Audio / Buying Guide

Live Sound 101: Sound System Design and Setup for a Live Band

         

If you have been tasked with setting up a sound system for a small band that wishes to reach an audience of 300 to 500 people, there are various elements, both strategic and technological, to consider. Audio tech people have never had such a broad range of sound reinforcement equipment and techniques at their disposal. The choices of technology and products available can be overwhelming, so let’s talk about some of the options.

Speaker Selection

Your choice of speakers should be based on coverage requirements and the size of the venue. There are some things to consider regarding the shape of the room and how the speakers will interact with boundaries, such as the walls, the ceiling, and the floor.

You want to get the best speakers your budget will allow. Start by figuring out what you can afford and then determine what sounds best to you within that price range. Always listen to the speakers before buying, as not all of them are made equal. When choosing a speaker, you’ll want to consult the specification sheet, which should be readily available from most reputable manufacturers. The most important specs to know are the frequency response, SPL output, and dispersion. If you are using passive speakers, then you’ll need to know the wattage and impedance (ohms resistance).

A full-range speaker with a frequency response of 60 Hz to 18 kHz may be fine for many genres of music, such as country, folk, or folk-rock, where the kick drum and bass don’t need additional punch. For rock, metal, pop, hip hop, EDM, etc., you will want a subwoofer. A subwoofer extends the frequency response down to 45 Hz or lower and will allow the full-range speakers additional headroom and increased output.  

Frequency Spectrum for Full Range Tops and Subwoofer
 

The sound pressure level of a speaker will determine how loud a speaker is at a given distance (typically 1 meter). Most spec sheets will show Peak and Continuous outputs. The peak is how loud the speaker is on loud transients, while continuous output is the average loudness. This is a good indication of how the speaker performs, dynamically. Sound pressure levels (SPL) will attenuate by 6 dB with the doubling of the distance. If a speaker were capable of 135 dB at 1m, then 2m would have an SPL of 129 dB. By doubling the distance to 4m, the speaker would output 123 dB and so on. Another consideration is that doubling up on the speakers will result in a +3 dB increase. If a speaker has a peak output of 135, by adding another speaker the output would increase to 138 dB.

Sound Pressure Level to Decibels Distance
 

Dispersion is the way the sound is projected horizontally and vertically from the speaker. This is incredibly useful for determining the placement of speakers, as you can direct the sound away from boundaries, such as walls and ceilings. For instance, a speaker with a 60-degree horizontal dispersion might work well for a narrow room, while adding an additional speaker could increase the dispersion to 120. The goal is to offer coverage to the entire audience, while directing the sound off the walls. Many speakers are designed to couple by utilizing a trapezoidal enclosure, versus a square or rectangular enclosure. The trapezoidal design allows for easy placement of the speakers, as they can be placed together in tight-knit group or array, which allows for coupling with reduced interference between speakers.

The vertical dispersion will determine how high the full-range tops will need to be to provide proper sound coverage for the audience. There are many ways to configure a system, in terms of height and whether ground-stacking, speaker stands, scaffolding, or trussing should be implemented as a way to get the speaker high enough to offer extended coverage. The higher the speaker, the farther the sound will travel. If it is too high, there will be a loss of impact in the front. Not high enough may result in the sound being uncomfortably loud for the front row.

Horizontal Dispersion Vertical Dispersion

For our purposes, I suggest setting the tops at shoulder to head level, about 5 to 6 feet from the floor. If you are utilizing subwoofers, you might try ground-stacking the tops on top of the subs. Many speakers offer pole mounts for use with speaker stands. This is the simplest way to get proper height, especially if you don’t have multiple subs to create a ground stack. At the very least, you want your high-frequency driver above the heads of the people in the audience.


Ground Stack
 

Active versus Passive

There are pros and cons to both active and passive speaker designs. Active speakers are the easiest to deploy with built-in amplifiers that are matched to the speaker components (woofers, mid-range, and tweeters—typically compression drivers). They also feature crossovers, which isolate and route frequency ranges to each component, and built-in limiters for protecting the drivers. A three-way active speaker will have two or more built-in crossovers, which isolate the high, mid, and low frequencies. The advantage of active speakers is the ease of setup and operation. They only require a line level input and you won’t have to use separate amplifiers to power them.

Passive speakers require amplification, speaker cables, and may require an outboard crossover and other signal processing. Some passive speakers will utilize an internal crossover network, which functions much like the active speakers. Other speakers are designed to be bi-amped or tri-amped, which can be a benefit, as this allows greater control over the speaker components, but also requires a separate amplifier for each component of the speaker. If you decide to go with a passive speaker design, you’ll need to look at the specification sheet provided by the manufacturer to determine the correct amplifier(s).

Active Speaker Passive Speaker

The input range of a speaker is typically given in continuous, program, and peak wattage measurements. You will most likely see the continuous output and either program or peak. The general rule is a doubling of the continuous results in program, while doubling the program will give the peak performance. For instance, a speaker with a continuous input of 1400 watts will offer a program of 2800 watts and a peak of 5600 watts. The larger the amplifier, the more headroom will be available. Do you really need to match 5600 watts to this speaker? Most professionals will say no. A good formula is to aim for 1.5 x the continuous input. A 1400 watt input x 1.5 is 2100 watts and should be the bare minimum for this speaker. A safer bet is to match the speaker to the program output of 2800 watts.

Another consideration is the impedance or ohms resistance for the speaker. You will need to consult the amplifier specifications to determine how much power an amplifier is able to produce at a given impedance. Most manufacturers will boast the highest output of both channels at the lowest resistance. When matching your amplifier to your speaker, it’s important to consider the ohms rating and wattage. For instance, an amplifier that is rated at 4000 watts (2000 watts per channel) at 2 ohms will realistically deliver 1400 watts at 4 ohms and 850 watts at 8 ohms. We could certainly use this amp with our 1400-watt speaker, but at its continuous output rate, it doesn’t leave much headroom. Without headroom, it is entirely possible we could drive the amplifier into clipping and potentially damage the speakers.

Some amplifier manufacturers will indicate power draws as 1/8 power, 1/3 power, and full power. 1/8 power delivers the amplified signal below the built-in clip limiters, while 1/3 power will have the clip limiters occasionally flashing. Full power will have the limiters in constant activity. When engaging the clip limiters, you are actually rounding off the audio signal to prevent distortion, but the signal of the audio will be compromised. I prefer to run the amplifiers at 1/8 power, which will give plenty of headroom without squaring off the waveforms. You may also use a higher-rated amplifier at 1/8 power without fear of damaging your speakers. Remember, the quickest way to blow a speaker is to underpower it.

Subwoofers also come in active and passive options with the same pros and cons. There are many different designs that can offer pretty outstanding results. The best bang-for-the-buck I recommend is a Yorkville LS801P. It is a self-powered, single 18" tapped-horn design with a tremendous output, rivaling or surpassing most double 18" designs.

Yorkville LS801P Subwoofer
 

Depending on your setup and how many subs you have, you will have more consistent results by placing all the subs together. Placing two subs together will yield a 3 dB gain in SPL and they will couple without interference. A stereo sub configuration may create null points in the room where certain frequencies cancel each other out. Other tricks to maximize bass are to place the subs near a wall or corner, as each of the boundaries will reinforce the sound and help load the room. My favorite configuration is to center-cluster four subs together (2 wide x 2 tall).

Speaker Processors

Regardless of whether you are using active speakers or passive speakers with an amplifier, you should invest in a speaker processor. In my opinion, it is the most important piece of gear and will save you time, money, and headaches. A speaker processor combines a number of processors into a rackmount signal processor. You will find gain, EQ, delay, crossovers, and limiting for both input and output. A typical processor might have a stereo input and six outputs. The inputs will feature a 6- to 8-band parametric EQ and/or a graphic EQ, as well as a system delay. Each output on your processor will offer gain, a 4-band parametric EQ, a delay for time-aligning speaker components in a bi-amp or tri-amp application, or a full-range speaker and a subwoofer.

Signal Path for a Passive Sound System
 

You will also find digital crossovers featuring Bessel, Butterworth, and Linkwitz-Riley band-pass filters. Each crossover offers a high-frequency and low-frequency setting with selectable filter types. For tops, I typically set the HPF to 96 Hz on a 24 dB per octave Linkwitz-Riley filter and the LPF to off. For subs, I set the LPF to 96 Hz on a 24 dB per octave Link-Riley filter and the HPF to 30 Hz on a 48 dB Butterworth filter. The major focus is the crossover between the LPF of the sub and the HPF of the top. A 24-dB-per-octave Link-Riley filter keeps the frequency response flat where both the subwoofer and top are crossing over.

Note: A speaker processor delay is not a digital delay effect, as it is intended to literally delay a signal by a set amount and does not offer a “wet/dry” setting. If a manufacturer offers time delay settings for your speakers, you can use those to time align the tops and subs. The LS-801P has a 3 ms delay, so adjusting the tops to match the inherent delay of the subs will provide a coherent and phase-accurate wave front. If you don’t have the specs, you can invest in a measurement system like SMAART. If you have an iPhone or iPad, you can purchase the AudioTools app by Studio Six Digital, which can help you measure and calibrate your sound system.

Analog Mixers versus Digital Mixers

Analog mixers are the mainstay of any audio system, and range in price and features. There are some diehard analog enthusiasts who will not move to a digital mixing board, as they believe the analog components sound superior to digital. If you are mixing a live band, you will want some additional signal processors to shape the sound of each instrument. Most analog mixing consoles will offer a built-in four band parametric EQ, which helps balance the tonal sound and carves out space for each instrument in the mix. It is rare to find analog consoles with built-in dynamics available on every channel. Therefore, an all-analog setup will require several racks of gear to accommodate the additional signal processing, such as compression and gates for each channel.

Analog Mixer Digital Mixer

Another aspect to consider is the use of wedge monitors or stage monitors. These are speakers that are typically on the floor and angled up toward the performers, offering a dedicated mix, which allows the musicians to hear themselves on stage. Feedback can become a problem, so the use of graphic EQs will be needed to remove the frequencies that are feeding back. Add in additional signal processors like multi-effects, delays, and reverbs and you can see the analog setup may sound better, but will cost more money with the additional signal processing, plus there are additional racks, cabling, troubleshooting, and maintenance involved.

Digital mixers have made some considerable advances in recent years regarding the quality of the sound, and pricing that is comparable to many moderately priced analog consoles. Digital mixers offer the best solution for any touring band, with a large channel count and each channel packing four-band EQ, compression, and gating. Additionally, each output features graphic EQ for ringing out monitors. Many mixers feature internal effects with up to eight insert slots for use with internal sends. You can still use your favorite outboard gear, but the digital platform reduces the amount of gear substantially. Another benefit of the digital mixer is the wireless control options. Many mixers offer iOS and Android control apps.

BEHRINGER X32 Digital Mixing Console IOS APP
 

If the FOH position is in a less than desirable place, the engineer can move about the room to make informed adjustments based on the audience’s perspective. This also allows the engineer to tweak monitors from the stage, while standing next to the musicians. Many mixer platforms will allow multiple device setups in which band members may adjust their own mix in real time, allowing the FOH engineer to focus on the main mix. Other features now incorporated in the digital platform include spectral analysis and a real-time analyzer (RTA) for making adjustments to monitors or to the entire mix. However, I still recommend a dedicated speaker processor for tuning the sound system.

Stage Snakes and Stage Boxes

A stage box or multi-channel snake is highly beneficial for reducing clutter on the stage. Some larger stage setups use a splitter that splits the signal from all the sound sources on stage between FOH and monitors. Most mid-level bands typically don’t have a dedicated monitor engineer, so the FOH engineer will perform both main mixing and monitor duties. With an analog setup, you’d be working with a 16- to 24-channel audio snake with a cable run of 100+ feet. A drum kit may have 8 to 12 microphones set up to capture the sound, so a dedicated sub-snake allows for shorter mic-cable runs and a much cleaner stage setup.

Stage Sub-Snakes
 

Utilizing stage sub-snakes before going to the main stage snake will keep the cable clutter on stage to a minimum. Many digital mixers offer digital stage boxes that function like an analog stage snake, only instead of a 16- to 24-pair multi-channel cable, the digital snake will use a single CAT5 cable to connect to the mixer in the FOH position. This cuts down considerably on the weight and setup time of the entire system.

Digital Snake
 

Microphones

In order for musicians to be heard, microphones are used to capture vocals, guitar amplifiers, and drums. The mainstay of live music is the use of dynamic microphones. There are many microphone manufacturers, but the favorite of most clubs is still the Shure SM58 for vocals and SM57 for instruments. They have proven their value over time by sounding good and being incredibly rugged. They can literally take a beating and still function. If there is the budget and desire for wireless microphones, I personally recommend the Shure QLX-D series digital microphones. They offer clean, clear sound without any artifacts, and with a simple setup.

Shure QLX-D Series Digital Microphone
 

In-Ear Monitors

Many bands prefer to forgo the use of stage monitors and opt for in-ear-monitors (IEM). I’ve used the entry-level PSM300 Shure Personal Monitoring System for years and have had excellent results. With a digital mixer, the setup and operation is even simpler, resulting in very happy musicians who are able to set their own monitor mix—and without excessive stage volume.

In Conclusion

As you can see, there are many directions one can choose when setting up a sound system for your band or event: analog mixers versus digital mixers; passive speakers and subs versus active designs. Each has its pros and cons. The most important thing is to use your ears when making decisions. Always listen to speakers before purchasing and, if possible, demo speakers and subs together, especially if you are using different brands. I can’t recommend enough the importance of having a dedicated speaker processor for any system, regardless of size or budget.

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Please advice us on a qoat for the MUSIC upgrade of the following: 1x processor, 1 x set of drums, 2 x yamaha keyboads, 3 x Guitor, 6 x hybrid live speakers, 2 x sub hoovers, 3 x amplifiers, snake cables, 1 x 24 channel mixers, 24 mike stands, 24 mikes, 1 x vedio camera,  and 1 x stage monitor.

Unfortunately this is not the best channel in which to reciever quotes. Please see our B&H Governent, Educational & Corporate Sales Page to request a quote and find pertinate contact information.  

Hi I'm looking to expand my business into a live sound market. I've been a DJ for almost a decade and run a sound lighting rental business. I Want to start providing sound for larger events and provide set ups for bands. Dj and music playback have always been my thing so live music is a different monster I need to learn, I funn all EV EKX AND JBL PRX700 Series subs, tops ect. Speakers and quantity are not an issue. I'm looking for help as far as what I need in my rack besides DBX drive rack? Do guitars and drums require anything special or can anyone point me towards an article that can school me a little bit? Thanks 

Hi Josh -

The   dbx DriveRack PA2 Complete Loudspeaker Management System is an excellent addition to any PA setup, especially in large venues. I recommend considering an EQ as wel forbalandcing out instruments, vocals, and drumsl:

The black AD2055 Dual Mono Parametric Equalizer from Avalon Design features a Class A, discrete design with a minimum audio signal path for transparency when in use. The unit has two channels, each with 4 matching frequency bands, allowing for dual mono or stereo operation. Passive high and low bands are complimented by active parametric mid-range bands, with x10 frequency multiplier buttons for a broad range.

Class A, 100% discrete design

Minimum audio signal path

Dual mono operation

Transparent active and passive filter design

Headroom of 30 dB

Low noise of -94 dB

Fully balanced inputs and outputs

DC coupled, no transformers in audio path

Switched frequencies in high and low bands

Mid bands use x10 frequency for extended range

Bandwidth of -3 dB, 1 Hz to 450 kHz

Low distortion of less than 0.5% THD and IMD

All signal routing with sealed silver relays

Conductive plastic potentiometers for low noise

External 150W toroidal power supply

100% discrete power supplies for audio path

Long-lasting, stainless-steel hardware

Passive high and low bands plus 2 fully parametric mid bands

Hard-wire relay bypass for compressor in-out

Please contact us via e-mail if you have additional questions:  AskBH@BandH.com

Got a question:  I am researching the audio equipment needed for a new gymnasium. The volume/sq.ft. area of the gym is just a bit over 156,000.  There will be some sound dampening panels installed about half way up the walls to dampen the sound from just bouncing all over the place.  There will be bleachers on two sides with a seating capacity of about 1100.    My questions are:  1.  how many sub's should be aiming both directions towards the bleachers. 2. How many loudspeakers should be aiming both directions towards the bleachers. 3. Minimum wattage needs for number of speakers. 4. Number of amps needed for that wattage total (probably should be able to run at 2 or 4 ohms.) 5. Number of equalizers, mixer (probably about 6-8 ch.), sound processor (if needed).  6. CD / ipod dockable player.   Quality products are desired within reason and durability is a necessity.    If someone can give me some ideas with names of products and details relating to the speakers and amps, I would be appreciative.  I'm leaning towards QSC or Crown, JBL, Yamaha qualility products but open to others too.    Thanks for any expertise that you can provide.

Hi Phil -

Great questions all, Phil.  But your application and venue offer complexities of size, safety, service, installation, scale, acoustics and budget among other factors, that should be addressed by a versed professional integrator on site.  We would be happy to advise an integrator in terms of product choices, but offering products at this early stage might be counter-productive to your project without a qualified on- site survey.

Unfortunately for such a large job, we would not be able to make accurate recommendations or product suggestions off site. We would highly recommend bringing in a project professional who could inspect your location and make the appropriate recommendations per your design criteria.  While we cannot make a specific recommendation, one of our manufacturers does offer this type of service.

TOA Electronics is a premier manufacturer of audio and security products and does offer onsite design and installation. B&H would be more than happy to bid out the products required for your project.

Please contact Johnathan Allen at 845-729-3482 / jonathan_allen@toaelectronics.com.  He is an install professional that will be able to handle this type of  project for you.

 Please contact us via e-mail if you have additional questions:  AskBH@BandH.com

Got a question:  I am researching the audio equipment needed for a new gymnasium. The volume/sq.ft. area of the gym is just a bit over 156,000.  There will be some sound dampening panels installed about half way up the walls to dampen the sound from just bouncing all over the place.  There will be bleachers on two sides with a seating capacity of about 1100.    My questions are:  1.  how many sub's should be aiming both directions towards the bleachers. 2. How many loudspeakers should be aiming both directions towards the bleachers. 3. Minimum wattage needs for number of speakers. 4. Number of amps needed for that wattage total (probably should be able to run at 2 or 4 ohms.) 5. Number of equalizers, mixer (probably about 6-8 ch.), sound processor (if needed).  6. CD / ipod dockable player.   Quality products are desired within reason and durability is a necessity.    If someone can give me some ideas with names of products and details relating to the speakers and amps, I would be appreciative.  I'm leaning towards QSC or Crown, JBL, Yamaha qualility products but open to others too.    Thanks for any expertise that you can provide.

Hi Phil -

Great questions all, Phil.  But your application and venue offer complexities of size, safety, service, installation, scale, acoustics and budget among other factors, that should be addressed by a versed professional integrator on site.  We would be happy to advise an integrator in terms of product choices, but offering products at this early stage might be counter-productive to your project without a qualified on- site survey.

Unfortunately for such a large job, we would not be able to make accurate recommendations or product suggestions off site. We would highly recommend bringing in a project professional who could inspect your location and make the appropriate recommendations per your design criteria.  While we cannot make a specific recommendation, one of our manufacturers does offer this type of service.

TOA Electronics is a premier manufacturer of audio and security products and does offer onsite design and installation. B&H would be more than happy to bid out the products required for your project.

Please contact Johnathan Allen at 845-729-3482 / jonathan_allen@toaelectronics.com.  He is an install professional that will be able to handle this type of  project for you.

 Please contact us via e-mail if you have additional questions:  AskBH@BandH.com

So if i have powered speakers for p.a. And monitors, is it ok if i directly connect it to the processors since powered speakers has its own amplification?

Thanks in advance.

Hi Dennis -

Correct.  No muss - no fuss!

 Please contact us via e-mail if you have additional questions:  AskBH@BandH.com

What could I say? When I read this, it seems i return 20 years back. I'm sound engineer for 30 years, I worked with almost all pro gears analog and digital mixers but I never crossed brands which are mentionned in this article, instead of Shure, obviously.

In the pro market, we talk about Electro-Voice, L Acoustic, Meyer Sound, d&B, Soundcraft, Midas, Yamaha, BSS, AKG, Neumann and so on...

Talk about advertising for YOUR brands but don't present it as learning.

The guide to studio gears (microphone) from Jaime Traba was more interesting.

The technical details seemed accurate to me - the brand specific images were just stock photos to compliment the text. I'm sure they are all brands B&H carries, but they're not unknowns int eh pro audio world - You've surely worked with QSC amps, no? Their amplifiers are in touring racks and installs all over the world. And their K series stuff is some of the most rented audio gear in the states - you'd be hard pressed to find a rental house, at least in California, that doesn't carry QSC.

Behringer and Yorkville are lower-end brands, but MusicGroup (Behringer) controls a huge swath of both the install and live market - they own Midas, Turbosound, KlarkTecnik, Lake, T.C. Electronic, T.C. Helicon, Tannoy, among others, so they're not some fly by night company.

I suspect anyone who's shoppign for a Meyer rig knows all this already, and anyone who doesnt' know this stuff is unlikely to want or need a system of that caliber.

I'm also pretty sure B&H carries Yamaha and most if not all Harman brands (AKG, JBL, etc), so it's not like they crammed all the stuff they sell into one blog post.

Mr, did you notice the intention of this article? Was it for experienced engineers? Get a grip with your ego. Go outside, help out someone for free. Or write your own articles ment for professionals. Geez..