Event at VIVO + Analysis = Chance to Learn!!

I guess most of you can see by now that this post will be another one of those where I go and dive deep into PA stuff and then leave most of you out there gasping for breath as you try to surface to get a bit of air before you go back in again...
Well, you could say that its becoming a bit of my hobby, but I think its quite nice, and as Eng Yian as kindly put it, we need a LOT of case studies...

So anyway, I was at vivo city today to eat lunch (after ventures) and it turns out that they like to wander around before eating lunch. I happened to run into a PA set-up for a concert to be held at the roof tops of vivo city and... lets just say that I decided to take a closer look =P

Before we go in any further, lets have a brief overview of what the event is about:
This concert is a part of the crime prevention campaign that is being held at vivo city (no prizes for guessing why). Anyway, they had gotten in a PA crew to set up for the concert that they are going to have, and lets just say that the first look of the set up is enough to make me stand up in awe!!...

Anyway...
As you should be able to see by now, the title of the concert is... yup: "Roof Top Jam Dance Party". They mean it quite literally, as the dance party part is happening in the night, but the concerts are still held in the morning and afternoons.

And before we go and plunge our head in, lets have a general overview of how the set up looks like, shall we?

Now as you can see from the picture, this is an outdoor event. However, their set up can rival even that of the most expensive indoor PA system. We will be going in-depth into each section after this brief overview, but lets take a look at the environment first.

Firstly, since the event is held at the roof top of vivo city and is also an outdoor event, the speakers and amplifiers need to be strong enough to overcome the large amount of noises that will be flooding the event spot. As stated by the golden rule, people absorb sounds, and this is further aggravated by the fact that it is a wide open area. Thus, the speakers and amplifiers need to be strong enough to be able to project the music that is to be played to the large audience that should be present there at night.

Because of a lack of reverberation, there can be firstly a lack of warmth in the music. Warmth in music is created through reverberation of the sound wave around the venue. This can seriously hamper a band's attempt to bring soothing and warm music to the audience as the effect may not be there.

The remedy for this would be to either create a separate foldback for the audience that creates an artificial reverb by setting delay using an equaliser, or if the mixer is high-tech enough (Allen&Heath PA12 has this functions), it can create an echo in the main mix as well using the sfx functions. This way the warmth can come back...

Another important thing that the PA crew has done is to set up two separate group of speakers. One group is set to face the audience that can have a seat and watch the event while the other group is set to face the rest of the crowd present at the event. Before we go on further:

If you can see in the picture on the right, the large dome structure that you see standing there is the place where the concert is held. If you noticed from the picture of the overall view above, the event is actually facing inwards towards the audience. So what about those that are at the event but are not seated? The PA crew has them covered and has set up the other group of speakers that I had mentioned to take care of them.

Lets take a look at their speakers that they have set up for the rest of the audiences:
Now, notice that even though this could be considered an auxillary speakers for this event, it is still very large and seemingly very powerful. This is to compensate for the fact that they need the music to be able to cover almost the REST of the rooftop. This way, the dance party can then be carried out and also at the same time, important announcements can be made.
They had also done a good job of splitting this speakers into twitters and subwoofers. This would sure allow the speakers to pack a punch during the dance as each speaker do not need to cover a large frequency range and thus prevent sound distortion. At the same time, it can provide the booming chords needed for the times when you need to get people's heart racing during the dance.

Now, lets head over to the main group of things shall we?
Lets take a look at the... SPEAKERS!!

I must say I am very impressed by the speakers, just take a look at it:

Yes, if you still can't see it, its composed of 3 twitters along with 2 subwoofers (OK, one of the twitters seems to be blocked out). Evidently and also based on some of my assumptions, this is a bi-amp system that uses a crossover to allow each speaker to only have to project a limited frequencies of sound. Before you start going on the question of how many amplifiers they need to do this, let me explain the wiring for their speakers...

Their tweeters are all connected to each other. The idea is something like, they have 2 NL4 jacks behind, and one of them is an input while the other one is an output. (It looks that way). One of the speakers receives the signal and then transmit the signal on to the next speaker. This means that the amplifier powering this set of speakers is probably a bit powerful so that it can do that, but whether or not this is even possible still leaves a lot to be discussed (perhaps we can go and take a look again?) The two subwoofers however seems to be separately wired for the event...

Now, we always hear complaints from performers that they can't hear themselves, but I think this crew has really taken it very literally...
Yea, as I have mentioned, I feel that they have taken it way too literally. If you count all the black boxes on stage that are acting as the stage monitors, there are approximately... seven stage monitors. 4 in the first row, 3 in the back row.

I don't think this is a good set up because there are just way too many stage monitors, and just too many way for feedback to occur here with seven stage monitors. Face it, if seven stage monitors are on at the same time and they are THAT freaking close to a mic... I hate to imagine what would happen. Even Mel was asking how is it possible...

As it turns out, the crew did suffer quite a lot of problems. I was there when the event just started, and they ran into several monstrous feedbacks right at the beginning and then it evolved into an endless whining from the speakers coming at around the high-mid frequency (although I think this has to do with the wiring... More on this later)

Either way, 7 feedback monitors is suicide, but might just be needed for those sort of rock concert that they are going to play around with. And lets just say that we had more then enough of rock concerts for a while after the end of year celebration (I am soooooo not going to get started on that)

Anyway, I went to take a look at their mic placements, and I guess there is somethings we can learn from there as well...

This is their mic placement for their drum set. I know it doesn't look very clear (The camera isn't that powerful). But anyway, there is a mic for each drum and each cymbal. So basically, the WHOLE drum set is mic up to the speakers...

Did I just say that?!

Yes, everything is mic up, and I got no idea how they are capturing it. But I think basically what they have done is to ensure that the gain on this mics are not very high and they use super-directional mics to ensure that they won't pick up the rest of the sounds from the other drums creating a super powerful drum sound coming from the speakers. But it does show what we can do with a lot of mics and a lot of mic points...

Next up, some of the mic placements for the players:

Yes, their mic placement for their saxophone players are very good. If you can see it in the picture, the saxophone mic just happens to be positioned at the correct place for the sound from the saxophone to be captured easily by the mic.

Also, before we move on to the next section of our event analysis, it is to be noted that most of the mics that are used either uni-directional or super-directional. This is to ensure that the mics will capture from one and only one sound source. This will allow the peopel up there to control all the inputs and outputs easily and also prevent situations where a certain sound overpowers the rest because it is picked up by the rest of the mics as well.

Oh yea, just a note before we move on to the lights system.
For all their keyboards, guitars and what-not, they have given them direct insertion boxes, ie DI boxes to send the signal up to the mixer. Its good as it minimizes the problems of using a portable amplifier (end-of-year celebration comes to mind) and also allows a good input to be received to be sent to the speakers (no distortion, no nothing). Unfortunately, the pictures for this section seriously cannot make it, so we're not putting any up here...

Next up, we're onto our lights.
As already mentioned, this IS a dance party (at night that is) so obviously you'll need something to fire up everyone's mood (although a dance party in a crime prevention campaign doesn't seem to exactly fit in). Anyway, lets take a look at their lights...
First off, we go into the simple stage lights, also known as par lights.

If you had noticed by now, this is an outdoor event. Why do I say that this set-up can rival even those of the indoor events? Well, just take a look at the lights...

All those black little things at the top are lights. Their power cables are wired by connecting it to the lights (obviously) and then coiling the cables around the metal all the way until it reaches the source of the electricity. Sure it takes time, but it sure looks good once its done (especially when you can't see the cables easily)

And before you think I am easily impressed...

Here is a bunch of intelligent lights, also known as intel lights. There are 6 intel lights and (not in this picture) 4 intel lights positioned on the stage most likely to provide some background lighting.

Now, I am not pro at lighting and setting up powerful scenes that uses light to convey emotions and feelings... yet. But this seems to be a very versatile set up to allow the PA crew to whip up the mood of the crowd and also generate the effects of slow moving soothing music. Lights are usually very versatile unless your set up sucks, but they may impair your performers ability to perform (which is highly evident during the end of year celebration).

Also, lest you think the lights float up there by themselves...

Here is the control for the height of the intel lights and also where they are placed. The picture is here just to show you how versatile light can be if you have the proper equipments. Tanglin secondary also has a few sets of this light holding structure, and lets just say that their intel lights are the mobile intel lights...

Sorta reminds you of mobile suit gundam... but anyway...

Now, lets take a look at the wiring...
This is where I think the PA crew has screwed up.
The wiring is brought down from the control that is located on top all the way down to the place where the stage is. They had placed all the cables along the same freaking straight line. That includes balanced cable, power cable, light wiring, receivers....

Did I mention lights and sound together?!
Remember me talking about the high-mid whining coming from the speakers? At first I thought it was a ground loop (which can be quite common when your ground sucks or if you have lots of equipments) but the frequency of the buzz is too high for a ground loop. (50Hz in the US and 60Hz in much of the rest of the world). Evidently, it can't be a ground loop, and besides if it is, they COULD have lifted the loop using the DI boxes already ("lift" function inside DI boxes will potentially disable all problems brought about by a ground loop). Its got to be something else.

I've got a feeling that it is due to the light and sound cables being placed together. The current flowing through the cables generate a magnetic field around the cable. This will thus creates the interference. Adding on to the fact that this is a constant interference, and you've basically just sealed the case.

What the PA crew might have done is to lay the lights cable totally separated from the sound cables. That way, less interference could have occurred and thus allow the audience's ear to not be pricked by the never ending high-mid whine...

Now then...
This is the control that was present there. It was located very far away from the stage. There are both pros and cons for this...

Pros
Its location allows it to be at the same spot as where the audience is. This way, the people at control will be able to hear what the audiences are hearing. This allows accurate adjustment and allows the audience to enjoy the performance at the highest standards.

Cons
Its far distance means that it might not be able to consider the audiences that are seated in front (I can imagine an audience being blasted out of his seat thanks to the subwoofers =P). Also, there can be a lot of communication problems between control and backstage bcause of distance. This can be a significant issue especially in such a dance party where the sound of the instruments crashing is often much louder then what you can hear with your ear (Trust me on this).

They are equipped however with headphones and gooseneck mics, but I question the ability of the backstage to be able to hear anything through the barrage of crashing instruments that might happen later on. Also, their's is one way, so backstage can't report anything back to control. That's definitely a seriously bad news. But it might not be that bad since there isn't a curtain...

And that's about it for the evaluation of the event at Vivo City. I had combined my evaluation of each parts as I went along describing so that you guys don't need to go back and forth on this page to understand what is going on.

If any of you guys have the chance or are interested, lets have an outing to vivo before this event is over. That way we can all catch a nice movie, spend time together and also examine a cool PA system ^^

Amount of time it takes to observe a system: 10 minutes
Amount of time it takes to evaluate and analyse: 25 minutes
Amount of time it takes to type this out as an archive: 1 hour 30 minutes
Amount of time this knowledge stays with you: Forever...

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