In my first job as a teacher, I was called upon to talk at a meeting of prospective parents in the school hall. By chance (or was it malice on the part of my colleagues) I was put on first to talk about my area of responsibility, and I found myself in front of a rather squeaky and unreliable sound system.

I chatted away, and did my bit despite the squeals and squawks, and handed over to the Head of Sport, who deliberately stood to one side of the mic, announced in a booming voice, “I don’t need artificial aids,” and proceeded to make me look a bit of a turnip for having used the amplification.

Not my finest moment, but the fact was that for people of average voice, it is hard to be heard at the back of the school hall when it is full.

In fact if you think about speech day, sports day, the swimming gala, the dance class, or any situation when you’ve got a spot of laryngitis, if there’s no amplification, it is hopeless.

What my school was doing (I discovered after that first humiliation) was trying to get by with a rather cheap bit of kit that came from the Far East, and it was only when it failed completely while the head was addressing the good and the great of the town at speech day that we decided to get the system sorted once and for all.

Of course different situations need different systems. I pushed for (and eventually got) a system that could be used as a PA system at events, and could change the speed of music in my dance classes. (The Head of Sport didn’t like the fact that I’d introduced dance into the Sport department – but it was very popular – and in the end Ktrvapes even he admitted that the system did help the swimming gala.)

But you don’t have to go that far. There’s the Entertaina for up to 150 people, the Entertaina Plus USD (which allows the playing of the CD as well as your speaking into the mic – ideal for sports events and the like). The one I managed to procure with its variable speed system is the Entertaina Plus PC 30.

However there’s always someone who is opposed to spending money, and in this case my head of department decided to have one final go at me. “How many decibels has it got?” he asked when I proposed the new system at a staff meeting.

It was in fact a meaningless question, but as a result of it, I went and looked up decibels and this is what I found out. It doesn’t have much to do with amplification equipment, but it’s quite interesting.

140dB Harmful to hearing
130dB Above this it starts to be painful
128dB The loudest scream by a human recorded at a distance of 2 meters
120dB Disco when standing near the speakers
110dB Live rock band – can lead to hearing loss for musicians
100dB An electric mower or a tractor passing close by
90dB Open top car ride on motorway or a food blender which you are operating
80dB Very noisy alarm clock, or a kitchen waste disposal unit
70dB Vacuum cleaner
60dB Normal conversation at 1 meter
50dB A quiet office
40dB A dripping tap
30dB A soft whisper
20dB The background sound in a broadcasting studio
10dB Leaves rustling close by
0dB Threshold of hearing