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[michaelogr]

AUDIO EDITING SOFTWARE

Audio editing software is easily available nowadays; some of it very cheap indeed (like shareware or freeware). It is tempting to use such software to 'enhance' apparent voices or other paranormal sounds. However, there is a serious problem with this approach. While it is true that you can reduce distracting background noise from a recording, the process is not perfect and it inevitably alters the sounds permanently. Audio editing software can certainly make ordinary, real human voices in a noisy recording sound better. If, on the other hand, you have recorded a random noise that just happens to sound like a voice, repeated use of noise removal, filtering, etc, can make the noise sound more like a voice (even though it isn‟t one). You could end up listening to an artifact of the overuse of audio enhancement rather than a real voice! For example, suppose you hear something faint in a noisy background that could possibly be a voice. If you apply filtering and it sounds more like a voice, though still unintelligible, there is inevitably a temptation to do more filtering, to see if it gets clearer. If you continue to apply 'enhancements', the process may exaggerate the features that are voice-like even if it isn‟t a voice. Worse, 'enhancement' can even introduce 'new' features to the sound that are just artefacts of the process, rather than real recorded sounds. Audio enhancement software is not 'intelligent' - it does not „know‟ you are trying to enhance speech from noise. With each repeated run you just get further and further away from the original sound until, ultimately it may be completely lost.
If you really must use audio editing software on your paranormal recordings, never apply more than one or two 'enhancements' per sample and apply exactly the same process to ALL your recordings. If you apply different types of 'enhancement', to different degrees, to each recording, then you will not be able to objectively compare samples. In some noise reduction processes you have to nominate an area of the recording as „noise‟ so that it can then be removed from the sample you are interested in

In general, most audio editing software is designed to edit and enhance sound clips of voice or music with a reasonable signal to noise ratio. It is not usually able to recover faint signals from significant ambient noise, which is a typical scenario in paranormal sound recording. For this reason, the tools provided in non-specialist audio editing software, such as noise removal, may be too aggressive for use with paranormal sound recordings. Such software may be fine for removing an annoying hiss from an otherwise clear music recording. It should leave the music relatively untouched. However, when used to try to enhance faint paranormal sounds, it may change them so significantly that the results are of no use as evidence. This is why, ideally, you should aim to avoid all such audio enhancement. You should, at the very least, always keep an original unedited copy of your recording for later research. If in doubt – don‟t edit!

[PGR-IN Chris]

I'd agree with most of what you said Michael.  Too many ppl today take for granted that audio is just there without thinking about the fact that the changes/editting they are doing is possibly/actually corrupting/adding/distorting what is already there.

[CaveRat]

That about covers it!

I don't use any enhancement on any EVP recordings, ever!   I do sometimes play recordings through filters, etc. while in the process of analysis, but I never alter the original.  If for example I find that adding 6 db at a certain passband makes it easier to hear, then I simply note that for future reference. If someone else uses my recording they have the option of adding that same enhancement if they want too. They can duplicate my efforts or they can try new enhanements of their own. If they find something different they can provide their comments and I can duplicate their settings as well.   But in every case the original is unchanged and others may either duplicate previous work or try their own as they choose.

[UberGeek]

In addition, I recommend the use of a "Evidence Manipulation Log".  This allows for "repeatability", so you can distribute the original, as well as the "marked up" cut, and everyone should be able to reproduce exactly what you did.

Also, keeping tabs on the software version numbers used, plugin versions, etc.

To add another layer of repeatability, I would also suggest using open-source audio software.  So, if someone suspects a module in the software, ie the "Amplify Sound" plugin, is causing it, then it can be tested by modifying the source code of the module, and testing that.

[CaveRat]

I am always afraid that when "marked up" versions are released that they have a way of getting separated from their maanipulation logs and being considered original.  Of course that is the result of sloppy management but none-the-less it happens if one is not careful.

Absolutely right regarding versions, plug-ins, etc.  Some time ago I did an experiment using a manufactured "EVP".  (This was done so the actual mesage was known.  Only later alterations made it sound like a true EVP.  The point is this was listened to using different computers and codecs.  While the Class A "EVP" was almost uniformly processed correctly, the subjects had differing interpretations of the Class B one and still wider discrepencies with the Class C one.  This was to be expected.

But where it became interesting was when the subjects switched computers.  For the most part the interpretations stayed with the computer, not the subject.  That is everyone using one computer tended to get a similar interpretation regardless of their own efforts.    This was done using a series of similar "EVPs" created with similar phonetic makeup, so the results were not clouded by one's efforts with a previous decoding session.

Conclusions reached were that (A) the codecs made a difference in interpreting an EVP, and (B) Discrepencies tended to be reduced as sample rates were increased regardless of the codec used.   In this case my sample base was small, I would like to repeat this experiment sometime using a larger representative sample and more "EVPs".  That might provide more meaningful data.  But even as it was it raised some interesting conclusions.

[Spirit Seeker]

The only thing I use audio software for is to cut a portion of the audio and save it. I never enhance it in any way.

[SpiritHunter]

I agree with that Spiritseeker and caverat. I prefer to present audio in its original form to my clients. I only use the software for clipping and saving clips. I have used filters in the past but I choose not to use them. Integrity of the original audio is always in mind.

Good topic Michaelogr

Cheers,

Miles

[DANNY]

why not do both  show the client a before and after

[PGR-IN Chris]

Thats what we do Danny.  We always keep the original in its uneditted format (if analog, it stays anlog; if digital it stays digital).  If we do any manipulation to it (short of just time editting) we allow them to hear the original and then the modified version.  We also stress that because it's modded, we cannot definatively cast judgement on it (as different ppl hear different things from different sounds.  Nor will we speclate what a modded sound is actually conveying.  Too many "Buts and Questions" can arrive from modded versions of audio capturing.

[Spirit Seeker]

Just don't see a reason to.