, so I might as well let the computer write a matching function itself. But then again, then I usually have to adjust the objective functions by hand to fine tune. Oh well.

https://en.wikipedia.org/wiki/No_free_l ... timization
SLH - Yes, I am a woman, deal with it.

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There's also Multisim, which I think uses Spice as basis, not free though.

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This I think is one of the most detailed analog modelling plugin on the planet
I guess you're going to make a lot of friends with this sentence from people doing guitar amplifier simulations for a living for more than 9 years :D

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