Thursday, 19 July 2012

Mixing 101 - Making Gains - Part 2 of Many

Last week I discussed how to set-up a mixing desk properly but left you in the lurch on the 3rd step which is setting the gain on each channel. This subject deserves an entire post on its own due to the influence it will have on how well things will turn out.
Firstly, there is a lot of quite complex physics and maths related to this topic which I have purposefully left out. Hopefully my crude metaphors will explain the topic a little more easily than a physics or maths class.

Lets first take a look at what gain actually is.
For starters, the level of the signal that comes out of a microphone is tiny. It is so small that you can't really do anything useful with it at all.
In order for us to be able to do some useful things (like EQ and effects), we need to make the signal 'bigger' or 'louder' than what a microphone can produce.
We do this with something that is built into every single mixing desk called a pre-amplifier or pre-amp.
The gain knob simply controls how much we amplify the microphone signal so that the mixing desk can do useful things with the signal. Think of it as just like a tap that can open up or reduce the flow of water going into a sink (our mixing desk). If the tap is too high, then the water comes in faster than it can go down the plughole and the sink overflows. If the tap is too low, then the water drains away before any collects in the sink.

If the signal coming into a mixing desk is too weak, then we have to turn the faders up really high to get it loud enough, this results in noise or hiss because we are also turning up all of the unwanted signal that gets generated inside the mixing desk by all the electronics.
If the signal  coming into a mixing desk is too strong, then it will begin to hit the operating limits of the electronic components in the mixing desk and the sound quality will degrade with distortion. (the sink will overflow).

What we need is every single signal coming into the mixing desk to be like Goldilocks porridge... just right.

The gain knob can be used to increase the 'volume' of a weak signal, or decrease the 'volume' of a strong signal so that each instrument is the exact same level.

We call this 'ideal' volume Zero (technically this is called 0dBu but don't worry about what the U means too much) and it is usually marked about 3/4 of the way up the meter scale. Anything below Zero has a minus in front of it, and everything above Zero has a plus in front of it. The 'space' above Zero is called Headroom and means just what it sounds like it means....

If 50 people get on a bus, then they will be all different heights, so they build buses with a bit more space above everyone's heads so that the tallest people do not have to duck down. Headroom in a mixing desk works the same way as a bus roof and generally the more headroom a desk has, the more expensive it will be. Just like a bus with 2 meters of headroom would be expensive. However if occasional you carry very tall people, that extra Headroom can be very handy.

Lots of headroom is a good thing and is worth paying a premium for.
Cheap desks will only have +6dB to +9dB (I have left off the U to avoid explaining some complicated stuff) above zero, while expensive desks could have +18dB to +24dB (or even more) headroom.
All that additional headroom gives you much more control and will contribute directly to the sound quality of the end result.

You can see in the photo of the Allen and Heath Zed mixing desk above, this desk has +16dB of headroom above zero which makes it pretty good for a small desk. Take a look at your own mixing desk and see what it goes to before it peaks out (note sometimes desks go a little bit higher than the meters show just in case).

Gain also goes in the other direction (minus) and how a desk behaves at the other end of the spectrum is just as important as what it does with very strong signals. This is because gain is directly related to noise.
Every single audio device generates noise. Noise consists of hiss and is not unlike the sound that cassette tapes used to make (showing my age now). We measure the amount of noise a device makes relative to its distance from our 'ideal' Goldilocks level. This is called the noise floor and we want the noise floor to be as far away from 0dB as we can get it. The closer the noise floor is to 0dB the more hiss we will hear in our sound system. When you are buying audio equipment, always make sure you look up its noise floor (again, it is worth paying a premium in this area). This information is usually buried in the technical specs at the back of the user manual, but is actually more important than most of the headline features that you see on the glossy brochures.

To give you a bit of a feel for what is good and bad:

  • A cassette tape has a noise floor of around -65dB. That means in the quiet bits when there is nothing recorded, the volume of the noise will be -65dB. We all know how bad the hiss was on cassette tapes, so if you buy audio equipment with a noise floor around this level it will have as much 'hiss' as a cassette tape.
  • The noise floor on a cheap mixing desk from an un-named manufacturer beginning with the letter B is -85dB. Obviously better than tape, but don't forget that sound systems are generally much louder than home stereo's which means the noise will also be louder. Equipment from this manufacturer is notoriously noisy.
  • The noise floor on a typical home stereo is between -80dB and -95dB (for a good one). Obviously CD based systems sound much better than cassette tapes, so this gives you a good reference but often you can hear the hiss in your home stereo.
  • The noise floor on our  Allen and Heath Zed reference desk is -100dB. This is what I would recommend as an excellent noise floor for a mixing desk without getting too expensive, at this level, when you turn up the volume to full and have no music playing, the hiss will be barely noticeable.
Now onto the fun stuff...

Once you have completed the line check I described last week, the next step is to set the gain on each channel.

Get your helper to play each instrument and check each microphone once again, it is imperative they do this at performance levels. The classic bad example of this is saying "Check 1,2" into the microphone at a whisper, then peaking out all your channels later on when someone actually sings into the microphone at performance levels.

To set the gain, press the PFL button on the channel you are setting and slowly turn up the gain knob until the signal on the meter sits nicely around zero and occasionaly peaks to +3dB for only the loudest parts. (If you have a realluy good desk and are a competent sound engineer, you make like to make 0dB the average and have your peaks go considerably over 0dB).

If your gain knob is turned all the way down and the signal is still way over 0dB then press the PAD button on that channel which will reduce the signal by 20dB, you can now start turning up the gain again until you get the signal just right.

When you have done this for all of your channels you have now completed setting up your mixing desk and you are ready to move onto the next step which is the actual sound check.

Thursday, 12 July 2012

Mixing 101 - Line Check - Part 1 of Many

This week we start a new series of posts that will concentrate on mixing desk fundamentals.
I'll be using the Allen and Heath Zed series of desks as a reference for this series, mainly because they are probably the best quality small format analog mixer on the market right now and also because they have all of the most important functions we will be talking about in this series and none of the unimportant ones that often clutter desks up.

Lets say you have just un-wrapped a brand new mixing desk and are about to use it for the very first time.
Where do you start?
Its tempting to just dive in and plug stuff in, and rather than be a killjoy who tells you to read the manual from A to Z whilst 'familiarising yourself with your new mixing desk's layout", I'm actually going to suggest its not actually such a bad idea.

But here are a few suggestions to make the process less painful..
Before you plug in anything, zero all the faders, slide them all the way down to nothing so that no audio signals can come out of the desk.
Next find the gain or trim knobs (usually right at the top of each channel strip) and spin them anti-clockwise all the way down to nothing.

The rest of the channel strip knobs also need to be set to zero, where zero is will depend on what the knobs function is. It is important NOT to set them all fully anti-clockwise.

The following knobs are zero'd in the full anti-clockwise position:
- Anything with AUX written on it
- FX sends

The following knobs are zero'd when in the 12 oclock position (pointing straight up):
- EQ  (usually labeled HF, HM, LF etc)

If your desk has a phantom power switch (usually labeled with '48v') on each channel, make sure it is off for now.

Now you are ready to begin, I'll take you through the process of getting ready to use your desk. You go through this same process every time you use it, for every gig, no matter how big or small. The same process should be used when playing on a Thursday night at the Cossie Club or at an 80,000 seat stadium show.

Step 1 - With all the faders and knobs zero'd, plug in all your instruments into the channels you want. Set them up in a layout that is easy and quick to access and try and use the same layout everytime you play. The 'unwritten' soundguy standard is to put drums first, bass, then guitars, then other instruments and vocals last. Plug your PA or speakers into the desk outputs.

Step 2 - Line check. This step is just to make sure that everything is plugged into the right channels. One person taps each mic or makes a noise on the line while the other person checks the desk. Most desks have a PFL button that helps with this process. While a helper taps the kick drum mic, press the kick drum PFL button on the desk and slowly turn up the gain / trim knob until you start to see the signal on the signal meter. If you don't see anything, check the microphone does not need phantom power (turn on the phantom button if needed). If there is still nothing, you have something plugged incorrectly, or you have a faulty cable or microphone. Get this sorted before moving on. Work your way through all of the rest of the channels until everything is where it should be.
Note: You haven't turned up any faders yet, and no sound has come out of the speakers.

Step 3 - Setting the gain. This is the most important step, in fact it is so important I am going to dedicate an entire post to it next week. Getting the gain right is the single most important thing you can do to ensure whatever you mix sounds great so it is worth spending a bit of time understanding what this misunderstood little red knob actuall does.

Thursday, 5 July 2012

The Value of Live Music.

A deviation from technical subjects today to discuss a topic near and dear to me.
What is the value of live music?
How much should your band charge?

The answer to this question is that "It depends".
One of the problems with live music is that from a musicians perspective, its is a pretty fun thing to do.
Getting up on stage is an exhilertating and satisfying experience and that has a nasty side effect in that it often clouds a musicians judgement on what is a wise thing to do.

When you have a fun job and you get offered an opportunity to do it, of course you want to accept every opportunity that comes along because you don't really see it as a job. The problem is that many of these opportunities are to perform for free and by agreeing to perform for free you are basically shouting out at the top of your voice that your performance is not worth anything.

Think of it this way....
As you walk into a McDonalds, someone hands you a voucher for a free Big Mac. Mmmm nom nom nom you think.
So you go to the counter and get your free Big Mac.
Just as you are walking away from the counter, your Big Mac slips out of your hand and smashes to bits on the floor.
Oh crap you think, but how upset are you really? Chances are you will just shrug your shoulders and say "Oh well, it was free anyway".

Now if you paid for that same Big Mac, you are going to be a whole lot more upset about it because you made the concious decision to part with some money in order to get it. Really think about that for a second and about how you may have used the words "Oh well it was free anyway" at some point in the past.

They are the same Big Mac and they cost exactly the same to make, however, we don't value the free one at all, while we place a higher value on the one we paid for. The free one is nice to have and we certainly enjoy it. But if we didn't have it or we lost it we wouldn't really care at all. When you pay for something, you enjoy it more and generally the more you pay for something the more you tend to associate it with quality. Think of wine and how much people pay for a 'good' bottle of wine.
Its just wine, but for some reason, some people think that a bottle that costs $500 tastes better than a bottle that costs $20.
Really the only thing that is different is the price. The wine still came from grapes on vines and probably cost around the same to produce. Its just they probably made a LOT of the $20 bottle and not very much of the $500 bottle.
Still, wine 'people' will swear black and blue that the $500 bottle tastes better.
It doesn't taste better, it just tastes different.

Unfortunately for us music works the same way.
If you play for free, your performance will not be valued, you will not be valued and you are effectively telling people that your product is worthless.

So how much should you charge?
Well again, it depends.

If you are a huge international star and a promotor is selling tickets for your show, then your value is quite high for obvious reasons. But how much is a band playing in a pub worth?

If a band just turns up and plays 3 hours of covers, does no promotion for the event, doesn't bring any followers and doesn't encourage people to spend money at the bar, then the value of that band is quite low. Its simple economics, if a bar has to pay you $1000 but the bar only makes an extra $500 by having you there, then you are overcharging.

However, if you promote to 5000 facebook fans, you print posters, you generate a huge buzz about your gig and bring an army of followers to the pub that all spend a small fortune at the bar, then you will quickly find the demand for your band goes through the roof and your ability to charge a high rate goes up accordingly.
The pub will also not care if you play covers, originals or the theme songs to childrens programs because they are making significantly more money than what they would if you were not there.
This same model works for any type of event but pubs are the easiest and most common example to work with.

Musicians often complain about being poor or only being able to charge a couple of hundred dollars for their whole band to perform.
This probably means you are doing something wrong.

If a pub says to you "We only pay bands $300" then you are doing something wrong.
If a pub says to you "How much do you charge" then you are doing something right.
If your answer is $2000 for a 3 hour show at a pub, then you are doing something really right!

In order to maximise how much you can charge, my advise is to:
- sort out your marketing and promotion and make sure it is top notch
- generate a following and a huge buzz around every performance.
- create a reason for people to come to your shows (new songs, giveaways)
- Actively pursue a large facebook following
- Make sure you have a top quality website with all your news and gig info
- Name a drink after your band and get the bar to do a special on it then get everyone to buy one.
- Book gigs in blocks, give pubs a discount for booking you for 5 gigs in advance over the next 6 months.
- Actively promote the pub during your gigs, actively promote the bar and any drinks specials.
- Actively promote your next performance at the same bar, say when you will be back.
- Actively tell everyone your band name at least 5 times during the show so it sticks and they remember.
- Make sure your audience has an awesome time!!! (don't just play for your own satisfaction)

Thursday, 28 June 2012

Tightness 101

Tightness is a term that is often used to describe how well a band plays together.
Its a word that is often bandied about a lot without a lot of thought for what it actually means let alone how a band that is not tight could strive to achieve it.

I've listened to a lot of live bands over the years, some who I would call incredibly tight and others... well not so much. I think I have the answer and an 'easy' way to make your band sound 'tighter'.
Tightness is usually restricted to a few specific generes. You don't call a big jazz band 'Tight' because actually looseness is part of what makes a big band so awesome.
Tightness is usually associated with RnB, all forms of Rock, Funk and to a lesser extent blues.

But what makes a band tight?
After listening to a few old live recordings of tight bands and then some not so tight bands, it all points to one place, the rhythm section.
Drums and Bass are the key to tightness, guitars and keyboards can be all over the place (in terms of timing) but the band can still be classed as tight.
More specifically, it comes down to one part of the band, drums and the bass guitar.
Tight bands have the following thing in common, the bass guitar and the kick drum are almost indestinguishable. In fact, they sound like one instrument playing together. The kick drum providing the punch and the bass guitar providing the tone. All you need to do to make your band sound tight is get your drummer to kick his kick perfectly in sync with the notes of the bass guitar (apart from any frilly bits).
The drummer can play anything they like over the top of this, the Snare and Hi Hats can be way in front or behind the beat, but so long as the kick is in sync with the bass, the band will sound tight.
This can be harder than it sounds. The drummer and the bass player need to listen to each other very carefully and anticipate what the other is going to do. Good rhythm sections can do this without any thought at all. An average rhythm section can also do it, it just takes loads and loads of practice.

Here is an example of what I'd class as a tight band (listen to the kick and the bass interact):

Conversely, here is a band that is not tight (its not hard to be better than these guys).

Next time your band is practicing or doing a gig, listen to how the kick interacts with the bass guitar.
Are they playing the same thing, or are they each kind of doing their own thing?
Try making some simple changes and really focus on the kick and bass guitar and see what happens to the overall feel.

Thursday, 21 June 2012

Getting rid of Noise

Last week I got asked to explain the difference between a balanced and unbalanced audio connection. It's surprising how few musicians understand how a balanced connection works and therefore what the pros and cons of balanced vs unbalanced connections are. Most people think it has to do with the quality of the cable, which is completely wrong.

The knowledge can save you a world of pain when it comes to resolving unwanted hum and noise in both your instrument and PA system. 

An unbalanced signal is the most simple and commonly encountered audio connection as it is found on most electronic instruments including guitars. Guitar leads are un-balanced cables and have two wires in them. The black wire is called ground and it has absolutely nothing on it. It is simply connected to the earth (yes the actual dirt) and acts as a reference point of zero volts. 

The red wire has the actual signal on it represented by a positive and negative voltage relative to the ground wire.

Think of ground as being "sea level" and the signal as being the height of a mountain we are trying to measure. We can compare the heights of any two mountains in the world because they are all measured relative to their height above the sea. 

Audio works the same way, but one big problem is that our sea level isn't exactly the same everywhere you go. In some rural areas power companies transmit power through the ground using one wire above the ground and using the ground itself as the other wire. This (along with a whole host of other reasons) causes the voltage measured between two points in the earth to be different. It can even vary from one side of a venue to the other which for a musician is a real pain in the butt.

If you have two power points in a venue and half your gear is plugged into one and the other half plugged into the other and those power points have a different earth point then you get a different ground voltage (sea level) for different equipment in the same PA system. This comes through the PA as an 'Earth Hum' and is literally the sound of the earth humming. It is like putting a stethoscope on the planet. 

To compound the problem, humans are addicted to wireless things. TV, Radio, Microwave Ovens, Satellites, and Cellphones all emit radio and electromagnetic radiation. When these waves hit metal, they generate a tiny voltage. If the metal is long and thin then it acts like an antenna and guess what we musicians like to use a lot of that is made of metal and is long and thin?  

Ok, insert your 'long and thin' jokes here, but the actual answer is, guitar leads. 

Guitar leads are basically perfect antennas. All that electromagnetic radiation that is flying around the place crashes into your guitar leads and induces a tiny voltage on both the red and the black wire which you hear as noise in your amp. The net result is that the longer and poorer quality your un-balanced cables are, the more noise they will pick up and the worse the noise will get. When you use lots of un-balanced cables together in your PA system then the noise all adds together and you end up with a bit of a mess of hums, hiss, buzzes and in the worst possible scenario - Breeze FM coming through your equipment.

So what is the alternative?
The answer is to used balanced cables wherever you can and here is why.
Balanced audio cables have 3 wires instead of two.
The shield wire is a special braided mesh that surrounds the enclosed wires, it also is connected to the ground so acts as our "Sea Level".
The red wire carries the signal, just like in our unbalanced cable.
The white wire carries an exact copy of the signal but 'flipped'. If the red wire has a positive 5 volt signal on it, then the white wire has a negative 5 volts on it (referenced to sea level). Its like digging a  hole in the ground that perfectly matches the contours of the mountain that we are measuring. 

Now, when all that electromagnetic noise hits our cable, it induces the same voltage in both the red and the white wires at the same time.

At the other end of the wire, our mixing desk cleverly flips the signal on the white wire back the other way and then adds it to the red wire. Think of it as pouring clay into the hole we have dug and then superimposing the clay mould on our original mountain.

Now the original red and white signals match each other and add together to make a stronger copy of the original signal, however, the noise on the white wire is flipped the opposite way to the noise on the red wire and perfectly cancels it out resulting in absolutely nothing but a perfect copy of the original signal.
Using this method, I have transmitted audio over several kilometres without any noise, hums or buzzes.

Its pretty clever, and also the reason why you should use balanced cables and equipment wherever possible to minimise noise.

This is why, on stage we use DI (Direct Injection) boxes on anything that has an unbalanced connection. Keyboards, Acoustic Guitars, Samplers, CD players or even iPods etc are the usual suspects. If you want the best sound possible then you need to convert an un-balanced signal into a balanced signal as quickly as possible and using the shortest possible un-balanced cables you can.
Get rid of those long guitar leads and if you use powered speakers, then connect them to your mixing desk using XLR cables not jack cables.

Whenever possible, look for equipment with balanced audio outputs as opposed to unbalanced outputs. Professional equipment usually comes with balanced connectors while cheaper equipment may not offer that option. Also note that sometimes professional equipment (most often keyboards), may offer both balanced and unbalanced connections on the same jack. This is called a TRS output and is a jack cable with 3 rings instead of 2. You can then use a cheap TRS to XLR converter to convert the jack into a mic lead and therefore avoid using DI boxes on this equipment but you may need to look at your equipment user manual to find out if it has balanced connectors.

Thursday, 14 June 2012

To Hear or not to Hear, that is the question?

Every musician at some point in their lives will perform on a stage where they either can't hear themselves or the rest of the band. When this happens it immediately sucks the life out of your enthusiasm to play, what should be something that is incredibly fun and rewarding immediately becomes frustrating and irritating.

A musicians monitors can make the difference between a good performance or an amazing performance. If there is a separate sound engineer mixing monitors, their job is more important to the integrity of your performance than the front of house sound engineer. They have the hardest job on the stage as they have to keep the stage volume as low as possible, while also trying to make sure the artists can hear.  

There are two common types of artist monitors, each has advantages and compromises, neither is perfect.

Foldback, Wedges, Monitors or to some just foot-rests, are the most common solution to the problem of hearing on stage. They are easy to deploy and are fairly flexible. 

The primary problem with foldback wedges is noise. Wedges add an enormous amount of noise to an already noisy stage. By the time your drummer pounds their cymbals, bass player thrashes their 1000 watt amp and the guitarists point their 200 watt quads at their knees, the noise levels bouncing around on stage can be insane. Far louder than the front row of the mosh pit. When you add a row of monitors along the front, it often turns into a noise war with each wanting more volume from something to compensate for the 'more me' everyone else wants. 

While this scenario usually generates a lot of on stage energy it is very bad for two important reasons. 

The most obvious is ear damage. Usually not discovered until you crawl into bed at 4am with the all too familiar and distinctive rinnnnnnnnnng in your ears. Ears are a musicians most important asset and its ironic few musicians pay the real consideration to ear health they should. Often the level of deafness a musician achieves is joked about or indicates some sort of right of passage. Personally I find that blatant stupidity.

The second problem that is less often thought about is quality. 

All that noise bouncing around the stage gets into vocal and drum mics and results in a muddy background din through the PA. This makes you sound like a school band rehearsing in a garage. The sound engineer is going to have no control because if they need more vocals in the mix what they really get when they turn up the vocals is more noise. 

So in summary, wedges usually make for great energy but average sound unless you are very careful about controlling the onstage volume level.

The more modern solution to the problem of noise is In Ear Monitors or IEMs. 

IEMs consist of high quality earphones that go in your ears and provide your own personal mix via a wired or wireless signal from the mixing desk. 

The advantages of IEMs are fairly obvious, you can run the overall level at a much quieter volume while hearing everything crystal clear. 
Often IEMs are so good that it feels like your are in a recording studio. The stage noise can be so low that the quality of the mix you and your audience hear can be like listening to a CD. Herein lies the problem with IEMs. When you plug those earbuds in, it's easy to feel like you are in your own little bubble and go into dreamland, completely forgetting the audience is there and completely forgetting you are on stage to perform, not to self indulge in your own awesomeness. 

This can sometimes result in a disconnected performance where the audience does not feel like you are really all there. 
There are some solutions to these problems, the most common and damaging to your ears is to use one IEM and one wedge. This is supposed to give you the clarity of IEMs with the energy of wedges but it has one serious drawback. It is likely to damage your IEM ear significantly more than if you were to just use wedges set to 11. 

Due to an unfortunate trick your brain plays on you with one earphone in and one off, you think it is much quieter than it really is and turn up the volume on your IEMs to damaging levels without even knowing you are doing damage. 

Try this for yourself by plugging in your iPod with only one earphone. Then turn it up to the loudest volume you think is safe to listen at long term. Now put in the other earbud. You will be shocked how loud it is. In fact I would be surprised if you can bare it for more than 2 or 3 seconds. Remember the volume hasn't changed, its simply a trick in your brain. If you only take one thing away from this article it should be to never, ever, ever just use one earphone.


The better and easier alternative is to use an audience microphone. 

Put up a high quality consensor mic and point it out to the audience, then add it to the mix in your IEMs but not to the PA mix. This will allow you to get all the benefits of IEMs while still being able to hear the enery of the audience. 

The latest trend and more expensive option is to purchase IEM systems that include built in ambience microphones. These allow you to adjust the ambient noise level right from your belt pack. These systems are amazing but are also very spendy as they are targeted at the high end. 

I personally recommend IEMs and also recommend investing in some high quality custom moulded earbuds. I'll talk about that more another day but when using IEMs I always recommend keeping in mind that you that as amazing as it sounds in your ears, there is still an audience out there in the dark that need to be entertained.

Thursday, 7 June 2012

The difference between Loud and Good.

Loud is good right?

Not really, there is Good and there is Loud and here is why.

I first noticed the difference between Loud and Good about 10 years ago when I was mixing sound for a country music show that was mostly comprised of older audience members.
The first band was really good (not that I'm a huge country fan) and I happened to glance down at the dB meter (measures volume), it was touching on 95dB (thats pretty damn loud) and here were a group of blue rinse oldies sitting in the front row happy as can be.

Latter the same night another band did a country rock number and the guitars were awful. Even though I pulled the volume right down to not much more than 80dB, I still got several complaints from a couple of oldies that it was too 'loud' and several people at the front had their fingers in their ears.

So how is it that people perceive loudness then?
Here we have a situation where somone finds music as loud as a jackhammer perfectly ok while the same person finds music no louder than the road noise inside a car to be so loud they need to put their fingers in their ears.

My conclusion after all these years is that it all comes down to quality, and I'm not just talking about quality of musicianship. The quality of the PA system, musicians and venue acoustics all play their part in determining what volume sounds good to people.
The higher the quality of all these factors, the greater volume your audience will tollerate.

It is therefore my belief that if someone tells you to turn it down, they are not really asking you to turn it down, what that really means is one of these things..
  • They don't like your music.
  • The PA is not big enough for the gig (and is distorting)
  • The venue accostics are rubbish
  • You aren't that good.
Death metal is a great and probably slightly more extreme example.
I've heard some amazing metal bands in my time, and some of them at what would normally be excessive volumes, but if the band is tight and the guitars have good tone, then you can tollerate high volume (SPL is the technical term - Sound Pressure Level) before your ears start to fatigue and tell your brain that it is too loud.
I have also heard some very bad metal bands. Sometimes they are tight as hell and have a great stage show, but are let down by the guitars having a horrible tone. Here is a tip for death metal bands, if your guitars sound like a swarm of buzzing bees inside a tumble drier, turn down your treble knob. It will make the world of difference to your bands sound and you will be able to play much louder before your audience's ears start to bleed.

Guitarists and drummers should also be aware that if you have been playing hard rock or metal for a number of years, your ears have probably lost a good deal of their high frequency response. Usually the first frequencies to go are 2Khz to 4Khz which just happen to be the frequencies that normal humans are most sensitive to. If you are constantly asking people to repeat themselves, but can otherwise hear fine, its a good indicator your ears are damaged in this range. It is the frequency range where consonants are generated and if you can't hear consonants then you can sometimes struggle to hear what people are saying, while still being able to hear the sound of a pin hitting the floor perfectly fine (a much higher frequency).
What this means is that while your guitar sounds more awesome than an awesome thing to you, the sound is cutting through the eardrums of your audience like a knife through butter. If in doubt, ask someone with normal hearing for an honest opinion of how your instrument sounds, even better, ask a sound engineer (they tend to look after their ears a bit better than musicians and will give you an honest opinion).

Ear fatigue can be a major problem at gigs for musicians.
Your ears are pretty clever things, and if something is too loud your brain starts to block out that frequency. If you have your guitar set too loud while you play, then your ears will progressively start to shut down during the gig. The next thing you know you are nudging the volume up a bit more after every song. Thats when the stage starts to turn into a battle zone as your bass player then turns up his amp because he can't hear any more. Then the vocalists asks for more monitors and it turns into a vicious circle. By the end of the gig, its so loud on stage your ears are just about bleeding and your sound is... well... shit.

To avoid this, set your volume on your amp at sound check and mark it on your amp with tape or a white marker. Then, don't touch it. If you can't hear yourself, then ask the things that are causing you to not hear to turn down instead of you turning up. This will avoid ear fatigue and result in a far superior sound out in the audience, where it really matters.

Thursday, 31 May 2012

How to make your band sound clear, tight and not 'muddy'.

One of the most important things about playing in a band is understanding how your instrument fits in the mix.
As a sound engineer, one of the most common problems I hear in live bands is unclear vocals and either a muddy sound or a piercing sound that makes you want to put your fingers in your ears even when its not that loud..
This is actually a really easy problem to fix, but first you need to understand why it happens.
Take a look at this great chart...
Musical Frequency Chart

It shows all the instruments and what frequencies the instrument generates.
A band that sounds tight and 'phat' will make sure that the instruments have as little as possible overlap in terms of the frequencies they generate. This means that the bass guitar is not making the same frequencies as the rhythm guitar, and the lead guitarist isn't overpowering the vocalist.

That leads me onto the number 1 cause of unclear vocals....
If you look at the chart the first thing you notice is the electric guitars operate in almost exactly the same frequency range as vocals. This is both good and bad. Its bad if your guitars are too loud when your vocalist is singing because the guitar will make the words sound unclear.
However, its really good when the vocalist stops singing and its time to rip out a mammoth guitar solo because you can get away with turning the guitar WAY up, and I mean WAY up.

If you are playing lead guitar, make sure you always have a boost footswitch for your solos, and you really can get away with having quite a big difference between normal and solo volumes.
Think of it like this... when you are playing during the verses, keep your guitar level right down and just fill in the gaps around the vocalist, during this part you need to be complementing the vocals not competing with them.
Stick to one string stuff and play in a different register to the vocals. If the vocals are singing high, then play low notes and if the vocals are low play high notes.

Then when the vocals stop and its time to solo, think of the guitar as the vocalist during the solo. Make the guitar sing, play it loud and strong then pull way back again when the vocals kick in.

While we are on the subject of guitars, keep an eye on your bass and treble, make sure the bass notes on your guitar don't interfere with the highest bass guitar notes, and make sure your treble notes stay well clear of the range where humans are most sensitive (2k to 3k). A guitar is a mid range instrument, don't try and generate all the frequencies of the spectrum just because you can.

On to vocals, and its important to remember that humans can generate quite low frequencies even when singing higher notes. Percussive sounds like 'P' and 'T' words can also interfere with the bass guitar and make your whole band sound muddy. Turn down the bass control on the vocal channels to improve the clarity of the whole bands sound.
If your mixing desk has a High Pass Filter (button or a knob on more expensive desks), this is the greatest invention in this history of sound and you should use it. Turn on the high pass filter on every single channel except the bass guitar and kick drum and you will see an amazing improvement in clarity.

Friday, 25 May 2012

Why cupping a mic looks cool but thats about it..

Cupping is for musical dicks
You see it on hundreds of music videos (mostly in Hip Hop) and as a result you see it occuring more and more on live stages of all genres. The lead vocalist with their hand wrapped around the base of the microphone ball. Wow they look so cool!!.
But mic cupping, is bad for you and here is why...

Despite what most people think, there are two sides to a microphone. Most think that it just the front part where you stick your mouth or point at the instrument that is the important part. However the back of the mic plays just as much a role in both the way the mic sounds and also how the mic responds to its environment.

Most vocal mics have what is called a 'cardoid' pattern, that means they mostly respond to sound from the front of the mic and 'reject' sound from the back of the mic. Thats why you can turn a mic up loud and point the bottom of it straight into a speaker and you won't get feedback. However flip it around and point the mic directly at the speaker and you will get a load of feedback.

When you cup a mic, you change the response pattern of the mic from cardoid (only from the front) to Omni-directional.
That means the mic picks up sound relatively equally from all directions, not just where you point it. The immediate thing you will notice is that a cupped mic feeds back much more easily than an open mic.

You can try this for yourself, just turn on a mic and turn it up fairly loud, then cup it by putting your whole hand around the ball of the mic and watch the feedback go crazy.

Cupping is also going to destroy the sound because the microphone is going to pickup sound from everything else around the stage as well as the vocalist this is what makes it sound 'muffled'. Basically, if you like the sound of a cupped mic, you may as well just ask your sound engineer to turn up the 'Shit' knob on the mixing desk.

A cupped mic will sound quieter than an un-cupped mic but of course you will not be able to turn it up because it will feedback at between 1/2 to 3/4 the volume of an un-cupped mic (depends on the mic model).
One other thing to watch out for is tape or anything else that might get stuck to a mic at some point, if you tape up a broken mic, it will also cause the same effect. Sometimes you can use this to your advantage, for example if you are mic'ing up a percussion instrument where there is sound coming from all around, I will sometimes use an SM57 with tape over the bottom grill to get a more full sound from inside a drum.

You can also use this phenomenon as a good visual indicator of how a mic's response pattern will be. Generally microphones with big rear grills will be highly directional, while microphones with no or a very tiny rear grill will be more omni-directional. Watch out because this is counter intuitive to what you would expect to happen.

So there you go, next time you see some rockstar prancing around the stage with their hands wrapped around the ball of the mic, tell them why it might look cool but is actually seriously uncool for their sound.

Friday, 18 May 2012

The importance of cable to your sound

The cables between your instrument, pedals and amp are part of your instrument. A good guitar lead costs $40 to $80. Most music shops stock rubbish leads that will colour your tone. Here is a good way of testing the quality of your cables.... Plug one end of the cable into an amp then turn the volume way up. Now rattle the cable on a hard floor. A good cable will be totally silent when you do that, the more rubbish the cable is the more noise you will hear in your amp. This is called cable microphonics and means a rubbish cable is basically acting as a microphone. This is bad if you want the best sound possible.

Also, for guitarists, avoid wireless guitars wherever possible. Some of the best tone comes from the electrical interaction between your instruments pickups and your amplifiers preamp. If you use wireless then there is no interaction between the two so the tone will often sound quite 'flat'.

Use the highest quality cables you can afford, put your name on them and guard them with your life.

The same goes for your PA system. Cables are your PA.

A good mic lead costs $30 or more and good speaker leads well over a hundred bucks each. Your system will only sound as good as the poorest quality cable in your whole system so all your cables have to be good quality in order to reap the benefits. Good quality cables and microphones are more important to the overall sound quality than the speakers, amplifiers and mixing desk you choose.

Cables usually comprise 20% or more of the cost of a good PA system. Throw away the cables that come as part of a PA package, they are usually the cheapest quality the manufacturer can possibly find.
Also, coiling cables properly maintains the sound quality. If you wrap them around your elbow then the braid inside will quickly start to disintegrate which will destroy the cables shielding and cause your cable to become microphonic. Ask anyone who works in the sound or lighting industry how to coil your cables to make them last forever.