What is the best Projector for my Church?

Quantify whether you have the ability to do a rear projection system.

If you can do a rear projection system anything above 2000 lumens will work. Provided the space behind the projector is enclosed and ambient light can be controlled in that enclosure.

What to look for in a projector:

Minimum Lumens: Rear projection (2000)
Front projection (4500)

Contrast Ratio: >1000

Bulb: Arch type Bulb (not filament)

Minimum Bulb life: 2000 hours

Aspect Ratio: Both 4:3 and 16:9 (widescreen)

Resolution: 1280 x 720 (HD) other wise know as 720p (progressive)
1920 x 1080 other wise know as 1080i (interlaced)

If you can, try to find a projector that has sealed optics.

Panasonic has some new models that are liquid cooled and have sealed optics.
PT-D5500U
PT-DW7000U
PT-DW7700U

Thoughts on the new McCauley M Series Line Array

I recently when to a church service where they had a new McCauley M Series system installed. The configuration consisted of 7 x M-90 modules, 1 x M-120, 2 x MS1 and 1 x AC355 per side. The sanctuary is a 80' x 80' x 26' (WxDxH) with a balcony.

The 2 MS1 cabinets where flown in a separate array next to the main array. I noticed some interesting things (no mids) with lots of sizzle in the high end. They had an acoustic guitar player as well as an electric guitar and you couldn't hear either one. The vocals where not very clear either. Because the array had a vertical coverage of > 90 degrees of coverage, they had some slap back and early reflections in the seating area.

They didn't get as many amps as I thought they should because the boxes are 16 ohm cabinets so they could run up to 6 cabs per amp. This makes it extremely hard to adjust the gain level to the individual boxes to get a good balance in the array pattern (even SPL to seating areas) with that many boxes hooked to the same amp. I sat up in the balcony and it didn't sound full (week coverage) compared to the coverage of the M120s on the downfill (on the floor 3rd row from the front). Overall the best sound was on the floor from the downfill boxes but still no mids.

Believe it or not, this was way better than their old system.
This system would be classified as a 4 way system with the subs included. 2 way out of the M-90 and M120 boxes, third way MS1 box and 4th way out of the sub. The problem here is that the only boxes that are projecting to every seat is the 2 way box. We all know how 2 way boxes behave, they lack mids. The woof can't produce the lower mids and the tweet can't produce upper mids.
While line array systems are a better solution for larger venue (>500 seats), it doesn't guaranty a good system. The clarifiers to a good system are:

1. Keeping sound off the walls and ceiling (no early reflections into seating areas)
2. Full frequency to every seat in the venue.
3. even SPL to all seats in the venue.

The McCauley system installed at this church did not meet any of the above criteria. note: these specs need to be verifiable, not shown with a projected coverage modeler program.
(although the system was better than their old system I predict that they will not be happy with it for long)

The only only Line Array system that I know of that can meet the above criteria is the ISP HDL4210 and HDL4215 systems. They are true 4 way cabinets (5 way when you include the subs) but the important thing is that the each box truly projects full frequency to the seating areas. With 8 speakers per cabinet and dedicated speakers for the lower and upper mids there is no comparison. You have to hear these speakers.

Live Recording - analog, digital, with computer, harddisk style recorder, or mixer/recorder stand alone unit?

When you are ready to start "Live Recording" you will find in your research that you have a lot of options. Which one is the best? First you need to put together a couple of lists. One being the intended audience for the final product (target quality), and how to distribute it (internet, CD, DVD, DVD ROM, etc). Once you got that figured out you can start looking at what equipment and process it would take to do that type of recording. So lets look at an example:

We want to record the pastors message and put it on CD and put it up to the Web Site.
Target Quality: CD = 44KHz / 16 bit Internet = mp3 format

Now comes the fun, what do you use to record? You could use a Direct to CD recorder for example: Tascam CD-RW900/901 Standalone CD Recorders


But then you still have the internet version to deal with. For that its best to record direct to a computer. So for the above need the best solution would be to record to both at the same time. If you need to edit the material before you release it, the answer would be to skip the Tascam unit and record directly to computer and create 2 files when you are done editing. One for the CD distribution and one for the internet.

Next we will tackle: Live Music recording

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)

Ingredients to grow a church

1. The pastor better be a pastor, someone who loves people, a people person.
2. Grounded in the word
3. Have a great sound system

The last one may sound funny, but it is very, very true. If the congregation can't hear the word, or the vocal intelligibility is poor, the church will not grow. I have a good case in point. A baptist pastor called one day and asked if they could improve the vocal intelligibility of their system because the older members were having a hard time understanding the pastor's preaching. At that point they were running at about 150 people. We upgraded the system to a Left/Center/Right configuration and the worship (piano, organ, choir) sounded better, because of the stereo Left/Right . The vocal intelligibility was improved from the new upgraded center (cluster). All of a sudden, more musicians started to come and want to be involved and the congregation grew because the worship got better. The older folks enjoyed the service because for the first time they were not straining to understand the pastor. Now they are running two services and have approx. 1000 people. They have had to expand their facility and are thinking of adding a 3rd service. Its kind of the domino effect. The pastor now realizes the value of a good sound system.

I found some pastors that think its a nuisance to even have to buy a sound system. I once had a pastor ask me if he could get a system for $1,000.00 that would work for his congregation of 75 people in a church building that seats 250. I understand the lack of funds but what about the system working in the building. It is possible to put a system together for 75 people in a small venue like a large living room for about $1,000.00 but that would be maximum capacity. When you try to design a system you want to keep two figures in mind.

1. What is the smallest number of people you have in the congregation
2. What is the seating capacity of the building.

Once you have those figures, you add at least 20% to the second figure and that is what you want to build your system for. Here's why. When you reach 80% of the capacity of the building you are in now, you will look to expand or look for a new facility. When you get to your new facility or expansion, your system will be at the minimum level for that set-up so all you would have to do is add a couple of items or upgrade a couple of items to meet your new need.

I hope this makes sense. If you have any questions, drop me a line or two.

Using the right tool for the right job - microphones

How does a Microphone Hear?
The way a microphone responds to sound and the way we hear are vastly different. Understanding this difference will help you understand how to use microphones properly.

Human Perception of Sound
God has blessed most of us with an incredible mechanism to perceive sound We perceive a wide variety of sound characteristics such as:direction, loudness, pitch, etc. We can make mental choices of what we desire to listen to. This allows us to focus our hearing on what we choose to listen to.

Microphones Response to Sound
In contrast to the human hearing system, a microphone is a crude and simple device used to pick up sound vibrations. Actually a microphone only contains one faction of the human hearing mechanism, just a diaphragm which converts sound vibrations to electrical energy.

How is a microphone different?
It has no second "ear' to allow it to perceive direction
It has no brain, which allows it to choose what it wants to hear, and what it will focus upon.
The microphone will always give preference to whatever sound is the loudest at the microphone, even if it is not the sound wanted.

Basic Principles of Microphone Placement
Microphone placement for sound reinforcement through a live sound system differs from microphone placement for recording of for broadcast. The two situations will require separate approaches. We will concentrate on microphone technique for sound reinforcement.

What is the proper microphone placement?
Microphone placement can be anywhere from 2" to many feet. Depending on the source to be recorded or reinforced and the type of microphone to be used. First I think we need to cover some basic microphone types along with pros and cons.

Dynamic
Microphone construction is similar to a small loudspeaker.
The diaphragm moves as the sound pressure varies, producing a small signal voltage at the output.

Pros - Most reliable of all types
Cons - Difficult to achieve high sensitivities

Applications
Solo vocal mics
Lapel mics
Paging and public address

Condenser
Microphone element is actually a Small capacitor (their primary purpose is to store energy). A small voltage is applied to it with a battery or phantom power. As the sound pressure varies, the voltage is "modulated" by the diaphragm movement.

Pros- High sensitivities can be achieved. Good for remote micing.
Cons - Requires battery or phantom power. More fragile than dynamic mics.

Applications
Solo vocal mics
Lectern mics
Choir mics
Pressure - zone mics

There are other microphone types such as ribbon, noise canceling, electret condenser, but they are primarily used in recording, and specialty applications, i.e. announcer mics, factory paging, aircraft. 

Church Systems - should they be Mono or Stereo?

Churches have migrated from the bullhorn and soapbox to fairly large complex sound systems. Most church buildings today are not designed for sound, so even the smallest church building needs a good sound system. Why do churches go through at least 2 sound systems before they get one that really works? The common errors in purchasing sound equipment, is that the music stores don't usually have the church's best interest at heart. Do they have the necessary skills to determine the church's needs? Do you think of speech reproduction first? or Do you design for music reinforcement? Most churches end up with a sound system that doesn't meet their needs.

All churches need 2 sound systems (a mono system for speech and a stereo system for music)

The most economical way to achieve that is a dual function sound system. What is a dual function system? It is a Left/Center/Right configuration. The L/R is used during the worship portion of the service and the Cluster (center) is used for speech reinforcement. You can get great sound for both your pastor and the musicians by carefully planning, and understanding the dynamics of a dual function system.

The criteria for those systems: even and full bandwidth coverage to every seat in the venue
If your facility is 5000 seats or less you do not need multiple speaker layers on delays

You can achieve full coverage with the latest LINE ARRAY technology (a vertical stack of multiple speakers). In fact most concerts that you go to today use the same technology but run it in single channel (mono) mode. (The area of coverage is too big to have stereo sound)

An oversight that I often witness in sound system design, is the failure by the designer to differentiate between speech and music. The assumption that a spacious sounding music system will reproduce speech in an acceptable manner can be an expensive one. The quality of music reproduction, is very subjective. Like art, there is no absolute criteria for good or bad. Speech on the other hand, can be judged on the basis of intelligibility. It is possible to assign a quality score to a sound system's ability to reproduce speech.

The criteria for proper reproduction of speech and music are almost the opposite.

A simple example helps illustrate the point. A choir in a reverberant space sounds very pleasing to a listener during a musical performance. Ask the same choir to read a sermon to the congregation and there will be total confusion. The timing inconsistencies and pitch variations that make the musical performance a pleasing experience can only confuse speech. Placing too many loudspeakers, with the inherent timing differences to various listener positions can have the same effect. The implication is that for a system to excel at music and speech, it should be a multi-channel system in design.

Criteria for Optimum Speech Reproduction
Single point of origin (center speaker system)
No reflections within 10 ms
No high-level late reflections (>50 ms)
Positive direct/reverberant ratio (Reflective sound often hinders  vocal intelligibility)

Criteria for Optimum Music Reproduction
Several points of origin desirable (at least a two point of origin speaker system. L/R stereo)
Comb filtering can change the tonal character of the direct sound field in a pleasing way
Negative direct/reverberant ratio a plus for many types (organ, choral, symphony)
Reflected sound desirable

Church Sound Systems - Update every 5 years?

It seems that every 5 years from an install I get a call with comments like "Our system just doesn't sound good anymore" or "We need a better system". If the system was great 5 years ago why the indifference to it now? The answer is that we quickly get used to the way it sounds. The best remedy to an ailing system is to have it tuned. Every sound system needs to be tuned at least twice a year.

• In the spring when the temp starts to warm up
• In the fall when the season changes and we start to wear heavier clothing

This will keep your system sounding "fresh" or "new" If you need an understanding of the tuning process, download the eBook "Tuning Your System" from the downloads page.

New Site in the works

News!!! We are updating the site. Checking out a new format. It has a good blogging feature and podcasts as well.
What do you think?