File Conversion

A question I keep forgetting to ask .. here's the scenario:

* Voice talent emails me dry voice on MP3
* I start producing the commercial .. then have to shut Audition down to re-start the next day

Here's the question .. do I save the dry VO file as an MP3 or as a Wave? Does conversion to Wave alter the quality? I have always done this and now I'm wondering whether I should. Bear in mind that I often do not have the luxury of time to create a new working folder containing the dry voice and workparts, it's sometimes a rush job and items are pulled form CDs, emails etc and the project is built on the fly.

My rule is always just convert from mp3 once, then keep all the work in progress as wave files. Then finally re-compress if the client or transmission method requires. So while you are working on the client's voice it should be saved as wave.

Always keep the compression/decompression operations to the absolute minimal possible, and remember that the client's compression and decompression at his end will be added to yours and you probably don't know where he got his codec from.

Yup, a wav file. Every time.

...Does conversion to Wave alter the quality? I have always done this and now I'm wondering whether I should. Bear in mind that I often do not have the luxury of time to create a new working folder containing the dry voice and workparts, it's sometimes a rush job and items are pulled form CDs, emails etc and the project is built on the fly.

It's the conversion from wave back to mp3 that should be avoided as long as possible.  A wave decompression of an mp3 will sound bit for bit like the mp3 -- there is no alteration of quality.  But for convenience, and to avoid accidently recompressing, I agree: convert once to wave and keep it that way.

There's an interesting discussion developing on this subject right here.

Thanks all. Re-encoding back to MP3 is unavoidable as the final productions are invariably always delivered as MP3, bit somehow, a voice-over or work-part that was originally MP3, then encoded to wave and back to MP3 in the final mix and after eq and prosessing bears no signs of this re-encoding mania. Let's not forget that the only reason MP3 is there in today's daily equation in the production world, is small file-size for fast internet delivery. If the internet didn't exist we would still be mailing and couriering tapes.

If the internet didn't exist we would still be mailing and couriering tapes.

You mean that we spent all that money on ISDN systems when we could have used a courier instead?

All that money is correct! Why is ISDN so bloody expensive? Never used it myself. Before MP3 and internet you had this situation of the same 10 voice-over artists voicing all the ads in the country. They spent their time going from station to station for "voice-over sessions" (did a few of those myself) and voicing from home using ISDN - which they could afford because they hogged all the work. New VOs had a terrible time breaking into the business because it's hard to justify the expenditure of ISDN before the security of work. I recently came across a woman VO ISDN veteran who was still so much in shock at having to work in MP3, that she felt it right to charge an extra £5 for every MP3 voice-over she did, for the effort she had to go to, to buy a copy of Adobe Audition and edit her voice-overs and to pay for the emails she had to send! .. I told her that having a copy of AA or similar and sending emails are necessary pieces of kit nowadays and no one charges extra for it .. her earnings expectations must be down this year

All that money is correct! Why is ISDN so bloody expensive?

The pricing structure goes back to when this was the only form of digital transmission available on a geographically wide basis - so it was all based on scarcity value. Which is why it was quite common for some large-scale users and firms to provide a local facility for others to use - most people simply couldn't justify the cost on their own. But inherently there is no reason for why it should be expensive nowadays - except for the fact that you still  have to have a high-grade line installed for ISDN if you want to use if for broadcast purposes, because ideally it has to be a 256k line; the basic 128k is barely sufficient.

But it's changing. I don't think that the internet and exchanging MP3 files is going to be the only answer, because that doesn't provide one of the important things that a lot of broadcasters still want - i.e., the possibility of doing relatively high quality live links. There is one internet-based facility that does though - and that's VoIP. This is basically what Skype uses, and it's also the same system that all mainstream telecom providers are now using (albeit at a lower quality level) for international call routing anyway, even if you are using a POTS phone at home. I don't think that most people realise this - it's the primary reason that international calls have gotten a whole lot cheaper over the last few years.

The system isn't perfect - it still needs work doing to make it more secure for broadcast use as far as I'm concerned, but I think that when it's finally sorted out, it will make ISDN-based systems quite obsolete, and a lot of people will use it for sending short files anyway, simply as audio - just as they have in the past with ISDN, leaving the person at the other end to record the stream.

Thanks Steve. Actually it's a good time to look into Voice Over IP, we've all heard of it but is it usable for doing live radio shows, interviews etc? You mention SKYPE, and presumably people could use any instant messaging system like Yahoo Messenger or MSN at at both ends with a decent mic, is that how it works?

Actually it's a good time to look into Voice Over IP, we've all heard of it but is it usable for doing live radio shows, interviews etc? You mention SKYPE, and presumably people could use any instant messaging system like Yahoo Messenger or MSN at at both ends with a decent mic, is that how it works?

Pretty much, yes. Skype works rather better than POTS for interviews and other telcos, because you get pretty good quality and you don't need a TBU. It's quite easy  to arrange to record both sides of an Skype interview on separate tracks using Audition and a small mixer - I've tried it between here and Australia, and apart from a few delays and a bit of dropout, it works fine. If you do it locally, it works much  better - basically without the dropouts.

But there's a lot of other software out there too - not just Skype. Some of it uses other variations on the protocol, and some of it is suitable for wider bandwidth stuff, and also some  of it has better security - I don't actually know at present what is good to use for direct broadcast purposes, because I haven't investigated that side of it very much, but I may have to shortly, for a client. Then perhaps I'll have a better idea of what is feasible.

As far as recording VoIP is concerned, there is also some software that will let you record each side of a call separately anyway, without using Audition or a mixer at all. Once again, I don't currently have any recommendations, but it's certainly a growing market with quite a few variations on the theme.

There's a program called Source-Connect that seems to have a lot of pros standing behind it.  I've used it and the quality is superb, but it is not as solid as ISDN and, at the moment, it's pretty much one-way.  Also, the latency becomes an issue, as it's 4-5 seconds.  But they're always working on it, so I have no doubt that it is constantly improving.

There's also the Comrex Access, which uses audio over IP.  I don't like it at all.  The quality is very hit-or-miss.  When it's good, it's really good.  When it gets goofy, it is the most irritating thing in the world.

There are also some POTS codecs that sound extremely good, though I would never use one for professional VO work.  For remote broadcasts, however, they are outstanding.  Most often, I use a Matrix.  I would say the quality rivals that of an 80-96kbps mono mp3.  Considering that there's two-way communication and less than a half-second of latency, it's pretty impressive over POTS.

Emmett