This page discusses amplifying feedback cycles and the factors that limit them, primarily using a sound system as an example.

Most people have experienced audio feedback, that sudden, piercing screech from a sound system. Understanding audio feedback provides a foundation for understanding the use of amplifying feedback in two areas covered on this website: (1) the development of human problems, and (2) escalating climate change.

Here is the amplifying feedback cycle that drives audio feedback. camping.

In this audio cycle: (1) the microphone picks up a resonant pitch, which tends to (2) increase the amplifier output of this pitch, which tends to (3) increase the loudspeaker volume of the pitch, which tends to (4) increase the microphone input volume of the pitch, and (5) the cycle repeats.

The louder the screech gets, the louder it gets.

Feedback cycles show tendencies.

I use the word tends because numerous factors can intervene and break a causal link in the cycle. Feedback diagrams show what tends to happen.

The nature of any amplifying feedback cycle

Any amplifying feedback cycle has a circular sequence of causal links between system attributes, in which an increase or decrease in one attribute influences the next, which then influences the next, creating a ripple effect around the cycle that amplifies the initial change, and then the cycle repeats (Capra, 1996, p. 56).

Feedback cycles reveal organisation.

A feedback cycle displays the organisation of the system, as distinct from its physical structure (Capra, 1997, p. 63).

Terms describing amplifying cycles

Here are some terms I use to describe amplifying feedback cycles.

Time taken by the audio cycle

In this circular sequence of causal links, each physical change takes time and extends the cycle. In audio feedback, there are three causal links:

• The link between the loudspeaker and the microphone is sound, which travels at 343 metres per second, so there is a small delay. Say the loudspeaker is 10 metres from the microphone, the sound travels that distance in 3 hundredths of a second.
• The link between the microphone and the amplifier is a rapid electrical connection, like when you flick a light switch, and the globe lights up; it seems instantaneous, but there is a small delay.
• The link between the amplifier and the speaker is another rapid electrical connection.

Each causal link takes time as change ripples around the cycle. The rapid speed of the causal links in an audio system means that in small performance spaces, there is negligible delay between what you see and what you hear. The downside of the rapid links is that the feedback screech can rapidly escalate to an unbearable level.

Cycle Dominance

A feedback cycle is dominant when each of its causal links occurs sequentially, with no additional delay. Using the concept of dominance makes the description of the cycle more compact:

While the audio cycle is dominant: (1) the microphone picks up a resonant pitch, which (2) increases the amplifier output of this pitch, which (3) increases the loudspeaker volume of the pitch, which (4) increases the microphone input volume of the pitch, and (5) the cycle repeats.

Cycle Dormancy

When an extra delay occurs in a cycle link, the factor causing the delay gains dominance, and the cycle becomes partially active or inactive/dormant.

No amplifying cycle can continue indefinitely. It will become dormant due to (1) an external influence pausing the amplification, or (2) the uninhibited amplification continuing until it eventually exhausts a necessary resource and so pauses itself. Ways the audio cycle could pause and become dormant include:

• An external influence breaks a causal link. It’s normally the sound operator who hears the screech and cuts the amplifier. They break the cycle by stopping any amplifier output at the resonant frequency.
• The cycle exhausts a necessary resource when a component reaches an upper performance limit. For example, the amplifier reaches its upper power limit, and so cannot produce a “louder loudspeaker volume”. The amplifying cycle would stop, having completed its transformation of the system, leaving a high, constant volume screech.
• The cycle exhausts a necessary resource when a component breaks. For example, the loudspeaker blows a fuse. The vicious cycle would stop, having completed its transformation of the system, leaving silence, not “louder loudspeaker output”.

Stopping the feedback

Forcing the resonant frequency to zero in the microphone input, amplifier output, or loudspeaker output will stop the feedback screech. Reducing any one of these elements to zero will bring the other two elements to zero and stop the amplification cycle.

However, even the slightest reoccurrence of the resonant frequency can reactivate the feedback cycle and regenerate the feedback screech.

As an alternative, you could modify the system to prevent the amplifier from amplifying the resonant frequency, breaking the feedback loop at its source.

Discussion of other vicious cycles

To see how vicious cycles organise other systems, see:

• A psychodynamic gambling vicious cycle.
• Arctic cycle

Maruyama & his Second Cybernetics

Maruyama (1968) revolutionised systems theory by focusing on amplifying feedback cycles and their creative nature. He called his theory “the second cybernetics”, in contrast with earlier cybernetics, which focused on the destructive nature of amplifying feedback and mechanistic, damping feedback cycles. According to Maruyama:

• Amplifying feedback cycles are widespread (p. 304).
• Amplifying feedback cycles can disrupt the existing order and create a new order. For example, rock weathering is an amplifying feedback process that is (1) a vicious cycle in that it destroys rock, but also (2) a creative, virtuous cycle in that it creates fertile soil and forests (p. 305).
• These feedback cycles interact and can support or counterbalance one another, producing stability, oscillation, or transformation. (p. 312).
• Amplifying feedback cycles can occur between people and cause problems; for example, two aggressive individuals can easily escalate a misunderstanding into a physical fight.
• These cycles can also occur within a person, causing problems. For example, reduced self-confidence can lead to poor performance, which in turn can further reduce self-confidence (p. 312).
• In psychotherapy, the goal should be to break vicious, damaging feedback cycles underlying the presenting problem and to initiate virtuous feedback cycles that alleviate the problem (p. 312).

Alternative names for feedback cycles

You can call an amplifying feedback loop a:

• Positive feedback,
• Deviation amplifying mutual causal process (Maruyama)
• Self-amplifying feedback loop,
• Self-reinforcing cycle,
• Vicious cycle, and
• Virtuous cycle

You can call a damping feedback loop a:

• Negative feedback,
• Balancing feedback,
• Stabilising feedback, and
• Deviation counteracting mutual causal process (Maruyama)

Amplifying feedback & other influences

Here is a more detailed consideration of the things that influence amplifying feedback cycles.

When considered in isolation, an amplifying feedback cycle appears capable of continuing indefinitely. However, an unimpeded amolifying cycle will eventually exhaust some necessary resource and pause. Some influences reinforce the cycle, while others constrain or counteract it. Identifying these additional influences is essential for understanding the system.

The following table provides an overview of these influences on a considered amplifying feedback cycle.

Inhibiting amplifying feedback

First, consider the things that can inhibit an amplifying feedback cycle.

Inhibitor: A damping feedback cycle.

A damping feedback cycle can control an amplifying feedback cycle. Damping reduces the deviation of a system variable from its target value. Damping feedback maintains the system, whereas amplifying feedback tends to revolutionise the system.

Consider the damping feedback cycle that constrains the audio feedback amplifying cycle. It is the sound operator who hears the feedback escalating and adjusts the controls to damp it. Here is a diagram of the damping feedback cycle.

More Deviation: Excessive Loudspeaker volume Less		More Control: The operator reduces the amplifier’s power. More

In this damping cycle, the upper arrows show (1) “more excessive volume” tending to cause (2) “more control”, while the lower arrows show that this increased control tends to cause (3) “less excessive volume”.

You can think of this applying to gambling. For people who are in control of their gambling, when they have spent too much time or money, they leave the gambling venue. Their damping feedback cycle limits their excessive gambling.

The nature of any damping feedback cycle

In general, a damping feedback cycle has a circular sequence of causal connections, as does the sound system damping cycle shown above. The cycle differs from an amplifying feedback cycle because, in a damping cycle, a deviation in one system attribute, such as a boat’s deviation from its target course, triggers a corrective action that reduces that deviation.

By contrast, the opposite occurs in amplifying feedback, where an increase in one system attribute causes a further increase in that attribute.

Sailing boat damping cycle diagram

The steering of a sailing boat is another example of a damping feedback cycle. Here is this damping cycle.

More Deviation: The sailing boat heads to the right of the target direction. Less		More Control: The sailor pushes the tiller further to the right. More

In this damping cycle, the upper arrows show (1) more deviation to the right of the target tends to make (2) the sailor push the tiller more to the right. The lower arrows show that this increased control tends to cause (3) less deviation of the boat to the right.

Inhibitor: Other feedback cycles

Some amplifying feedback cycles can weaken others. While many vicious cycles can drive a client’s problem, say, problem gambling, activating an alternative interest, such as gardening, sets up virtuous, amplifying feedback cycles that support the alternative activity and counter the vicious problem-gambling cycles. Any weakening of a vicious gambling cycle is a move towards recovery.

A simple audio system has no other feedback loops, so consider the amplifying feedback cycle of foxes breeding, which inhibits the amplifying feedback cycle of rabbits breeding. Here, three feedback cycles interact.

This predator and prey example shows the interaction of only three feedback cycles and this creates a complex system. The understanding of human behaviour presented here involves a vast number of feedback cycles, a highly complex system.

Here is the rabbit breeding cycle.

More Rabbits More		More Rabbit Breeding More

While this breeding cycle dominates: (1) more rabbits tend to produce (2) more rabbit breeding, which tends to produce (3) more rabbits, and then (4) the cycle repeats.

The fox-breeding cycle has precisely the same form as the rabbit-breeding cycle:

More Foxes More		More Fox Breeding More

Now, foxes prey on rabbits, as shown in the following cycle.

More Foxes Fewer		Fewer Rabbits Fewer

In this cycle: (1) more foxes predating tends to produce (2) fewer rabbits, which tends to produce (3) fewer foxes, which tends to produce (4) more rabbits, which tends to produce (5) more foxes, and then (6) the cycle repeats.

Mathematical models of predator-prey populations predict that these populations tend to oscillate, and nature reflects this phenomenon. See the Wikipedia entry on the Lotka-Volterra equations.

This example shows that amplifying feedback cycles interact with one another in a complex fashion. Part of this is that the fox breeding cycle tends to weaken the rabbit breeding cycle.

Inhibitor: External events

External events can disrupt an amplifying feedback cycle.

In a sound system, an electrical power failure would disrupt the audio feedback. (This would be an unlikely occurrence.)

For a gambler, many external events can interrupt their gambling, e.g., a car accident injury.

Reinforcement of amplifying feedback cycles

Reinforcement: an amplifying feedback reinforces itself

An amplifying feedback is self-reinforcing. Unimpeded, it transforms its system, destroying the old system and creating a new one.

The audio feedback, if unimpeded, could hit a continuous maximum volume or break the sound system. Both these possibilities are transformations that would leave the event without a usable sound system.

Reinforcement: a group of amplifying feedback cycles

Other amplifying feedback cycles can reinforce the amplifying cycle under consideration, forming a group of mutually reinforcing cycles. This reinforcement occurs in the amplification of problem gambling and global heating, but not in the simpler sound system.

Reinforcement: External events

External events can reinforce an amplifying feedback cycle.

For audio feedback, this reinforcement is not likely. However, for other systems, such as global heating, this is the critical issue. Humans’ burning of fossil fuels, an external influence on the natural climate system, has triggered global warming and poses a risk to life as we know it on planet Earth.

Other features of amplifying feedback  

Here are two other features of amplifying feedback cycles

Amplifying feedback & rapid change

Once an amplifying feedback cycle becomes and remains dominant, it brings escalating change, initially slow and then explosive, until the transformation it initiates reaches a limit and the amplifying cycle stops.

For example, when a person in a chair leans back past the tipping point, a vicious cycle takes hold. The rotational energy increases more and more rapidly as the chair tips. The only way to stop the vicious cycle is (1) an external intervention, e.g., someone catching the chair, or (2) the cycle running its course and hitting a limit when the chair hits the floor.

See the “Tipping Point” page on this website.

Reversibility

Some amplifying feedback cycles are reversible as they can amplify changes in either direction.

The amplifying feedback cycle driving the audio feedback screech is irreversible. If a person put their hand over the microphone, reducing the microphone’s input volume, the cycle would not produce further decreases in volume. It would continue to increase the volume.

The Arctic sea ice spiral is currently amplifying global heating, but if cooling were to occur, it could also amplify global cooling. See my page on the Arctic sea ice spiral.

A self-organising system

Systems that receive a continual input of energy can become self-organising. For example, the sun provides the energy that drives the water cycle with its evaporation, rainfall, and river flow. This energy shapes the character of rivers as people know them, creating recurring rapids and eddies that appear depending on water levels (Capra, 1996).

I propose that the damping and amplifying feedback cycles that organise a person’s life, their actions, feelings and ideas, form a self-organising system that continually shapes a person’s character.

See my page on Self-organising human functioning

Conclusion

When I worked as a problem gambling counsellor, I found amplifying feedback cycles useful for understanding and assisting my clients. The cycles help understand what drives and resolves problems. Then I realised that other amplifying cycles were driving global heating – and that systems theory applies to any system.

In summary, here again is the overview of the influences on any considered amplifying feedback cycle.

Amplifying feedback cycles do not exist in isolation. Recognising how other influences can increase or decrease the impact of these cycles enhances the credibility of systems theory and our ability to understand the impact of amplifying feedback in our lives and on our planet.

Counselling Pages & References

The introduction to my counselling pages includes:

• Links to the other counselling pages, including those describing how this approach relates to other counselling practices and theories, see the top of the introduction page
• References for all the counselling pages, at the end of the introduction page.

First loaded Nov 2025. Updated: 13 April 2026