Paleness, "Tears," and Other Distortions in FM Audio

I am Ricardo Gurgel, an engineer, and the following text comes from another text of mine in Portuguese, where I explained the audio quality in FM stations and the people and resources we need to rely on to find qualified solutions.Many broadcasters, especially community radios (25 W) and low-power commercial stations (up to 300 W), invest heavily in high-end microphones, cabling, and sound mixers. However, this investment may be futile without essential knowledge: beyond the transmitter, stereo generator, mixer, and microphones, there is a fundamental piece of equipment for broadcast sound quality—the audio processor for broadcasting.

Without a well-adjusted audio processor, all high-end equipment loses efficiency. The result is dirty, distorted, and lifeless sound, along with the risk of penalties from ANATEL due to overmodulation. Excessive modulation does not mean louder sound but rather an unpleasant audio experience that can (literally) drive listeners away.

What Does an Audio Processor Do?

The audio processor analyzes and separates sound into different frequency bands, adjusting each one to ensure an ideal balance. It reduces frequencies that could cause distortion by exceeding 100% modulation and amplifies elements that would otherwise be inaudible. This all happens within milliseconds, resulting in clean, powerful, and professional sound.

Often, audio at 120% modulation does not sound louder than properly processed audio at 99.99%. On the contrary, correct processing provides greater clarity and definition in highs, mids, and lows, while an uncontrolled transmission generates only noise and discomfort, causing listeners to seek a more pleasant alternative.

An audio processor also includes filters that remove frequencies incompatible with FM transmission. In other words, even if a file sounds good on a computer, sending it to the transmitter without passing through a processor’s filters will cause these incompatible frequencies to interfere with the carrier, resulting in distortion.

Avoiding Fines and Ensuring Quality

Operating within the modulation limits set by regulations not only prevents fines but also retains the audience. The audio processor ensures that the station operates within technical standards, avoiding distortions and interference that could disrupt other stations.

Volume vs. Peaks

Imagine a classroom with 100 students. If only one of them screams while the others speak softly, the overall sense of volume will be lower than in an environment where everyone speaks at a balanced level. However, that single scream exceeds acceptable limits and causes distortion. Similarly, an audio processor levels volumes, providing uniform and powerful sound without exceeding modulation limits, thus avoiding distortions and interference.

The Cost of Quality

In the past, achieving excellence in broadcast audio required investments of tens of thousands of dollars. Often, even with high-end equipment, improper adjustments compromised the sound, making the transmission unpleasant. Major brands like Orban and Omnia dominated the market with high-performance equipment, but today, equally competitive options exist, including domestic models.

Orban, comparable to Boeing in the audio processor market, faces challenges in keeping up with Omnia, which can be likened to the powerful Airbus. In the national market, Biquad, comparable to Embraer, stands out with its DAP4 processor, which, when well-configured, delivers excellent sound quality. For smaller stations, Apel provided an incredible solution with its AP-07X, an affordable and efficient model. Unfortunately, a lack of communication with small radio stations caused Apel to lose a promising market.

How to Achieve Competitive Audio at Low Cost?

Today, affordable audio processors are available, and when configured by experienced professionals, they provide a unique sound signature for each station. The secret lies in selecting a good "preset expert," someone with a keen ear and technical knowledge to optimize the equipment’s performance.

The Best Installer and "Preset Expert" for Low-Cost Audio Processors

This is undoubtedly a personal experience, but I consider it essential to share. For those seeking excellence in broadcasting, I recommend a professional with integrity and a passion for radio—someone who has always stayed in touch, made a point to share progress, and pushed the boundaries in pursuit of the highest audio quality.

My recommendation as a professional is Ewerton Douglas

Journalist, administrator, geographer, and researcher in transmission technologies.

He works at the Correio Communication System, based in Guarabira/PB, providing support to various stations in the region.

With an affordable investment, Ewerton delivers exceptional audio quality. His work is widely recognized and recommended, always exceeding expectations.

Sound quality may be subjective, but the results speak for themselves. To prove the excellence of Ewerton Douglas' work, I have provided a player and links to listen to Mega FM and Guarabira FM, which use his audio processors.

Contacts:🔗 Instagram: @ewertondouglastv

Two Stations with Different Presets Configured by Ewerton Douglas

🎵 Mega FM

📻 Guarabira FM (Correio Communication System)

I invite you to experience these stations using high-quality audio equipment. For an even more immersive perception of the audio achieved with these processing configurations, I suggest tuning in via Bluetooth in your car.

This test will help you understand how precise tuning in a station’s sound signature can have significant impacts, such as:

✅ Increased listener retention

✅ Growth in audience base

✅ Financial benefits from higher engagement

Enjoy and feel the difference! 🎧🚗📡