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Common Audio Challenges & Solutions

This page details the most common challenges for sound recordists and how sound people can solve them. A skilled audio engineer in a larger production market having decades experience should be your first choice regardless of increased cost. I’ve seen and scanned every frequency range in the popular production areas as an audio tech, to cut problems.

Telephone – 1 720 299-2084

RF Interference

RF Interference commonly nicknamed RF is when a television channel, emergency response or other radio frequency distorts & impedes wireless mics/lavalieres. The source is in a matching or near frequency range that can cause dropouts, static, hissing noise or other problems. Cell phone signals also do this. The UHF spectrum this is legal goes from 400mhz to about 608 mhz. Or higher ranges from 1.8 to 2.0 ghz.

Some areas are difficult to work in with legal frequencies outside. Due to so many television stations and other sources. 470 to 608 mhz UHF takes a lot of scanning. Above 616 is illegal and will not benefit you in large events in the USA or when frequency coordinators are policing who uses of individual frequencies. Areas near lookout mountain require BlueTooth wireless as the RF clutter is bound to interfere with both UHF and VHF.

I have RF scans in all the major production markets and use 1.8 to 2 ghz range most of the time, as they lower UHF spectrum is overcrowded. To the point of constant RF. VHF is a simpler frequency allocation but still crowded. Scanning areas when you are out of home base can pay off.

! Never record sound with any RF interference. It cannot be removed in post most of the time without sacrifice to the fidelity of the recordings.

Solutions

Research the production areas in advance to see what the most crowded RF frequency ranges are. Bring gear out of those RF spectrums.
Scan with an open frequency then change your receiver and transmitters frequencies.
If the subject(s) are sitting, go to a hard wire lavaliere with a XLR connection.
Use wireless units like Sennheiser AVX100 or Rhode GO II wireless that scan and tune to open frequencies. Other Sennheiser, Lectrosonics and some others.Sennhesier can use 6 at a time of the AVX series without inter-modulation.
Use a shotgun mic if it works with the camera department.
Use hard wired lavalieres if the subjects are sitting or standing in place if there is unbeatable RF. These are called condenser mics that typically attach to an XLR cable.
Always have back-up audio gear.
Use UHF frequency lavalieres from 400mhz to 608mhz that can change frequencies. 470 to 608mhz are in legal use. Frequency Agile.
Use wireless lavalieres that operate in Blue Tooth and WI-FI ranges that can find open frequencies.

In larger markets and production populations RF challenges start around 470 mhz up to 960 mhz. This due to television stations, emergency response, private networks, and cell phone carriers. Other RF sources exist. Lookout Mountain, Golden and the surrounding areas are not ideal for VHF or UHF wireless. It’s better to use BlueTooth frequency wireless.

Change your frequencies in Lectrosonics.

Here on YouTube in various models.

Change Your frequencies in the Sennheiser G Series.

American TV Channel frequency reference.

World TV Channel frequency charts

USA FCC RF Charts frequency allocations. – a general summary not as descriptive

Dead or Damaged Audio Cables

A short in a cable will cause static pops or hisses or dropouts in signal. Resulting in loss of audio. For heavy use audio cables, a good audio guy will have a backup cable for the boom, camera connections & XLR cables. A good location sound technician will have back up equipment to many smaller or less costly items and the experience. I have ample extra audio gear as your sound engineer.

Solutions

Switch to an undamaged audio cable for your microphone or AF out cable.
Buy another one if readily available or rent one.
Always have back-up audio gear.
Hire a sound operator with backup audio equipment.

Noisy Audio Environments

An environment with loud noises can be a pain for a sound guy or woman using wireless and often shotgun mics. Sound mixers can assist with low cut & high pass filtering pending the noise.

Solutions

Point the shotgun mic opposite of the noise source by repositioning the talent & subjects.
Use tighter pattern shotgun mics angled away from the incoming noise.
Stop or pause the sources making the noise, politely.
Find another location or come back with the noise is controlled or finished.
Reduce the amount of noise producing sources by distance or less use.

No Sound but the Receiver has RF

As a location sound mixer I have seen this happen, and there are a couple things to investigate.

Solutions

The transmitter on the talent side is muted; un-mute it.
There is another more powerful RF source interfering with the receiver.
A damaged antenna on the transmitter and or receiver.
An improperly connected antenna on the transmitter and or receiver.

Example video without a sound recordist

Here’s a portion of a video where the production didn’t hire a sound recordist. Results in a buzzing noise recorded in the footage. Don’t take a chance with your production’s fate. Book an experienced sound guy like me.

I ended up cleaning the audio as the editor, however sound fidelity was lost. I did not shoot this video, but am using this for education. You can take your chances? Make sure your production is not wasted by bad audio; hire a sound person.

Let the Sound Recordist Do their job!

When RF comes up, a talent mutes the transmitter, or something gets interrupted; panicking solves nothing. Hiring an experienced sound recordist who can come up with a solution is better and will have been through the rodeo countless time.

Don’t blame the sound person if the talent mutes the transmitter or if RF comes. Un-mute or let the sound guy scan and switch frequencies and come up with a solution.

Behave professionally and don’t be afraid to ask questions about what’s going on.

Any honest sound person is going to do the best to get you the best field recordings.

Need Help, call, text or email

I’ve been a production professional and production sound recordist since the 1990’s but am still fresh in ideas with energy. I have helped other sound people, camera operators and others with advice by text, telephone and email. Google searching your problem will help. Trew Audio can help via telephone or email.

Contact Information

Telephone: Voice of Text: 1 (720) 299-2084

What’s App: Nick, MisterPhoton.com

My contact page with email address.

Skype, Nick Teti, Mister Photon Media, Colorado