### The over-whole MT2 tone (and the bass variation)

This entry is part 1 of 13 in the series Analog modelling

In the last blog post, we saw the individual effect of each stage of the Boss MT2 pedal. But with all these effects impacting each other, what is the final find of spectrum that we get?

### The MT2 pedal sections: analysis

This entry is part 2 of 13 in the series Analog modelling

In the previous entry in this series, we saw the effect of the gyrator in a circuit. Now we can analyse each stage individually.

### Analysis of the Boss MT2 Metal Zone pedal (2)

This entry is part 3 of 13 in the series Analog modelling

After a long pause, let’s go on on our MT2 discovery trip. Last time, we analyzed the perfect gyrator that is sometimes used to replace coils.

### How to model an opamp? (the implications on simulation)

This entry is part 4 of 13 in the series Analog modelling

It’s a question I always asked myself. Models in SPICE are usually for full models, or you can use a gain voltage gain as well. What are the implications of selecting one model over another for a real time model? Let’s go for the more complex model to the simplest ones.

### Should I invert my matrix or not?

This entry is part 5 of 13 in the series Analog modelling

In almost all analog modeling algorithms, we solve a (non-)linear system they require at some point to solve $A x=y$, with given $A$ and $y$. Depending on the size of the matrix and its characteristics, computing an inverse can be costly and may incur numerical problems. Let’s tackle cost in this discussion.

### Analysis of the Boss MT2 Metal zone pedal (1)

This entry is part 6 of 13 in the series Analog modelling

I create a model of the Boss SD1 and the Ibanez TS9 some time ago. Now it’s time to get on modelling another pedal, the famous Boss MT2 Metal Zone.

There are many pages online that also analyse this pedal, but I’d like to start from the schema, split in independent pieces and analyze them with my Modelling  Lite tool. The end result will probably end up as a new plugin, but this is currently outside the scope of this new subserie.

### From netlist to code: strategies to implement schematics modelling results

This entry is part 7 of 13 in the series Analog modelling

Last month, I presented my latest work on Audio ToolKit at ADC 2018, namely how I turned a SPICE netlist to a filter.

It is now time to present some of the results here.

### From netlist to code: strategies to implement schematics modelling

This entry is part 8 of 13 in the series Analog modelling

Today, I’m presenting at the ADC my work on analog modelling for the past year.

I will make a more detailed post later this year, but I’d like to put some teasers here. SPICE net lists are an efficient way of representing electronics circuits and there are several very good free and paying simulators. Unfortunately, they are not easy to integrate in a VST plugin.

Audio ToolKit now has a sister project around this topic. The lite version is also licensed under the BSD and can generate a dynamic filter of a net list. The full project is now also capable of generating static filter, with a source file (and compiling it in memory) that can be manually tuned.

Future work on this project will include different solvers for the static filter, as well as a tuner that will be able to drop entries in the Jacobian (full entries or component contributions for a given pin) in the Newton Raphson solver.

### Analog modelling: The Moog ladder filter emulation in Python

This entry is part 9 of 13 in the series Analog modelling

After my previous post on SPICE modelling in Python, I need to use a good support example to go up to on the fly compilation in C++. This schema will also require some changes to support more than simple nodal analysis, so this now becomes Modified Nodal Analysis with state equations.

### Analog modelling: A prototype generic modeller in Python

This entry is part 10 of 13 in the series Analog modelling

A few month ago, mystran published on KVR a small SPICE simulator for real-time processing. I liked the idea, the drawback being that the code is generic and not tailored like a static version of the optimizer. So I wondered if it was doable. But for this, I have to start from the basics and build from there. So let’s go.