Log

Calculates the base-2, natural, or base-10 logarithm of a positive input.

What it does #

Log is the inverse of Exp on its valid domain. The Base setting selects log2(x), ln(x), or log10(x), converting multiplicative ratios into additive values.

Controls and ports #

The wrapper exposes one signal input, one signal output, and a Base selector. Base chooses logarithm base 2, e for the natural logarithm, or 10.

Practical uses #

• Use base 2 to express a positive ratio in octaves.
• Use base 10 for decade-based scaling, or the natural logarithm for exponential DSP formulas.
• Pair it with Exp at the same base to compress and then restore a positive control range.

Things to know #

• The real-valued logarithm is defined only for inputs greater than zero.
• An input of 1 outputs 0 for every base.
• As the input approaches zero from above, the result decreases without bound; zero and the tested negative input displayed negative infinity.
• Natural Log reports approximately +20.72 for the magnitude 1,000,000,000, which was used to identify Power's finite sentinel value.

Technical details #

No Nitro implementation has been confirmed for this visible module. The behavior is described conservatively from module metadata and editorial research.

Officially defined modes are y = log2(x), y = ln(x), and y = log10(x) for positive x. In measured natural-log mode, 0.5 → -0.693, while both 0 and -1 displayed -∞ rather than a visible NaN. Both Power's positive cap and the absolute magnitude of its negative sentinel produced approximately ln(1,000,000,000) = 20.72.

Open questions #

• Repeat invalid-domain tests for bases 2 and 10 and probe very small positive inputs.

Version and sources #

Checked against Bitwig Studio 6.0.6. This page combines Bitwig's module metadata, the existing Grid course and guides, and Nitro analysis where the mapping is strong enough to support a technical statement.

Related material #

• Grid Modules course reference

Return to Bitwig Grid Modules or the Grid Modules course lesson.