Latency - Facts, Fiction and Perception

Summary

In this video, the host breaks down the concept of latency in digital guitar modeling systems, explaining how it’s the time delay between when sound enters and exits a system. The speaker clarifies common misconceptions, such as confusing preset switching delays with latency, and emphasizes that small amounts of latency (under 15 milliseconds) are usually imperceptible to most players. Through real-time examples and experiments, the video highlights how digital systems, including effects pedals and modelers, have minimal latency, which most musicians won’t notice unless it significantly impacts the tactile feel of playing.

Takeaways

• 😀 Latency refers to the time delay between when audio enters and exits a system, such as when using digital effects or modeling systems for guitar.
• 😀 Latency is often misunderstood and should not be confused with other delays like preset switching lags in digital modeling equipment.
• 😀 The human ear cannot discern the source of latency, whether it's from analog-to-digital conversion or other processes.
• 😀 Latency does not affect the quality of the tone or sound, but it can impact the tactile feel and playing experience, especially in guitar setups.
• 😀 A small amount of latency (e.g., 15 milliseconds) is generally imperceptible to most players, though some may still find it noticeable depending on personal sensitivity.
• 😀 The threshold for perceiving latency differs from person to person, with 10 milliseconds or more often being the limit for noticeable delay in digital systems.
• 😀 The 1 millisecond = 1 foot rule is often used to estimate latency distance, with a typical digital pedal having 2-5 milliseconds of latency.
• 😀 Players using multiple digital pedals with latency may start to notice cumulative delays, especially without an analog dry path.
• 😀 Feedback-related latency can affect where the sweet spots for infinite sustain are, potentially requiring adjustments in performance or setup.
• 😀 Some players may prefer analog over digital modeling due to latency concerns, though this is often more about personal preference than technical limitations.
• 😀 Despite some claims, most players cannot reliably detect latency differences of 1-2 milliseconds, as human perception tends to be less sensitive to such small changes.

Q & A

What is latency in audio systems?

Latency is the time it takes for audio to enter a system, be processed, and exit it. Essentially, it is a time delay or time shift between input and output.

Does latency affect the sound quality of a guitar?

No, latency does not impact the tone or quality of the sound. It only introduces a time delay, which can affect the feel of playing but not the audio quality itself.

What is the difference between latency and switching lag?

Latency is the time delay of the audio signal, whereas switching lag refers to a delay when changing presets or turning on a system. Switching lag is not technically latency.

How do humans perceive latency?

Human perception of latency varies slightly, but generally, small amounts of latency (like 2–3 milliseconds) are imperceptible. The tactile feel when playing an instrument is what primarily affects perception.

What is the threshold of latency that is typically imperceptible?

Based on the speaker's experiment, latency around 14–15 milliseconds is generally imperceptible. Anything above 100 milliseconds becomes very noticeable and disruptive.

How does speaker distance relate to latency?

A general rule is that 1 millisecond of latency is roughly equivalent to standing 1 foot away from a speaker. For example, 15 milliseconds of latency would feel like standing 15 feet from a speaker.

Can using multiple digital pedals increase perceived latency?

Yes, each digital pedal adds a small amount of latency (2–5 milliseconds), and when multiple devices are used together, the total latency can become noticeable.

Do digital modelers like Axe-FX introduce noticeable latency?

High-quality digital modelers typically introduce only 2–3 milliseconds of latency, which is below the threshold of human perception and generally imperceptible during play.

In what situations does latency become a real problem?

Latency becomes problematic when it is high enough to disrupt tactile interaction with an instrument, affects feedback spots in live performance or studio setups, or accumulates through multiple digital conversions.

Why do some players feel uncomfortable with digital modelers even if latency is minimal?

Discomfort is often due to personal bias or preference rather than actual latency. The feeling of not 'vibing' with the rig may be psychological rather than technical.

Can latency affect feedback during live performance?

Yes, small amounts of latency can slightly change the location of feedback 'sweet spots' on stage, which can be important for precise feedback control.

How can high-end digital gear minimize latency?

High-end digital pedals or interfaces often include analog dry paths or direct digital connections to bypass unnecessary conversions, reducing added latency.