Chorus Depth Calculator
Convert your chorus effect's modulation depth and delay time into a percentage figure that represents the intensity of pitch variation. Use it when dialling in chorus settings to quantify how wide or subtle the effect will sound.
About this calculator
A chorus effect works by mixing a slightly delayed and pitch-modulated copy of a signal with the dry original, creating the illusion of multiple voices. The perceived depth of the chorus — how much pitch wobble you hear — depends on how large the modulation depth is relative to the base delay time. The formula used here is: depth (%) = (modDepth / delayTime) × 100. Both modDepth and delayTime are expressed in milliseconds. A higher percentage means the delay time varies more dramatically, resulting in a wider, more obvious chorus. A lower percentage produces subtle, transparent thickening. Typical chorus settings range from about 10% (lush but natural) up to 50% or more for dramatic, seasick warble effects.
How to use
Suppose your chorus plugin has a Delay Time of 20 ms and a Modulation Depth of 4 ms. Step 1 – Enter Delay Time = 20 and Modulation Depth = 4. Step 2 – Apply the formula: depth = (4 / 20) × 100 = 20%. Step 3 – A 20% depth indicates a moderate chorus effect — noticeable pitch movement without being overwhelming. If you want a subtler sound, try reducing modulation depth to 2 ms, which gives 10%. For a lush, wide effect, increase to 6 ms for 30%.
Frequently asked questions
What is modulation depth in a chorus effect and how does it affect sound?
Modulation depth is the maximum amount by which the chorus's internal delay time fluctuates above and below its base value, measured in milliseconds. As the LFO sweeps, the delay time oscillates, which causes the pitch of the delayed copy to rise and fall slightly — this is the 'wobble' you hear. A larger modulation depth means bigger pitch swings and a wider, more dramatic effect. A smaller depth creates subtle thickening that sits naturally in a mix without calling attention to itself.
How do I calculate chorus depth percentage from delay and modulation settings?
Divide the modulation depth (in ms) by the base delay time (in ms) and multiply by 100 to get the percentage. For example, a 3 ms modulation depth on a 15 ms delay gives (3/15)×100 = 20%. This percentage tells you how widely the pitch is modulated relative to the base delay. Higher percentages mean more pronounced pitch movement, while lower percentages result in transparent, natural-sounding thickening.
What chorus depth percentage should I use for vocals versus guitars?
For vocals, a low depth of 5–15% typically works best — enough to thicken and widen the voice without introducing obvious pitch wobble that would sound out of tune. For electric guitars, 15–30% is common, giving that classic 80s chorus shimmer. Bass guitars usually benefit from very low depths (under 10%) to preserve low-end clarity. Lead instruments in general prefer subtler settings, while pads and rhythm parts can handle more depth before sounding unnatural.