Voice overs and ISDN
In case you were wondering, ISDN stands for Integrated Services Digital Network.
In sound recording (without getting into all the technical stuff) it’s a way of connecting two studios together with very little loss of quality. So I could sit in my studio in London and connect with someone in the States who also has an ISDN line. It looks just like a phone line with a fancy box on the end. In the UK, not surprisingly BT is the main supplier.
Surely it’s not that simple?
It certainly isn’t. The sounds going into a microphones in both studios have to be digitized so they can be sent on the ISDN line. This means both studios need a codec
What’s a CODEC?
Short for coder-decoder it turns the analogue sound into digital and vice versa. My codec is a Pronto 2 and looks pretty much like an amplifier. I speak into a microphone, which is connected to a small audio mixer to control sound levels. This is connected to the codec, which is connected to the ISDN line. At the other end, the other studio receives the signal into their codec, which is then plugged through to their recording equipment, and they monitor it through headphones or speakers.
There are various other codecs.
Prima springs to mind, and is very popular. A software application called AudioTX has also been developed which means your PC effectively becomes the codec. I hope to look at this in more detail in the future, but a good run down of equipment suppliers is at BroadcastISDN .
So what’s the point of ISDN?
Local radio stations love it. Instead of having to use the same voices living locally, or those prepared to travel on the circuit, they can now choose anyone in the world with an ISDN line and the rest of the kit. Voice overs love it because they can stay at home (wherever that is, maybe miles from civilisation) and not even get dressed to go to work! Well that’s the theory, of course it’s not that simple.
But more of that next time.