In this project, a lot of our work was based on setting the stage for the concert. This included placing all the instruments and amps on stage correctly, but also learning how to connect and use the PA system to make sure everything will work on the night and we know how to troubleshoot any issues. This is important for a performer especially if you are putting your own gigs in pubs or clubs, as a lot of the time you won’t have a live sound engineer with you and you’ll have to set everything up by yourself. However, in a larger venue or arena that huge artists play, the performer won’t have to do anything other than soundcheck as their own live sound engineers can check that everything in the signal chain is working, the levels are correct and there are no audible issues.
Week One
During our first week in our live sound workshops, we learnt how to set up a common stage. The first thing we did was grab all of the necessary equipment from the storeroom, like the speakers, drum kit, guitar and bass amps, microphones and cables. We were told where to put everything on stage, for example, the drum kit in the back centre, vocals microphones at the front centre, guitar and bass amps at each side of the drum kit and the PA speakers on the front sides of the stage facing the crowd.
The next part was to set up the speakers so they would work in a live situation. Grabbing the right cables from the box was the first part, and trying to ensure that they were about the right length so there wouldn’t be any trip hazards from long wires trailing on the floor. The first thing to do was give the bass bins (the big speakers at the bottom) power. We used Speakon cables to do this, plugging the end into the AC power input, and the plug into the nearest socket. We have to give these direct power as they are ‘active speakers’; if they were passive we would instead use an amplifier to give the speakers power. Then we had to give power to the main speaker that sits on top of the sub-woofers. To do this, we simply connect another Speakon cable from the sub’s AC output to the input of the speaker above. Now that both speakers have power, we then connected an XLR cable from the ‘x over’ output of the sub to the ‘balanced link’ of the main speaker. This means that any low frequencies will only go through the sub, and any high frequencies will only go through the main speaker, ensuring we don’t damage the speakers by putting the wrong frequencies through the speaker cones. Finally, so we can get sound from the mixing desk through and out of the speakers, we plugged another XLR cable from the ‘signal input’ of the sub to either channel 7 or 8 of the ‘line out’ section of the D-snake, depending on which side of the room our speaker was placed on. Here is a video depicting what the back of the speakers looked like when we had plugged every cable in correctly:
The D-snake allows us to connect many input and output XLRs into one box in the centre of the stage, and only one Cat 6 cable has to run through the D-snake to the mixing desk at the back of the room. This makes it easier to avoid any trip hazards and makes the set-up much easier to navigate. As well as connecting the D-snake to the mixing desk and speakers, we can also connect inputs into this, meaning we plugged some vocal microphones into inputs 1 and 2, and these go straight out into the mixing desk through the single Cat 5 cable.
To then test that everything in the signal chain was connected right, we turned the mixing desk on, reset all the levels to 0, and tested the two microphones at the front. We did this by slowly bringing up the levels of one microphone to the point where we could see the sound level meter hitting around -12dB to -6dB when the singer is singing loudly. We don’t want to have this level go over the 0dB range as then the sound will start to clip and distort as the equipment cannot handle the loudness. Similarly, we don’t want the level to be anywhere under -12dB unless the singer is deliberately speaking quietly as then we won’t be able to hear anything they say. After making sure the levels are set on both the microphones, we can then bring up the master volume on the mixing desk so we can hear them through the speakers at the front of the stage.
Week Two
During week two of the live sound workshop, we set even more of the stage up. After successfully remembering how to re-setup everything we worked on last week, we then had to move onto more complex, yet extremely necessary stage setting features. One of the main things to set up was the monitors. A monitor is a speaker that faces you, the player, so you can hear either your own instrument or whatever other instruments you choose. Generally, the drummer might ask for vocals and bass, the singers might ask for their own vocals and guitar/keys, and there are many other combinations that people might prefer. Setting up the monitors are similar to the main speaker stack; you give the first monitor power by plugging in a Speakon cable from a plug socket into the AC power input of the monitor. Then you give the next monitor in the chain power by connecting them both via another double-sided Speakon cable and carry on doing this until you reach the end of the chain. Finally, now that they all have power, we need to connect them to the D-snake by using the XLR input on the monitor and plugging this into the ‘line out’ section of the D-snake. You connect this in number order, eg the first monitor of the chain being the first line out.
As well as setting up monitors, we also had to make use of DI boxes to connect the guitar amps, bass amps and the keyboard to the D-snake. A DI box means we don’t have to mic up the amps, and instead we can connect the amps directly into the mixing desk. This reduces noise and protects equipment, as well as makes the set-up generally easier. For this, we connect a 3.5mm jack lead from the output of the keyboard or amp and into the input of the DI box. Then, we use an XLR to connect the output of the DI box into the input of the D-snake.
Another important feature of a live performance, especially in a medium to large venue, is drum mics. These are self-explanatory; they amplify the sound of the drums using microphones near or clipped onto the drums or above the kit. The overhead mics are condenser microphones, and they require phantom power to work correctly. The mics near or clipped onto the actual drums are dynamic microphones. The first microphone we connect is the kick, which goes into input 1. Then it goes snare, hi-tom, mid-tom, low-tom. Next, you connect the overheads into the D-snake, with the left overhead being connected first and right after. Generally, we use the spaced paid setup for the overheads, meaning the two microphones are placed at opposite points on the kit.
As we connected more things into the mixing desk this week, we did a similar test by simply bringing up the levels of each input until we can see the sound level on the meter, and then bringing up the master volume so we can hear everything come through the speakers. We had to ensure we had the phantom power enabled for the overhead condenser microphones above the drum kit. For the monitors, this is slightly different. We choose the mix 1-3 buttons on the mixing desk, which lets us raise the level of certain instruments into a specific monitor, then we raise the master so the player can hear these instruments through it.
Week Three
This week was a test about how fast we could set up everything we have done for the past two weeks, and whether we can remember everything without having to as a tutor for assistance. We had to first set the stage (drum kit, amps, instruments, stands) then the PA system (speakers, microphones, D-snake, mixing desk, DI boxes, monitors). I think we did very well with this as we set everything up in our fastest time yet and we seemed to remember generally everything about setting up, having minimal help from the tutor.
This week too, we focussed a lot on the health and safety of the stage. Once we had set everything up, we went around making sure everything we correctly plugged in and there would be no electrical hazards. We also had to ensure that wires were not trailing around the stage unnecessarily and that they were tucked in neatly. We pushed any wires under the speakers or under the drum kit and moved the D-snake to just in front of the drum kit. As well as making sure wires were tucked away, we had to make sure there were no wires being strained as this means they could fall out of the input/output or someone could trip over wires that are above the ground. Our tutor rated us on our health and safety work and said we did very well, considering we didn’t have any duct tape or wire trip hazard covers to use.
After successfully setting up the stage, we looked a little more in detail about the mixing desk and how we can EQ and add simple effects to the inputs. To EQ the inputs, we used the channel selector to pick what input we wanted to EQ, and the knobs on the mixing desk to use high pass filters on anything that needed it, and generally manipulating the frequencies to make certain areas sound brighter or give vocals more presence, or the bass more punch, for example. Our mixing desk at college has two reverbs and two delays that we used this week. To add reverb on vocals, you would select the vocal channel and press FX1 on the mixing desk, and bring up the fader until you can hear the amount of reverb you want. This is the same for the delay effect, but you press the FX3 button instead.