Limiter level for sub and tops

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JRJ

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Topic: Limiter level for sub and tops
Posted: 10 November 2025 at 2:04pm

I want to set the limiters for my tops in my DCX2496 so that they are limited to the same level as my subs are, when they run out of steam.

The max SPL for my tops are 5dB higher then for my subs, within their respective usable frequency band.

The subs are set to -24dBfs to keep the power from the amp within the drivers power handling. And for the tops it's -17dBfs.

If I just drop the limiter for the tops to -22dBfs, I suppose the max SPL for the tops before the limiter kicks in will be the same actual max SPL as for the subs then?

njw

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Posted: 10 November 2025 at 7:47pm

I wouldn't get too hung up on the numbers, just set the balance between bass/mid/top as you like it and then set the threshold on the mid/top limiters so that they kick in at the same time as the bass limiters. Simple. Smile

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Posted: 10 November 2025 at 10:51pm

JRJ wrote:

I want to set the limiters for my tops in my DCX2496 so that they are limited to the same level as my subs are, when they run out of steam.

The max SPL for my tops are 5dB higher then for my subs, within their respective usable frequency band.

The subs are set to -24dBfs to keep the power from the amp within the drivers power handling. And for the tops it's -17dBfs.

If I just drop the limiter for the tops to -22dBfs, I suppose the max SPL for the tops before the limiter kicks in will be the same actual max SPL as for the subs then?

The limiters are not really there as gain controls, on the 2496 use the output gain on each band to balance the system. Then depending on the amp gains set the limiters.

I would run it up, have the amps on max, set the output gains to suit your ear. Then go into the limiter section of the dcx and wind the limiter down till the bar is sitting just above the signal peaks, then lower the output gain a couple of dB on each channel. Really the last thing you want with a dcx is it to be anywhere near hitting the limiters.. Also make liberal use of the input gain settings (especially if there's a pioneer sitting upstream.)

Edited by 4D - 11 November 2025 at 6:43pm

DMZ. "The bass was intense. Girls were literally running up to stand next to the subs"

Conanski

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Posted: 11 November 2025 at 3:33am

There is no way for us to know if that would be correct for your system, not enough info.

The advice in the post above yours is valid, next time you have the system running just bring the limiter threshold for the tops down so it activates at the same time as the subs.

JRJ

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Posted: 11 November 2025 at 8:03am

Thanks!

Maybe I was a bit unclear but the actual correct settings for the limiter in my system IS -24dBfs for the subs, and -17dBfs for the tops.

If set to this, both the subs and the tops will only get the juice they can handle from the amps.

However, at this maximum level of power comming from the amps to the speakers, the tops will play 5dB louder then the subs, making the sound very poor on bass if the volume is raised further when the limiter for the subs kick in.

So the idea was to just bring the limiter for the tops down 5dB more to "align" with the limiter for the subs.

I suppose that is basically what you're saying will work, just that I calculated it theoreticaly and you're saying how to do it IRL with the system up and running. Smile

And the output gain on each channel is ofcourse used to balance the subs against the tops Thumbs Up

JRJ

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Posted: 11 November 2025 at 8:11am

4D wrote:

Really the last thing you want with a dcx is it to be anywhere near hitting the limiters..

Could you please explain a bit more about this?

I've heard people say that the DCX2496 limiters are a joke, and other people say that they work perfectly fine...

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Posted: 11 November 2025 at 9:48am

I took the liberty of prompting Deepseek for a reply.. I would add that Specific to the dcx the artifacts introduced are particularly displeasing to the ear..

Deepseek.. You are a sound engineer running big sound systems explain why limiting the system to tightly can cause issues

Of course. Let's break this down. Think of me as your sound engineer, we're standing by the front-of-house console, and I'm explaining why I'm not just slamming the limiters on the system.

In simple terms, a limiter is an emergency brake for your sound system. Its job is to prevent the audio signal from exceeding a certain level, protecting your speakers from damage. However, setting this brake to engage too aggressively or too early (i.e., "limiting the system too tightly") causes a host of problems.

Here’s a breakdown of the issues, from the technical to the perceptual.

---

1. The Obvious Culprit: Dynamic Range Compression (Sucking the Life Out of the Music)

This is the most audible issue.

· What are Dynamics? Music and live performance have quiet moments and loud moments—the whisper of a vocal, the crack of a snare drum, the swell of an orchestra. The difference between the quietest and loudest parts is the dynamic range. This is what gives music emotion, impact, and power.

· What Happens with Tight Limiting? When you set the limiter's threshold very low, it activates constantly, not just on the extreme peaks. It aggressively clamps down on every loud transient.

· The Result: The music becomes a "brick wall" of sound. The exciting, punchy peaks are gone. The snare drum loses its crack, the kick drum loses its thump in your chest, and the overall sound feels flat, lifeless, and fatiguing to listen to. You've traded excitement and emotion for mere loudness.

2. Increased Listener Fatigue

This is a direct consequence of the above.

· A dynamically rich sound is easier on the ears. Your brain gets moments of rest between the loud impacts.

· A tightly limited, constantly loud signal gives your ears and brain no respite. This causes listener fatigue much more quickly. The audience might not know why, but they'll feel tired, irritable, or have a headache, and they'll likely start talking over the music because it's lost its engaging quality.

3. The Sneaky Power Drain: Suppressing Transients Robs Amplifier Headroom

This is a more advanced, system-based issue that many don't consider.

· What is a Transient? A transient is a very short, very high-energy burst of sound—the initial hit of a drum or the pick attack of a guitar.

· Power & Headroom: Amplifiers need a massive, instantaneous burst of power (current) to reproduce these transients accurately. This is what we call headroom—the amplifier's reserve power for these short bursts.

· The Counter-Intuitive Problem: When a limiter aggressively suppresses a transient, it doesn't just lower the peak; it often lengthens the energy of that hit. You're trading a short, high-power demand for a longer, sustained, medium-power demand.

· The Result: Instead of a brief, deep draw from the power supply, the amplifier is now asked to deliver a continuous, high average power. This can actually overheat the amplifier's power supply and output stages more effectively than the transient would have! You're avoiding a quick punch but signing up for a long, hard push that can cause the amp to go into thermal protection or fail.

4. Harmonic Distortion and Unpleasant Artifacts

Limiters are not perfect. When they work extremely hard, they introduce distortion.

· What is Distortion? In this context, it's the addition of frequencies that were not in the original signal.

· How a Limiter Causes It: The limiter's "gain reduction" circuit is working furiously to squash the waveform. This process generates Intermodulation Distortion (IMD), which creates dissonant, non-musical sideband frequencies.

· The Result: The sound becomes harsh, gritty, and unpleasant. Cymbals sound splashy and trashy, vocals become edgy and sibilant, and the overall mix loses its clarity. It's no longer clean and powerful; it's just a distorted mess.

5. The False Sense of Security and Hidden Damage

This is a classic pitfall for new system techs.

· The Thinking: "If I limit it tightly, my speakers are safe."

· The Reality: You are only protecting against one type of damage: over-excursion from a single massive peak. However, you are now likely running the system at a consistently high average level, which is the primary cause of thermal failure.

· Speaker Killers are Heat and Distortion: The voice coils in your speakers heat up with sustained power. Tight limiting allows you to push the overall level higher, pumping continuous heat into the coils. Combine this with the distortion artifacts mentioned above (which are essentially garbage signals), and you are literally cooking your speakers with a toxic soup of power and distortion, all while your limiter lights are blinking happily, giving you a false "all clear."

---

The Sound Engineer's Philosophy: The Limiter as a Guardian, Not a Tool

A seasoned system engineer views the limiter not as a tool for making things louder, but as a safety net or guardian.

We set it with a light touch:

· The threshold is set high enough that it only engages on the absolute, unexpected peaks—the mic drop, the feedback squeal, the rogue 10dB kick drum sample.

· It's the last line of defense, not the first tool for controlling level.

Our goal is to use the system's available headroom intelligently. We balance the mix so that the average level is strong and clear, leaving plenty of room for those dynamic, powerful transients to punch through without hitting the limiters. This results in a system that is both powerful and clean, and most importantly, sounds incredible without risking the very gear we're trying to protect.

So, in short: limiting too tightly makes your system sound worse, fatigues your audience, and can actually increase the risk of damaging your equipment. It's the hallmark of an inexperienced engineer.

Edited by 4D - 11 November 2025 at 9:48am

DMZ. "The bass was intense. Girls were literally running up to stand next to the subs"

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Posted: 11 November 2025 at 5:06pm

Adding to the above a lot of EDM has already been compressed & normalised to get maximum gain which in turn increases the importance of having the system limiters set correctly

DMZ. "The bass was intense. Girls were literally running up to stand next to the subs"

fudge22

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Posted: 11 November 2025 at 8:39pm

Maybe I was a bit unclear but the actual correct settings for the limiter in my system IS -24dBfs for the subs, and -17dBfs for the tops.
If set to this, both the subs and the tops will only get the juice they can handle from the amps.

However, at this maximum level of power comming from the amps to the speakers, the tops will play 5dB louder then the subs, making the sound very poor on bass if the volume is raised further when the limiter for the subs kick in.
So the idea was to just bring the limiter for the tops down 5dB more to "align" with the limiter for the subs.

The simple solution is that when your subs start limiting don’t increase the level. The tops only get louder because you keep increasing the level. If at 0.0001dB below the subs limiting the relative balance between subs and tops is fine, that is your limit. If stopping when you reach 10 on the volume control is not an option, an alternative to what others have suggested is putting a limiter on the full range signal before it gets to the DCX, which would keep all frequencies at the same level. Relying on the DCX to control signal levels is like using a multiband compressor when you actually need a single band compressor.

I've heard people say that the DCX2496 limiters are a joke, and other people say that they work perfectly fine...

There used to be a lot of hate for Behringer products, so it must sound shit – right?

However, it also depends on your perspective. Some people think that limiters should be inaudible. Others like me, think that they should sound so bad that it teaches the person controlling the level to show some restraint. Limiters were originally introduced in radio broadcasting. Transmitters had a strict maximum modulation level. Going over that could cause interference on nearby frequencies, as well as damaging expensive hardware. Limiters ensured that the broadcast signal never exceeded legal or technical limits. Limiters were not intended as an inaudible crutch for operators who don’t know when to stop turning up.

To quote a paper by M. T. Miles of Electro-Voice:

“Another method of limiting the voltage at the speaker terminals is to clip the signal. This method is preferable because the signal is affected only during the offending transient, and the signal path gain is instantly restored. While clipping is not a subtle form of distortion, speaker diaphragm crashing is much worse.

Wait! Electro-Voice advocating clipping to protect drive units. What heresy is that?

I took the liberty of prompting Deepseek for a reply..

TLDR, so I got Chatgpt to summarise in one paragraph.

Unfortunately, I forgot to specify the length of the paragraph, so here is Grok’s summary of the summary.

Overly aggressive limiting on a sound system may protect speakers from peaks but harms audio quality and equipment. It crushes dynamics, making music sound flat, lifeless, and fatiguing by creating a constant wall of noise. This reduces impact and emotional energy while increasing listener fatigue. Technically, it strains amplifiers by converting transients into sustained power demands, introduces harsh distortion, and drives speakers harder on average, leading to heat build up and thermal damage—despite a false sense of security. Instead, use limiters lightly as a safety net to catch rare spikes, preserving headroom, clarity, and musicality.

Adding to the above a lot of EDM has already been compressed & normalised to get maximum gain which in turn increases the importance of having the system limiters set correctly

If the signal is already overly compressed, the last thing needed is more compression. I would say that it increases the importance of knowing when to stop pushing the faders up.

P.S.

The title of the paper quoted above was:

An Electronic Loudspeaker Enhancement and Protection Device.

Conanski

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Posted: 12 November 2025 at 4:57am

JRJ wrote:

Thanks!

Maybe I was a bit unclear but the actual correct settings for the limiter in my system IS -24dBfs for the subs, and -17dBfs for the tops.

If set to this, both the subs and the tops will only get the juice they can handle from the amps.

So the idea was to just bring the limiter for the tops down 5dB more to "align" with the limiter for the subs.

I suppose that is basically what you're saying will work, just that I calculated it theoreticaly and you're saying how to do it IRL with the system up and running. Smile

Yes exactly.. the theoretical amount you need to adjust should work out to be correct or really close to what is needed to make the system sound balanced. And that is the correct limiting for your system, max power to all drivers rarely ever produces balanced sound, I don't know where people get this idea.

As for the claim that the DCX limiters sound bad.. I just don't get it. I have 2 of them in my system which routinely gets run right up into limiting by DJs, and I can't hear it. When I say " into limiting" I mean 6-8db over the threshold momentarily, it's not slammed 20dB into constant limiting.. that is just dumb and yeah that is going to sound bad. In my experience the DCX limiting does a very good job used this way.. the system just stops getting louder, there is no distortion or pumping, no obvious compression.

Edited by Conanski - 12 November 2025 at 5:00am