UK Gospel awards Sound system hire

In the last few weeks we did the sound for the UK Gospel awards, which was held at the London Hilton Metropol Hotel.  Around 20 acts performed, including Ron Kenoly.
On front of house we used Martin W8C wavefront.  Monitors were ASS Spektra SPM12 and SPM15s, and mixing was on a Mackie Onyx 3280.

5 Video screens, including a central LED screen provided an interesting backdrop to the stage.  The event went well, despite several no-shows during the awards presentations!

For PA Hire, please check out our website, at www.soundtruth.co.uk

Green PA Hire

Environmental concerns have risen in profile in the last few years, and few companies or individuals can choose to ignore these completely.  I've read people suggesting that hiring the most efficient speakers (i.e. those that produce the most sound for a given power input) is the most environmentally friendly approach.  This suggestion does not however take into account that efficient boxes (often point source) can sometimes be the heaviest and largest.  Transportation is surely a massive factor if green concerns are paramount.
Line array system can offer a greener option as less equipment is typically required to cover the same number of people.  Of course a lot depends on the exact set-up in question - from an environmental perceptive, less is more, but from a rock'n'roll perspective, MORE is more!

Void Stasys3 Point souce speaker - fantastic sound, but heavy

A 10KW PA system will only use an average of around 2000W, with odd peaks above this.  This of course depends on how hard the system is driven.  But moving this equipment on a 200 mile round trip does have an environmental impact.
The solution, at least in some instances, may be to use firms local to the event where possible.

If you're looking to hire a line array or point source speaker system, have a look at my website, www.soundtruth.co.uk

Sound System for Sean Lock

If you're looking to hire a sound system for a corporate event or a band, have a look at my website here.

A few days ago I did the sound for the comedian Sean Lock at a corporate awards function, which took place at the Park Plaza Riverbank Hotel in London.  A Sennheiser EW300 series microphone was set up, but most of the talking was done from the lectern, equipped with a pair of Audio Technica ES915 mics. Front of house speaker system consisted of 6 HK Audio IL12.1 speakers flown in three way clusters.  An additional 2 boxes where flown over the dance floor.  6 HK Audio Elias subs were positioned under the stage, in order to preserve sight lines.  Front of house mixing was accomplished with a Soundcraft GB4 desk, with Mackie digital outboard.

Sean Lock on stage

The positioning of the subs made for a very clean looking stage area, also with no speaker stands in sight as all the mid / high tops where flown from a 12m truss, parallel with the front of the stage.  There was a certain amount of power alley noticeable during the DJ set, but this was a price worth paying to hide all the subs.

In order to provide maximum gain before feedback, only one of the Audio Technica ES915's was used, the other serving as a hot spare.

Sean Lock proved to be a very entertaining host, although the official photographer might disagree, being the butt of several jokes!

How to use a compressor

This article is taken from my website, which may be of interest if you're looking for PA Hire.

Compression is an essential tool in modern sound engineering. Most commercial recordings will have compression on just about every instrument. In the world of live sound, many amateurs do not correctly understand the best use for compression.

Compression should be used in the first instance to help achieve a sound without harsh or unexpected peaks that cut though and ‘grate’ on ones ears. The human ear is actually more sensitive to these mid-range frequencies. The main culprit here are vocals. This is because vocals have a lot of mid-range frequency content, and because singers (even good singers) often unintentionally vary the distance from their mouth to the microphone, effectively giving their voice even greater dynamic range.

Adding compression limits the dynamic range, evens out the small variation in microphone position, and provides a smoother sound for the audience. You can achieve a similar effect by ‘riding’ the fader on the vocals and listening, but it’s pretty hard work, and the singer can catch you out.

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suggested settings for vocal compression:

• Ratio 3.5:1
• Adjust threshold so the gain reduction is showing 3-9 dB during singing.
• Adjust the limiter so it cuts in only on the peaks, if at all.

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suggested settings for tie clip mic:

• Ratio 8:1
• Adjust threshold so the gain reduction is showing 3dB or less during talking
• Adjust the limiter so it cuts in when the gain reduction gets to 9dB (un-clip the mic and move it closer to your mouth to do this)

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suggested settings for bass guitar, or electric guitar:

• Ratio 2.5:1
• Adjust threshold so the gain reduction is showing 3-6dB during playing

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suggested settings for acoustic guitar:

• Ratio 4:1
• Adjust threshold so the gain reduction is showing 3-6dB during playing
• Set the limiter to cut in when the gain reduction gets to 9dB

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It’s important to remember that using a compressor on an insert will affect the signal sent to the monitors as well. Too much vocal compression may be annoying for an experienced vocalist who expects the monitor to get louder as they approach the mic. Although, in the case of an experienced vocalist, less compression (lower ratio) is normally needed to reign in the sound!

Use of the attack and release controls can change the way the compression behaves. It takes a while to become familiar with the effect of the controls, and with what works and what doesn’t. In most cases, a fairly fast attack and a medium or slow release is the way to go. We would suggest you leave your compressor set on auto if it has this feature, and if not, leave the controls at 12 o’clock!!

Compressors can be used for a variety of other applications, even across a whole mix. This can have un predictable effects – in general it’s best to restrict the use of compression to a few key channels, unless you really know what you’re doing!

How to Prevent Feedback in a PA System

The article below is reproduced from my website, you can find it here:- www.soundtruth.co.uk/soundbasics.shtml

We get asked this all the time, and we're afraid that there is no very short answer (other than “turn it down!”). However, there are steps that can be taken to greatly reduce the risk of feedback. Reduce the risk almost to zero in some circumstances.

• Reduce on stage volumes where possible - then you can reduce monitor gain and hence reduce the possibility of feedback. Prime culprits here are on stage bass guitar amps, and drums... drums being more of a challange to 'turn down'!
• Encourage vocalist to sing really close up to the mic. Not all singers are used to, or like this technique, but from a monitor engineers point of view it works best! A good singer can still pull the mic away a bit for louder syables, words or sections. This tip is especially hand for vocalists that are asking for more in the monitors than you can give them without feedback.
• Eliminate simple causes of feedback – for example a guitar or bass left plugged in, turned up and on a stand. Inexperienced musicians are prone to doing this and need to be educated!
• Make sure your FOH speakers are positioned not to bleed into the microphones.
• Be aware of the pickup pattern of your microphones, and use this to your advantage. Most mics are cardiod, and so are pretty directional. Make sure they are not pointing at monitors or front of house speakers.
• Don’t put unnecessary mics such as the drum overhead into the monitor system.
• Don't use more mics on stage than nessasary. Every time you double the number of mics on stage, you reduce the gain before feedback by 3dB (the system will start to feed back at a perceieved volume about 30% lower than before).
• Use good quality microphones. If you’ve ever used a really cheap mic, you will know how prone they are to feedback and handling noise. Having said this, many people won't find much difference between an £80 microphone and a £350 microphone. Just avoid the cheapo £20 mics and you should be OK.

Shure SM58 Mic, a good industry standard vocal microphone

• Use good quality monitor speakers. Many venues try to save money and buy cheap monitors for the band – this is a shortcut to feedback problems, and a poor stage sound.
• Use good quality FOH speakers. Poor quality FOH speakers can also give feedback problems due to comb filtering and un-even frequency response.
• Hearing loop systems can cause feedback, especially into electric guitar pickups. Solve the problem by removing the guitar from the loop mix, or reducing the loop mix level.
• Follow a standard sound-check procedure (for an example, read running a soundcheck) and make sure to do the FACE / FLAT HAND / CUPPED HAND test, with all the mics ON, both in the monitors and FOH.
• Listen to the feedback and identify the frequency. This can be done with skill – or when an audience is not there, you can ‘sweep’ the mid band EQ and ‘find’ the offending frequency. Cut the frequency by 3dB and the feedback problem will reduce. More cut can be used in some cases, but will of course start to influence the sound of the mic. Low frequency feedback (for example from a tie clip mic), can be reduced by cutting the bass. LF feedback from a kick drum or toms is normally countered using a gate.
• Use a graphic EQ on either the FOH or relevant monitor mix to cut the offending frequency. Some engineers ‘ring out’ a monitor or FOH rig prior to a show. This can result in up to 6dB more gain before feedback. However, the monitors can end up sounding rather dull, as one normally ends up with quite a bit of upper mid-range cut on the EQ (The bands on a normal EQ are not really narrow enough, and end up cutting more frequencies than are required).
• Use a feedback destroyer. In some ways a last resort… the cheaper f/b destroyers such as Behringer can have problems with noise levels. Sabine make better but more expensive models. They use very fine notch filters to cut feedback frequencies and need the system to be ‘rung out’ prior to use in order to work at their best. They should give about another 6dB gain before feedback, without the side effects of graphic EQ or channel EQ.

World's largest photo album- PA System

Last week we supplied a PA System for the Worlds largest photo album.  The record was atempted by Photobox at the Old Truman Brewery in London's Brick Lane.

Worlds largest photo album

Sound coverage was needed for background music, and various anouncments for up to 300 people.  We supplied and installed a pair of Yamaha MSR400 powered speakers, together with a Soundraft E6 mixer and a Sennheiser EW100 series hand held radio microphone.
The photo's on display were superb, and many of them were taken by amature photographers around the UK. The subject was World travel.

The Yamaha speakers were partly conceled behind the pillars

What is loud? Why do I need to know about dB SPL?

Perception of loudness is a complicated subject. Every person will perceive loudness differently, as everyone’s ears are different. In fact, everyone’s ears have a slightly different frequency response.

This is why, in sound engineering circles, there is a need to quantify sound pressure levels to define what is loud, and what is quiet. Or perhaps that should be; what is too loud and what is too quiet. The unit of measurement is the dB SPL (decibel). There are also more accurate measurements of loudness called phons, and subjective loudness, called sones, but these are rarely used and are outside the scope of this course!

For convenience we normally measure dB SPL from the mix position, but it can be useful to measure from other areas such as the front row and the stage.

For those new to dB SPL here is an idea of how different sounds compare in level:-

Recording studio	30dB SPL
Conversational speech	60dB SPL
Noisy office	80dB SPL
Church concert (contempory worship)	95dB SPL
Loud rock concert, front row	120dB SPL
Threshold of pain, average young person	130dB SPL
Concord take-off from runway side	140dB SPL
.357 Magnum handgun, (peak impulse)	165dB SPL
Under a Saturn 5 Rocket on take-off!	194dB SPL

This article was taken from my web site, you can read more about PA Hire and dB SPL here.