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What is ISDN?

Communication Masts

ISDN (or Integrated Services Digital Network) is a communications technology from the late eighties, when phone lines and landline telephones were the main method of telecommunication.

In the nineties came dial-up internet, and people would use a modem with their analog telephone line to connect to the internet. However, the connection was slow, and in the process tied up the entire phone line meaning no phone calls could be made or received at the same time.

ISDN provided a way around this problem. It allowed a voice conversation and data connection to happen at the same time and it also offered a higher bandwidth allowing faster connections to the internet.

This is how most businesses use ISDN, but professional voice overs use it in an entirely different way – as a CD-quality phone line that connects their home recording studios (via the use of an audio codec) to studios around the world, allowing their clients to listen in and give direction, and also record their voice performances. The sound quality on a correctly configured ISDN line is almost as good as being in the same room as your client or collaborator.

The Death of ISDN

At the timing of writing this, ISDN is being phased out in the UK. By 2025, it will cease to exist and no more new lines are being added from 2020.

Broadband internet now satisfies the data requirements of nearly all businesses without the need for expensive, slow and outdated ISDN technology.

What Does This Mean for Voice Overs?

Thankfully, there are now many reliable alternatives to ISDN that have been tirelessly tried, tested and improved over the past decade. Audio professionals can also use their broadband connections to link up with each other for podcasts, radio interviews, or voice over recordings, and these broadband-based connections are often free!

Free Alternatives to ISDN for Sending Audio / Recording Live Voice Over Sessions via the Internet

Source Connect Now and Clean Feed are both applications that run in your web browser and allow you to connect for free with others who’ve also loaded the application.

The audio connection is reliable and of excellent quality and can be made fail-safe with the following steps:

  • As a voice talent, presenter or interviewee, run an audio program in the background that also records your microphone. This way, if there are any audible data glitches or buffering problems during the web-based audio link, you’ll still have a pristine copy of the audio to pass on by e-mail after the recording session. Audacity is a free digital audio editor that will do this job well.
  • Connect your computer to the internet using an ethernet cable (You may need an adapter if you are using a newer Mac). Ethernet gives you a higher bandwidth and more stable connection compared to connecting by WiFi to the internet, which is likely to help your audio connection run more smoothly.
  • Select a connection rate that’s not too high. 128K mono is perfectly suitable for most voice recordings, and it won’t overwhelm your bandwidth: The less data you send to less likely there are to be problems with the link.

Premium Alternatives to ISDN

If you’re an audio engineer who’s making a lot of connections to international voice artists, or interviewing people from around the world, Source Connect (full) is a popular way to go.

I’ve used it in my studio and it allows even more stable internet-based audio connections. Its main selling point is that producers can take the audio directly into their DAW (digital audio workstation) and edit on-the-fly as they record a voice talent. This is a big plus point for producers who need to quickly record a lot of audio (e.g. for eLearning courses or audio books). By contrast, with the browser-based free versions, often just the recording is taken during the live connection and it’s then replayed and edited at a later date – taking twice the amount of time.

ipDTL also offer a range of paid-for services that facilitate pro audio connections. SIP audio in particular looks very useful for both voice calls and top quality audio connections – a one-stop shop for the small audio business owner.

Loop Back

To use a phrase from the days of ISDN, now seems like a good time to loop back to the beginning of the article and mention that if you still need to make an ISDN connection, even during and after the phase out, IPDTL also offers an internet to ISDN service, where you can call an ISDN number from your internet browser and send audio from whatever is connected to the audio input of your computer; in my case an audio interface phantom powering my Rode condenser microphone.

So, ISDN for voice overs lives on! (but only for as a long as the physical ISDN lines still exist).

Connect / Contact / Communicate

If you’re looking for a professional voice over actor who has a professional home studio and offers Source Connect, ipDTL and Clean Feed connections, look no further.

I am available for voice overs every week day and can work with you via the internet wherever you are in the world.

Please get in touch to discuss your project.