Selective Hearing? Have you tuned your ears in or are you tuned out?

Have you noticed that if you put your cell phone up to the ear that you don't use, it doesn't sound right. That's because your mind has trained your ear to use the right filters to compensate for the sound that your cell phone puts out.
It doesn't take that long but that is what is happening. If you are an audio engineer, you need to tune your ears.

Tools:
There are tools to help you do that. One of those tools is a good set of headphones. the reason you use headphones is because it takes the room out of the equation.

The next thing you need is something that will give you the tones or frequencies of interest. For live sound your ears need to recognize ⅓ octave frequency bands. So a tone generator or a CD with those frequencies on it is a must. Once your ears can recognize these frequencies it will give you the ability to find offending frequencies a lot easier then using an EQUALIZER you can take them out if need be. This is essential when you are dialing in monitors.

The next tool would be the ability to dissect a Mix or understand song structure.
Take a song and listen to it and try to map its structure, i.e. chorus, verse 1, chorus, verse 2, bridge, lead solo, verse 3, chorus, so on

Next find the instruments played in each segment.

Then map where they are placed in the mix (extreme left or extreme right, or does it move back and forth) map it in clock degrees. 12:00 being center 7:00 extreme left and 5:00 extreme right this is the part of the mix that bring movement.

Level - what loudness is everything at in the mix. Is the snare drum as loud as the lead vocal? It helps if you use the Lead Vocal as a reference. Map everything in relation to the lead vocal. Pay attention to what happens when the lead vocal drops out. Does another instrument take over?

Texture - or EQ how does that instrument sound. Is it natural sounding or does it sound beyond what the natural instrument is capable of sounding like. Is it deep or thin sounding? This is important because this will help determine genre. i.e. most songs use the same instruments (drums, guitar, bass, vocal) so what is the difference between a country song and a blues song in the way it songs and how we instantly recognize these things

Next on each instrument try to determine if there is an effect (reverb, delay, chorus,) if you don't know what these are you need to find out. this part is important because this determines the depth. Something that has lots of reverb sounds farther away. That is how we determine distance. The more reverb it has we perceive it as being farther away. For example background vocals should be at the same level as the lead vocal but should have more reverb on them to make them seem farther back than the lead vocal.

Last - What is the identifying sound of a Country, Hard Rock, Blues, or Jazz song. Once you can put your finger on these things you will be an excellent audio engineer.

problems with Mackie SWA1801 Subwoofer and the Fix

I recently had to check the speakers on a pair of Mackie SWA1801 subs for blown speakers. Once I got the front cover off (many bolts) to get access to the speakers I found that the wire that supplies juice to the blue LED was resting on the speaker. I checked the speaker, no noise from pushing in on speaker. The problem was the wire vibrating against the speaker in use. I strapped the wire back, problem solved. I'm not sure if the SWA1501's have the same problem, but if anyone thinks they have a blown speaker they should check the wire first.

The rest of the cabinet was put together quite well considering the cost of these speakers. I checked the amplifier side of the speaker and once I got the amplifier module off, I found everything to be in good order. This is a sealed cabinet and Mackie did a good of sealing. The hole for the wires from the amp module going into the cabinet was sealed with silicone. The only complaint I would have from these subs is the amplifier doesn't have a good enough damping factor to control that 18" speaker. The result is a muddy bottom end.

Sub Woofers - Why the 180° polarity switch?

There is a reason why that switch is there on sub-woofers. Off topic a little, if you have a cell phone and you are looking for a bluetooth headset you will run into a process called "noise cancellation". What is that and what does that have tot do with subs? The answer is everything.

When 2 sources of sound send audio into a room hitting the same space it causes cancellation. That is the principle behind the noise cancelation devices. This is not a problem for your main speakers if your system is running stereo. But it is a big problem for subs. Usually subs are wired to run mono, and the wavelengths of the sub frequencies are huge. For example a 20Hz signal has a wavelength of 56.2664 ft. How big is your platform? is it 40' or 60' across? A 30Hz signal has a wavelength of 37.5109 ft. So do the subs placed 40' apart cause cancellation? Yes big time. The solution change the polarity on one of the subs. That way when the one sub is on the outward movement the other sub is on the inward movement. You will notice a big change in the sub frequencies.

Concerts - Do you go anymore?

When was the last time you went to a concert? I stopped going... why? The sound in the venue was terrible.

The last one I went to was Eric Clapton when he toured with a 40 piece orchestra. I thought that having an orchestra with the band would be great. Surely they would have good sound. Well they didn't. I believe the touring company was Showco and I usually don't to concerts where Showco does sound because they use their own boxes loaded with JBL components. (not a good sound very harsh on high end). I don't know who mixed the show but we didn't hear the orchestra until they got to the unplugged portion of the show. Its funny to see an orchestra playing their hearts out and not hearing a peep from them. There are very few concerts that I have gone to where the sound was great. With the new line array systems out there now, I think I will have to check it out.

Active or Passive for Main Speakers? Part Two

If you have a system that you are going to add to or just update some components, your existing speakers for example, the passive speakers are your best bet. Unless you are looking to really upgrade to the next level. I am working with a church right now that has a passive speaker system and are upgrading to a line array.
If they go ahead with the new line array system (they are active) some of the components of their existing system will be sold (excess amps and crossovers etc). They have a 6 speaker Turbo Sound 2 way system (main cluster), the subs are a dual 15" and single 18" cabs on each side of the platform, all powered by QSC amplifiers. They have a 80' x 80' sanctuary with a balcony in back (see pic).
We are proposing an ISP Technologies Active Line Array system consisting of either 6 HDL4210 boxes (12° vertical) and 2 XMAX212 active dual 12" horn loaded subs, or 2 Reference Line 4215 boxes and 2 XMAX212 Subs. We are conducting a listening demo during the week before Thanksgiving. This system will greatly improve the music quality of their system. All the other components of their system will stay. I will post pics of the demo and comments from the pastor.

Active or Passive for Main Speakers? Part One

I have had a lot of questions lately about whether to go active or passive in the choice for main speakers. While active is great, it does deserve some caveats. If you choose an active system make sure that you order one extra of every model you have in your system. The reason; if you have a problem with any of your speakers it will have to sent somewhere to get repaired. Having an extra allows you to keep the integrity of your system while the component is being repaired.
So which is better?
It all depends on your application. If you have a small venue (less that 1000 seats) active is a good choice.

The criteria being:
• You have good access to the speakers (make adjustments)
• Any component of your system can be easily changed out (if there is a problem)

The advantages:
• Speaker amps are tuned for the speaker and the enclosure
• 0 loss of signal from amp to speaker
• An amplifier for each speaker (bi-amped or tri-amped)
• Built in crossover and electronics
• More efficient (power)

The disadvantages:
• If there is a problem, it will be difficult to get the problem resolved. (you will have to remove your speaker from the system for awhile) no spare, hole in system
• Adjustments to levels only done at speaker location (i.e. 20' off the ground)