Transmitting audio signals over long distances is a significant challenge, especially in professional audio systems, studios, live performances, and broadcasting. Cable resistance, electromagnetic interference (EMI), radio frequency interference (RFI), and other factors can degrade signal quality and cause unwanted noise. In this article, which is prepared with the knowledge and experience of Ülkü Kablo, the cables that should be used to minimize losses in long-distance audio transmission, cabling techniques and other factors to be considered will be discussed in detail.
1. Balanced Connections and Cables (XLR & TRS):
- Importance of Balanced Connection: One of the most critical factors in long-distance audio transmission is to use a balanced connection. Balanced connections transmit the signal in two opposite phases, largely eliminating common-mode noise along the cable. At the receiving end, the noise is canceled out as these two signals are combined again.
- XLR Cables: XLR cables are the most commonly used type of cable for stable connections between microphones, mixers, audio interfaces, and other professional audio equipment. It has three-pin connectors: Ground, Hot and Cold.
- TRS Cables: Cables with 1/4 inch TRS (Type-Ring-Sleeve) connectors can also be used for stable connection. They are generally preferred for line-level signals.
- Avoiding Unbalanced Connections: Unbalanced connections (for example, RCA or TS cables) are much more sensitive to noise and can cause signal loss and noise problems over long distances. Therefore, unstable connections should be avoided over long distances.
2. Cable Thickness (AWG):
- AWG (American Wire Gauge): It is a standard used to measure cable thickness. A lower AWG number means thicker wire.
- Advantages of Thicker Cables: Thicker cables offer less resistance, which reduces signal loss. Over long distances, thin cables can cause more signal loss.
- Recommended AWG Values for Long Distances: For long-distance audio transmission, 16 AWG or thicker cables (e.g., 14 AWG or 12 AWG) should be preferred.
3. Cable Shielding:
- Importance of Shielding: Cable shielding protects the cable from external factors such as electromagnetic interference (EMI) and radio frequency interference (RFI). These interferences can be reflected in the audio signal as noise.
- Different Types of Protection:
- Braided Shielding: It is a type of shielding made of thin wires. It is durable and flexible and provides good protection.
- Foil Shielding: It is a type of shielding coated with aluminum foil. It is lightweight and effective, but not as durable as braided shielding.
- Braided and Foil Combination: Braided and foil shielding are sometimes used together to provide the best protection.
- Uses of Shielded Cables: Especially in environments where electromagnetic interference is intense (for example, near electrical cables), well-shielded cables should be preferred.
4. Connector Quality:
- Effect of Connectors: The quality of the connectors can also affect signal transmission. Bad connectors can cause signal loss, noise, and connection problems.
- Features of High Quality Connectors:
- Sturdy Construction: It should be durable and long-lasting.
- Tight Fit: It should provide a tight and reliable connection between the cable and the equipment.
- Gold Plated (Optional): Gold-plated connectors are more resistant to corrosion and can provide a better transmission, but are often more expensive.
5. Cable Laying Techniques:
- Keeping Cables Tidy: Laying cables neatly and keeping them organized prevents tangles and improves signal quality.
- Keeping Electrical Cables Away: Keeping audio cables away from electrical cables reduces electromagnetic interference.
- Avoiding Wire Harnesses: Avoiding collecting cables carrying different types of signals in the same bundle prevents interference.
- Cable Wrapping Techniques: Wrapping cables correctly prevents damage and prolongs their lifespan.
6. Distance & Signal Amplification:
- Distance Limits: As the cable length increases, the signal loss also increases. At very long distances (e.g., more than 100 meters), it may be necessary to use signal boosters (line amplifiers) or converters (e.g., analog-to-digital converters).
- Signal Boosters: They compensate for signal loss over long distances by raising the signal level.
- Transducers: They convert an analog signal into a digital signal, providing lossless transmission over long distances.
7. Other Factors:
- Impedance Matching: Matching the impedances of the source and receiving equipment is important for signal transmission.
- Cable Testers: Cable testers can be used to ensure that cables are working correctly.
Summary:
In long-distance audio transmission, balanced connections, thick-cross-section and well-shielded cables, high-quality connectors, correct wiring techniques, and signal boosters or converters should be used if necessary to minimize losses. By paying attention to these factors, you can ensure a high-quality and lossless sound transmission even over long distances. You can contact Ülkü Kablo for our long-distance audio transmission solutions.
