DM Amplifier Module Power & Limiting Parameters Reference Table
Step：  1. Set the DSP input and output signal at 0dB, 2. Open the Limiter，Set threshold as 0dB, 3. Adjust the compression ratio to achieve the required power output.
DM30				DM24				DM20
8Ω Power	4Ω Power	Ratio		8Ω Power	4Ω Power	Ratio		8Ω Power	4Ω Power	Ratio
1500W	2700W	0		1200W	2450W	0		1000W	1900W	0
1400W	2500	4%		1000W	1950	6%		900W	1800	2%
1200W	2200	5%		900W	1750	9%		800W	1600	6%
1000W	1850	10%		800W	1580	12%		600W	1200	14%
800W	1500	15%		600W	1150	19%		500W	1000	18%
600W	1100	21%		400W	800	26%		400W	800	21%
400W	750W	28%		200W	400W	43%		200W	400W	39%
200W	400W	42%		100W	200W	58%		100W	200W	56%
DM10				500W
8Ω Power	4Ω Power	Ratio		8Ω Power	4Ω Power	Ratio
900W		0		500W	980W	0
800W		2%		400W	780W	8%
600W		10%		300W	585W	17%
500W		14%		250W	490W	22%
400W		19%		200W	400W	27%
300W		25%		150W	295W	34%
200W		33%		100W	200W	46%
100W		50%		50W	100W	66%

For example，to set DM30 at Ratio 4%, it will be like the below image.

             

 

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— The Functions of Limiter Settings in Professional Power Amplifiers

In professional sound systems, the Limiter in the DSP (Digital Signal Processing) software acts as a safety barrier and fuse for the system. Its main purposes include:

– Loudspeaker Protection (Core Function): It prevents sudden signal spikes (such as microphone drops, instant feedback shrieks, or sudden audio bursts) from exceeding the maximum power capacity of the speakers. This protects the voice coils from burning out due to overheating and prevents mechanical damage to the diaphragms from over-excursion.

– Preventing Amplifier Clipping: When an amplifier reaches its output limit, it produces "clipping," which generates a large amount of harmful high-frequency harmonics that can easily burn out tweeters. A limiter keeps the signal below the amplifier's clipping line.

– Optimizing Listening Experience: When the system is occasionally overloaded, the limiter prevents the sound from shattering or distorting harshly, maintaining a relatively safe auditory environment.
 

— Explanations and Guide for the Four DSP Parameters

The four parameters you see are the core controls of a standard Compressor/Limiter. To make it function as a protective "limiter," you should set them according to the following logic:

1. Level (Threshold)

– Meaning: The dividing line where the limiter starts working. When the signal level is below this threshold, the DSP does not intervene; once it exceeds this value, the limiter engages immediatel

– How to set: This is the most critical parameter and typically requires calculation. Theoretically, it depends on the speaker's rated power (AES/RMS), speaker impedance, and the amplifier's voltage gain/sensitivity.

Safe Practical Method (Without Complex Calculation): Disconnect the speakers (unplug the speaker cables). Play standard pink noise or music through the system and gradually turn up the volume while watching the amplifier's front panel. When the CLIP (red light) on the amplifier just starts to flash, adjust the Level in your DSP software downwards (e.g., from 0dB down to -3dB, -6dB...). Stop when the amplifier's clip light just goes out, leaving only the green signal lights or safe yellow lights. This position is your safe Level threshold.
 

2. Ratio

– Meaning: The ratio of gain reduction applied to the signal once it exceeds the Level.

– How to set: Since we are configuring a "limiter" to protect the speakers, we need a hard "stop" rather than gentle compression.

Set this directly to ∞:1 (Infinity to 1), or the maximum value allowed by the software (such as 20:1, 50:1, or 100:1). This ensures that once the threshold is crossed, the output will never exceed the limit (commonly known as a "brickwall limiter").
 

3. Attack (Attack Time)

– Meaning: How long it takes for the limiter to fully pull the volume down after the signal exceeds the Level. It is measured in milliseconds (ms).

– How to set: * HF Drivers (Tweeters): Need extremely fast protection to prevent sharp transients from piercing the driver. Set it to Fast (1ms - 5ms).

MF/LF Drivers (Mid-Bass/Full-Range): Set it to Medium (10ms - 30ms). This leaves a tiny bit of transient punch for punchy drums while protecting the voice coil from sustained high power.

Subwoofers: Low frequencies have long wavelengths. If the attack time is too fast, it will distort the waveform. Set it to Slow (40ms - 100ms).
 

4. Release (Release Time)

– Meaning: How long it takes for the limiter to "let go" and stop compressing the audio once the signal drops back below the Level. It is measured in milliseconds (ms).

– How to set: * If the release time is too short (too fast), it will cause a noticeable, unpleasant "pumping" effect.

If it is too long (too slow), normal audio will remain unnecessarily quiet for a while after a loud peak passes.

Industry Golden Rule: The release time is usually set to 8 to 16 times the Attack time.

Recommended: 100ms - 200ms for full-range/tweeters; 400ms - 800ms or longer for subwoofers.
 

— Quick Settings Template (For General Full-Range Speakers)

If you need a quick, safe setup without doing deep acoustic calculations, you can apply this standard full-range speaker protection profile:

Parameter	Recommended Value	Note
Ratio	∞:1 (or Max)	Must be a hard limit for absolute protection.
Attack	10 ms	Balances musical transient punch with tweeter protection.
Release	150 ms — 200 ms	Delivers natural audio behavior without "pumping" artifacts.
Level	Fine-tuned based on the amp	Play dynamic music and set it right to the point where the amp just stops clipping (flashing red), then back it off by 1–2 dB for safety margin.

Ultimate Safety Advice: A limiter is only the "last line of defense"—it is not a cure-all. If the mixing console upstream is already clipping severely (red-lining everywhere) and sending a heavily distorted signal, the speaker can still burn out due to the DC components of the square waves, even if the DSP limits the overall volume. Maintaining clean gain staging throughout the entire equipment chain is always the best practice.
 

 

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