converting mono audio to "stereo"

[phase52001]

I have a piece of audio that i'd like to give a "stereo" sound.
Not "echo", but stereo simulation.

I believe the expensive audio software packages do this eg; Peak Bias.

Anyone aware of a cheaper way to do this?
I'm only likley to do it this once.
Can FCP, which I have, do this?

Thanks if you can offer any advise.

[michaelmcgennan]

You need [tisdu]. Contact me directly at mareva@tpg.com.au

Regards, Michael

[Case]

Searching on [tisdu], I found an interesting piece, apparently by you. Cool stuff.

[jbritt]

Let's see if I can explain this. In FCP.

1. Make sure audio wave forms are visible by selecting SEQUENCE/SETTINGS then click on TIMELINE OPTIONS TAB select the show audio waveforms box.
2. Now you can see which track has the audio by looking at the wave forms.
3. Next delete the empty track. Select both tracks by clicking on them once. Next choose MODIFY/STEREO PAIR. this separates the stereo track into separate left and right tracks. Deselect the 2 tracks by clicking somewhere else. Now hold down the OPTION KEY and click on the empty track to select it alone. With only the empty track selected press the DELETE KEY to remove the empty track.
4. Now you're going to duplicate the remaining track that has the audio. Hold down the OPTION KEY first then the SHIFT KEY. While holding those keys click and drag a duplcate copy of the track that has the audio to the line where the empty track was that you just deleted. Your holding the shift key so the track moves straight down without shifting timecode.
5. Your almost done. Select both tracks and choose MODIFY/STEREO PAIR again. You should have a stereo track now. Good luck

[michaelmcgennan]

The notes below apply to manipulating the extracted audio file. I re-mux through the DVD Studio Pro authoring procedure. In passing, I should say that [tisdu] and DVD audio, that is, 48MHZ sampled sound were 'made' for each other.

The sound is remarkably good.

Regards (to Case, especially), Michael


How to [tisdu].
Do you have a boot with a really clean crisp sound that just hangs between your speakers - that is, great mono? But still great MONO. Try this.

Extract a sample track to your hard disk, open it with a sound program that lets you edit tracks. Insert five one hundredths of a second (5/100 = 0.05) of SILENCE [nada sound, nothing, zero amplitude] at the very start of the right channel only.

ONE CHANNEL ONLY. (I find the resulting sound is 'better' with silence inserted into the right channel. Try the left if you like.)

You will be splitting the delivery of the signals to the paired speakers by this minuscule amount.

Listen to the result, preferably by headphones, or even more conclusively, burnt to a disc for listening with your normal stereo player set-up. Let your ears be the judge.

If you decide to apply this to a whole disc, this is the ORIGINAL track by track method:

I cut the top and tail of each treated track across both channels - there will be 5/100ths of a second silence shunted onto the end of the left track by what you do at the start of the right.

These BOTH-channel trims are not heard nor missed in the ensuing DAO burn, except I've noticed that when there are drones, sweeping strings, or the singer successfully holding a note between tracks, occasionally you will pick up a small click where the [tisdu] 5/100ths of a second tail and then top cuts have been made.

The solution is to join the extracted tracks on your hard drive before [tisdu]ing them, [tisdu] them as one 'song', then track cue them again where they 'stop' and 'start'. Often the drone etc., is about making two songs one medley piece in concert anyway, but traders out there do like their track cues.

Which leads us to the RECOMMENDED whole disc [tisdu] method:

If you can extract an entire disc as one unbroken 'track', you need only [tisdu] the whole thing - one bit of silence at the start introduced into the right channel is usually in the fade-up section, and thus doesn't require cutting out; and the resulting bit of silence at the end in the left channel is usually 'in' the fade-out, and thus also goes unnoticed.

Then, however you normally set track cues for establishing individual songs prior to burning a disc, the [tisdu] effect will be present in EACH song because it was universally applied to ALL songs.

How to actually step by step do this and the programs that work best in the Windows environment is described in the Files section of the [tisdu] Group at Yahoo Groups, http://groups.yahoo.com/group/tisdu


Now, after all of the above, a proviso or two.

[tisdu] is not so much a fake stereo as a speakers-wide, space-between-them-filling, 'thick' mono.

On headphones you CAN clearly hear different sounds from different channels (just like stereo), but this is an 'accidental' effect of the slight delay of the same sound reaching different speakers.

Headphones off, in your loungeroom, on your crank-it-up stereo, [tisdu] is more about recreating big concert hall ambience than it is about assigning particular instruments to different tracks and thus specific speakers as a producer in the studio would do.

Living in Australia, and unable to resist silly plays on words, [tisdu] is short for -

Teased into 'stereo' Down Under.

Sorry 'bout that. It sounds better than the name it answers to!

Second proviso: [tisdu] is not a cleaning-up process. If I am capable of fixing drop-outs, removing clicks or otherwise banishing digital flaws, then during the [tisdu] process I will do my best to get rid of them.

Well-known cuts in tape sources, drop-outs, patched together versions, things known all too well to boot collectors, [tisdu] simply faithfully replicates.


Programs that will [tisdu] -

Amadeus 11 in Macintosh
Audacity (versions available for all platforms, downloadable free, from http://audacity.sourceforge.net/)


[tisdu] Tips:

In the sincere hope that traders are having a little play with applying [tisdu] to some of your sets, so we can all build up the database of [tisdu] sets around, I'd like to offer up a couple of observations and tips to help 'improve' your results.

1) Pump Up the Volume:

I find [tisdu] works 'best' with some grunt in the signal, so if the originating source is soft, it doesn't hurt to increase the amplitude (that is, the 'volume' of the signal - but make sure you keep it well short of peaking too high in the louder bits to avoid making new click sounds) before [tisdu]ing.

2) 'Balance' How You Hear the Volume

The other thing [tisdu] does with the silence introduced to the right channel is give the left channel more apparent volume.

Someone else described this as a "slant" to the left channel.

My usual 'solution' is to decrease the amplitude in the left channel to 80% of the right before burning the disc.

Then, when played back on your stereo, the 'slant', or apparent volume edge in the left channel is compensated by the actual volume edge in the right channel, and to the ear, they are equal.

It's just a wrinkle in the [tisdu] process, and it basically comes down to you trying out the channels' comparative volumes by burning a couple of variations - left channel 90%, 80%; or go the other way, right channel 120%, 130% - to a Rewrite CD, and actually listening on your stereo system to make your call on what's working best to apply to the set you are working on.

3) How to un[tisdu] - in the absence of an original source of the music.

If you don't have the original, and you don't want to wait for a trade to unfold to get it, the following procedure is a quick and dirty rendering for an as-near-as-damn-but-not-quite 'exact' sample of what the music sounded like pre[tisdu].

Realign the tracks as extracted to your hard drive by placing 5/100ths of a second silence at the start of the left channel. Amplify the left channel by 130% to rebalance volume output per channel.

Alternatively, copy the entire right channel and paste it into the left channel, thereby replacing the signal already there, and you'll be back to where the original mono boot was.

You can also create a temporarily un[tisdu]'d disc for the following use -

4) Editing a Flawed [tisdu] Set.

If you want to remove sound flaws from a [tisdu] set, I have found they edit more 'cleanly' in a temporary non-[tisdu] state, because sound flaws are usually consistent across both channels originally, not 5/100ths of a second apart across both channels as they are after [tisdu].

Extract the music to your hard drive as stereo, realign the tracks as described above to un[tisdu], do your edits on the now aligned left and right channels, and then, re[tisdu].