Live Sound Now: January 2024

Knowledge, Skills and Training for Live Sound Engineers

So here is a not so short post about all the things that I think are necessary to pursue a successful career as a live sound engineer. Rest assured none of this can be learned quickly, some things take a lot of study time and significant help from more experienced mix engineers. A lot rests on experience and how to learn from mistakes as well as good results. Live Sound mixing is a life long career that requires continuous learning.

Knowledge

For anyone working with technical equipment in a live sound environment it really helps to have some basic high school education in physics and math. Here is a list of other things that it is pretty necessary to know.

a) Audio and Acoustics

What the physical properties of sound are, simple harmonic motion, reflection and absorption, resonance, pitch, wavelength, comb filters and reverberation. It really helps to listen hard enough in larger rooms to train your hearing perception of what different types of rooms, surfaces and their acoustic properties actually sound like.

Microphone operating principles and the properties of the different types of capsules and what type is best for different applications. Loudspeaker operating principles and the properties of the different types of drivers, horns and enclosures. On and off axis response of speakers and arrays. Audio feedback. Hearing health and protection.

b) Audio Engineering

Basic analogue electronic circuits, complex impedance, balanced and unbalanced circuits, the relationship of source and termination impedances, frequency and phase response, signal and group delay, voltage and current amplification, use of transformers. How to handle signal level measurements, metering and dB scales. Wire types, specifications and applications of the different types.

Basic digital audio concepts including A/D conversion, sampling rates, oversampling, bit depth and digital metering and how that is different from analogue metering standards.

Signal paths, routing, summing and processing of audio signals from source to audience. Optimisation of signal levels and signal to noise ratios.

The standards for and differences between the many different transmission methods, connectors, cable and signal levels used in audio.

c) Computing and Networks

Competence in at least one major Operating System (Windows, Mac, Linux) and familiarity with Excel spreadsheets and Microsoft Word. Working knowledge of networking protocols, switches and routers, IP addressing and routing, wifi.

A good working knowledge of at least one major recording software package.

d) Musical Instruments

The different classes of instruments and how they work, the specific playing techniques and which parts of each instrument emit sound. How musical instruments sound, singly and in an ensemble, when played without amplification. What the common band and ensemble formats are. Best practices for mic selection and placement. The more familiarity an engineer has with different instruments, how they are played and what they sound like, the easier it is to get a good amplified sound. Understanding basic music theory is a great help especially a clear understanding of song structures, key relationships, harmony and rythmn.

e) Music

It seems so obvious but is rarely discussed by educators. In order to mix music an engineer needs to know what that music is supposed to sound like. Orchestral music mixing is significantly different from rock or dance music. Latin music has significantly different balances than rock or classical music. Chinese opera and Vietnamese folk music are very challenging for most western mix engineers. Music mixing requires a good knowledge of many different styles, types and periods of music. That mandates a lot of careful, enlightened listening and learning with a very open mind. If I am not familiar with a genre of music I try to find a musician or producer who is, they are usually very willing to give suggestions and listening lists.

f) AC Power

Basic electrical distribution systems including common multi-phase and multi-voltage connections, operating current and voltage standards and connector types. Some familiarity with the NEC standards for distribution and safety procedures when connecting and using electrical power. Familiarity with European electrical standards and connection types is helpful. As major production companies develop world wide markets for touring systems so more are adopting power systems that are compatible with European and North American standards.

g) Stage Craft

Knowledge of theatrical protocols for stage operations, show production and the roles of various theatrical technicians, back of house and front of house staff. Common stage naming conventions and locations. How to conduct yourself on and off stage during the various phases of show setups, rehearsals, show and strike. Basic understanding of the IATSE union processes and relationships to the venue and your show. How to be safe on stage and off. Stage plots and input lists preparation, what information to include. (See an earlier blog post in this series that discusses these items in detail.

h) Rigging

Nearly all touring audio systems are flown and even if the mix engineer is not directly responsible for rigging the speaker system it still helps to have some knowledge of rigging, especially when there is a challenging venue structure or potential safety issues.

Rating of different steel sizes, shackles, crosbies, nicopress and swages, slings, fly frames and box to box connection. Safe use of motors and controllers. Standard rigging practices and where they differ in various locations throughout the world. Where the legal responsibilities lie for safety of rigged equipment.

i) Health & Safety

The work of staging a performance can be hazardous both on stage and in other parts of the venue. Knowing stagecraft and theatrical procedures helps protect you as does a permanently “heads up” attitude at all times. There are obvious things like not standing beneath equipment whilst it is being rigged, wearing a hard hat at appropriate times, using gloves, lifting in a sensible manner and letting certified electricians do the power connections. But there are less obvious threats including dubiously stacked speakers, frayed or damaged wiring, any number of trip and head bang hazards, dark stages in general, elevators or lifts in a lowered position, the list is very extensive. Most important is to recognise danger and to call it out so everyone in your crew and all other workers around you know that there is a dangerous situation.

The other part of this is personal safety. Live sound work involves long hours, bumpy bus rides sleeping in bunks, snatched meals and a stressful work environment. You need to train yourself to manage stress in a healthy way, get enough sleep whenever you can and avoid the pitfalls of a rock n roll lifestyle including alcohol and drug abuse. Regular work outs, meditation, yoga and using your days off to relax properly are great ways to keep it together.

Skills

a) Music Mixing

Seems obvious, but there are mixers out there who got the job for reasons other than they were good mixers. Maybe they are a relative or trusted friend of someone in the band. There are also mixers who have basic skills but have never advanced their art or changed their methods. Mixing takes skill and practice and there is always something new to learn. I strongly recommend that live sound engineers do some studio recording as a way to hone their skills, even hanging around in a studio helps sharpen your listening skills and appreciation for how music can sound in a controlled environment.

I also recommend that studio recording engineers get out and do some live shows. It’s amazing how much quicker you can become in getting sounds when dealing with the constraints of live performance. I also recommend recording your shows and making a habit of listening to the tracks regularly to identify what was great and what needs work.

I use a small portable recorder for two track desk mix recording and a computer for multitrack recording, when logistically possible. Remixing multitracks of an artist you have worked with a lot can be great fun as well as an excellent learning process.

b) Ear Training and Critical Listening

There are lots of ear training guides and suggestions out there but they all have the same goal, for you to identify frequencies or frequency bands, phase problems, comb filters and other frequency and time dependent anomalies. Listening to music, operating a 1/3 octave analyser and seeing the results on an analysis system is a very solid way to learn. It’s important to understand that it is your brain that is doing the analysis and interpretation and hearing acuity is only part of the skill. Critical listening is a much more extensive set of skills that requires many hours of listening to music in an super attentive and enhanced manner.

As an example there is a technique I use when teaching that you can try for yourself. Take a song that you know really well and try this test. Play the intro to your song for 15 seconds and listen hard. Stop the track and write down the answers to the following questions.

a) What individual instruments were played? (“drums” doesn’t cut it, name each individual drum, cymbal or other percussion instrument, include everything).

b) What bar does the lead vocal come in on?

c) What are the harmonic components supplied by which instruments?

d) What key is the song in?

e) What are the solo instrumental lines? Played by which instruments?

f) What is the meter and tempo?

We are only scratching the surface here but you get the idea. Listen to lots of different music including classics like Bach and Mozart, rock from the Stones to U2 and Jazz from Miles Davis to Snarky Puppy using this same exercise.

Check the links section at the end of this post. It includes ideas for ear training musicians and mix engineers, it is all useful and applicable to your work.

c) Familiarity with common sound equipment

Something else that should be self evident but is often not the case. In this age of increasingly complex digital mixing consoles it is more necessary than ever for an engineer to have a good grasp of at least one major desk platform and it’s even better if they know two or three different platforms. The ease of use of each platform is a matter of familiarity and opinion. In my opinion an engineer should have a good working knowledge of one or two of the following desk brands, Digico, Yamaha, Avid, Allen & Heath, Midas (in no particular order). Speed of operation, routing, bus mixing, processing and monitoring are all important things you need to be familiar with. How to use snapshots (scenes) and the importance of snapshot templates and safing various parameters. Most manufacturers have good quality off-line software that serves well for preparing show files and understanding how the desk works. These are free programs that can save you time, headaches and maybe your reputation the next time you step up to one of these desks. Let’s not forget outboard processing gear, patching and troubleshooting. YouTube is a great resource for finding helpful videos from basic to advanced on a wide variety of audio gear including the most common desks.

d) System Tuning

In my opinion, the mixing console is where you develop your mix and exercise your art. But this is not the end of the chain and someone has to setup and then tune the speaker system to work for the mix, the artist and the room. It’s not that easy, especially when you have multiple zones, fills, delays, distributed subs and all the bits and pieces that are part and parcel of modern show systems. Most people use FFT based analyzers to do this job, Smaart is probably the best known example but there are several others.

Some engineers rely on the production company to supply a measurement rig, others carry their own rig. Either way the engineer needs a good working knowledge of how to use the software and, more importantly, how to understand and interpret the measurements to get good results on a regular basis. On larger tours this is usually the responsibility of the FOH audio system tech. For the many smaller tours that do not carry speaker rigs or use the house rig, the mix engineer may not have the luxury of a system engineer and either accepts the house rig as it is or carries out the system measurements and adjustments themself.

No matter how much you analyze a rig it is always necessary to check the overall tuning by ear. The best way is by using two or three commercially recorded tracks that you know really well. Check for overall frequency response and walk around the venue to confirm the coverage is what you want. I keep a folder of "Soundcheck" tracks that I use regularly.

e) Networking Audio Equipment

Not only does an engineer need a working knowledge of computer networks they need to be able to adapt to or modify an existing network on the fly. They may need to accommodate items that they carry with them or incorporate rented elements into a house network. Furthermore, the advent of audio over IP hardware and protocols necessitates delving into network configuration. I suggest you take at least Level 1 Dante training, it helps you understand what the important parameters of Audio over IP are.

f) Troubleshooting

This is where knowledge of signal flow and routing is so important. There are many devices and connections in the audio chain. Being able to figure out quickly where a problem has most likely occurred and how to fix it is incredibly helpful. This takes a mental aptitude for following blocks and chains of signals as well as a lot of experience. Tough to train for, it is mostly learned “on the job”. Having people who can mentor you on this topic is really a boon. A multimeter, clip leads, a pluggable audio source and a small powered speaker or headphones will help you find maybe 80% of signal problems. The other 20% is probably what telephone technicians call a “misop”, often an air gap (unplugged connection point) or a console mistake (mute on, gate on, input unassigned, incorrect routing .. this could be a much longer list).

g) Personal Communications and Networking

How well you get along with other people is key in our industry. Many mixers and engineers will rate this skill as 50% of everything we need to do the job well. We are not rugged, amazingly talented and supremely competent individuals on our own little cloud islands. We work in teams and have to get along 24 hours a day with all our colleagues. Even if you are not a particularly social person it really helps if everyone else thinks you are OK and easy to get along with. That means practicing good social habits, behaving in a very reasonable manner and supporting the others. “Please”, “thank you”, “good morning”, “well done” are great phrases to use in a close knit group environment. The best thing you can do is to treat everyone else in the same way you would like to be treated. It is extremely important to understand these ideas when dealing with artists and musicians, their skills and challenges are a lot different from yours.

Personal referrals are the way that most people get work in our industry. That means you have to be connected, have a profile and be very easy to reach. It also means that you need to get to know as many people as possible on your journey. Other mixers, production people, production managers, promoter reps, stage managers, backline guys, music directors and musicians are all contacts who might be the one to speak up for you because you worked with them somewhere and you were a “good guy”. Carry business cards with all your contact information and hand them out, old fashioned but effective and you don’t need an internet connection! Develop an on-line presence and keep it freshly updated with what you have done recently. Contact people regularly to catch up, it doesn’t all have to be about whether there is work for you, just being friendly counts for a lot.

h) Preparation

This is a very important part of the live sound mix engineers job and is often underappreciated. Build your show files ahead of time. Even if you got good stage plots and input lists from the advance there are almost always changes so leave a few empty slots in your show file to allow for “Oh by the way we added another guitar!” kinds of situations. If you can have the stage patched, lines tested, monitors checked and equalised correctly and the main PA system tuned and ready to go, before the musicians show up, it is much easier to adjust balances and sounds to their liking and get a good grip on the house mix. If you are not ready then it rapidly becomes a flail.

If the artists have their own mix engineer(s) then request their show file ahead of time, install it in the desk and double check the assignments, input and output, so that on site you can plug and go with a good chance that everything is working correctly. It saves time and impresses the heck out of the visiting mixer.

i) Mentorship

Many think of mentorship as a long term relationship with a very old and wise person that knows everything there is to know about the industry. I think that this is an unrealistic and very limited view of what mentorship can be.

i. Mentorship is a two way thing, you can be a mentor to someone else and have another person mentor you.

ii. It doesn’t have to be a long term relationship. One tour leg is plenty of time to learn a lot from someone on your crew who has skills and knowledge that will help you.

iii. At the same time you can pass on your skills and knowledge to someone else who is eager to learn. It feels really good to “pay it forward”.

If you have an area where you need help or want to learn more you need to identify someone who has a lot of expertise in that area and ask them to help you. Most people will want to help and you can sweeten that by being friendly, helpful and offering to assist them in their tasks if that is what it takes.

Likewise if you find someone on your team who needs bringing along it makes the most sense to help them. Be friendly, offer clear explanations of your knowledge and skills and give them the opportunity to practice what you preach.

Summary

Looking back, it is amazing what breadth of knowledge and skills are required to be good at live sound mixing/engineering. None of us are experts on all of these topics, most mixers have an extensive knowledge and skill set in a few areas and are underdeveloped in others. You need to learn from the strengths of as many experienced people as possible.

Get Educated

I strongly recommend that young engineers get some kind of formal training in audio basics and live sound mixing. Beware the “recording school mentality” of institutions that offer recording courses and free recording software. You don’t need to learn every possible shortcut in Protools if live sound is your passion. You need time and instruction on micing up bands, using live consoles, mixing FOH and monitors, setting up PA systems, solving problems and learning how to get along in the industry. If you are researching courses ask lots of questions, especially the ratio of classroom to practical instruction time and how the practical instruction is organised with what equipment.

Courses on specific topics are great, for example, Rational Acoustics, the Smaart Analysis company, has hands on courses and an extensive series of YouTube videos. Likewise Digico, Allen & Heath and Avid. Self education is very important and should be a continuing journey throughout your career.

Get Experience

When you are starting out if you can get casual work at a local Sound Company, local theatre, church or night club you need to do it. You also need to be extremely professional right off the bat. Treat musicians and artists well, be friendly and conduct yourself in a happy frame of mind at all times, even when the day is rapidly turning to ****.

No matter what chaos happens during the day, when it’s show time then it has to be all systems go, and if something isn’t working then you have to find a way to get around the problem.

Develop a Professional Attitude

We are all different people with widely varying personalities. Some are happy-go-lucky, some are intense and some are permanently grumpy. Nevertheless when you are working you need to bring a positive, easy going and personable attitude to the gig.

That’s what I call a professional attitude. Understand that you can’t be grumpy, miserable and behave like an a**hole. You won’t last long and, to be honest, if you hate the gig that much, why are you doing it? It’s a bit of behavioural training that you need to do for yourself; once you get used to always having that professional demeanour it will last you your whole career. The corollary to this is if you are in a gig that is truly distasteful then bail, find a replacement, make it easy for the client but get out before it poisons your whole attitude.

A personal anecdote

Here’s a personal anecdote about a tour I did many years ago where the show day turned into a “rescue the show” operation.

We were touring in Spain with local production, the crew were great and hard working, we were carting around a ground stack PA and a large Yamaha analogue desk.

We did a show in Madrid at one of those large clubs that has an early evening show followed by a late nite disco, which is common in Europe. After our show there was maybe an hour to turn the venue which meant we had to strike our gear in a real hurry and start out immediately after for a long overnight drive to the south coast.

The next morning, we gave the crew a couple of hours to load in and setup, then the LD and I headed for the venue to check on their progress. At the venue they let me know that there was a problem, they had left the audio desk behind in Madrid in their hurry to load out and get on the road. They had already phoned around to locate a local rental but a large Yamaha analogue desk was hard to find and the in-town sound company was a big competitor and unwilling to be helpful. First off I gave the crew chief very specific instructions which were to be passed on to all the crew, “No matter what, don’t tell the band or the artist”. After thinking for a minute he understood that this was our problem and that however we solved it I didn’t want the band to worry about it or to get involved.

Eventually they located a local studio with a 32 input analogue desk that we could use.

I took a scalpel to the input list, eliminated all stereo channels, reduced the FX inputs to two and after getting all the critical components into the patch I had about 6 channels left for the many alternate instruments that the band played in different but not every song. Going from around 52 inputs to 32 was going to involve repatching channels between songs which is exactly what I did. I took the set list and made notes on patch changes for every song. We did a soundcheck, had supper and then the show. During the show the LD, stationed next to me, was thoroughly amused by the patch/repatch episode between every song, but we got through the gig with a happy audience and band.

After the show I checked in with the guitar player who was MD for the band, asking how it went for them. He thought it was a great show and to this day they never knew the amount of panic and hard work that it took to make it through.

Every day is a chance to learn something new!

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Useful Links

Acoustics & Engineering

https://audiouniversityonline.com/audio-basics-how-sound-works/

https://circuitdigest.com/article/understanding-the-fundamentals-of-digital-audio

https://www.allaboutcircuits.com/technical-articles/introduction-audio-electronics-sound-microphones-speakers-amplifiers/

Computer Networking

https://www.geeksforgeeks.org/basics-computer-networking/

https://www.educative.io/blog/computer-networking-101

Musical Instruments

https://lambdageeks.com/how-musical-instruments-produce-sound/