Yes, this makes a horrible mess of your recording, but I'm afraid that's inevitable - it's intended for a restricted bandwidth carrier, and it only has to be intelligible - no niceties like quality come into it, I'm afraid. You may also like to experiment with the speech volume leveler, but if you do, then don't go beyond 'medium', and you will probably need to re-normalize afterwards, to get the signal back as close to 0dB as you can. Then open the Hard Limiter, and select the 'Limit to -1dB' preset and apply that. So in Normalize, select the 'normalize to -.1dB' preset, and apply that (if that's not on your system it's easy to make).
Everything you need to fix this is in Effects>Amplitude and Compression. This optimises the signal as far as the level is concerned, but you are almost bound to have too much dynamic range in it.
This means that to start with, you need to normalize your signal so that the peaks are almost at 0dB. File Converter - For the Output Format, select u-law WAV (8Khz, Mono, u-law). If you have an existing file, but it is in the wrong format, convert it using one of the following options. So what you have to do is optimise your speech recording to fit in with these essentially restricted parameters. CCITT, u-law, or a-law codec.wav file format 8 KHz sample rate 8 bit Mono audio Notes: The maximum recorded file size is 5 Mb. So that gives you a signal to noise ratio at the very best of about 48dB, and that's worse than an old cassette recorder! You have to bear in mind that 8-bit audio has a significantly higher noise floor than 16-bit audio - if you want to work out where it is, it's 6.02dB/bit. Typically, mu-law compressed speech is carried in 8-bit samples. It is widely used in the telecommunications field because it improves the signal-to-noise ratio without increasing the amount of data. Nothing really - it's what you haven't done that makes the difference here. Mu-law coding is a form of compression for audio signals including speech. The original file was a 44100 Hz 16-bit Mono that was crystal clear. These settings worked for my Verizon VOIP system, but the quality is horrible with a lot of hiss in the background.
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