* Here's what I need to do: 

Using multiple takes of a single song performance from a field
recording session (of pipe organ music, as it happens), create a final
demo recording of that song that's as (artificially) perfect as it can
be. As in, "oh, the performer really screwed up that riff in Take 4
but the rest of the take was brilliant -- let's replace those 3
seconds with the same riff from Take 7 where he nailed it." The
portion of the Take 4 wave file containing the bad riff is overwritten
with the pasted-in copy of the same, correctly-played riff from take
7. That sort of thing.

* Here's what editing software I have: 

CoolEdit 2000, Sound Forge XP and an old copy of Red Roaster
(basically a 2-track version of old Samplitude) that I could scare up
and reinstall.

* Here's what I need help with:

The essential problem, of course, is that "punching in" with material
from another take needs to be imperceptible, so I've played around
with using a Mix Pasting operation (in Cool Edit 2000) with a bit of
crossfade, with mixed results (heh). Sometimes it seems to work, other
times the transitions are quite audible.

Am I on the right track here? What's the approach to doing this kind
of edit? i.e., I find a place in the music where notes are being held
or otherwise not changing momentarily, get the wave file cued up as to
exactly where and how long I want to overwise insert the external
clip, then I prepare my insertion clip to be the proper length and
copy it to the system clipboard...but THEN WHAT? What's the best way
to trick the listener into thinking that the performer played the
piece perfectly in just one take?

The key issue here is that I'm not just inserting a clip from another
take, but I need to actually overwrite a short passage of music with
the same passage from another take.  Is this basically a butt-splice
operation where you then try really hard to smooth the transition (if
so, how?) or do I want to overlap the same sound in both the active
audio file and the clip I'm pasting in (if so, how?).  In my current
project, the pipe organ music has plenty of static moments where the
sound is briefly constant, so there are sufficient places where I
could try to blend in in another take by overlapping the audio for the
same held chord....but I'm far from clear about whether this what I
want to do and how I should approach it.

I posted an earlier question about crossfades, and what I learned
there (which was plenty) leads me to believe that this tool might be
applicable if in fact one does need to try to overlap the tail of one
passage with the lead-in of the clip you're pasting in.

Hello again eric_boston,

I think we are both beginning to understand a little better what it is
you desire to do. As an aside, pipe organ is particulalry challenging
to record as it can produce the lowest audible (and below audible)
tones of any instrument short of a synthesizer. Microphone choices and
mic placement as well as the reverberation quality of the room will
greatly effect the outcome of your recordings. I mention this to place
a little emphasis on monitoring the bottom end a little more carefully
than one might normally while doing your assembly editing.

In other words, depending on the performance, the mics, the room and
the micing technique, there may be bottom end that will not be obvious
on almost any headphones or a casually setup monitor speaker system. A
subwoofer may be a big asset here, if properly calibrated in your
monitor system. Just a head's up, and something I probably would not
have mentioned if your performance material was a jazz quartet or club
band.

With insert editing, or assembling a tune from multiple takes, you
have several things to consider:

1. Level matching if they happen to differ in different takes
2. Pitch, if that can be a problem from a wind instrument, changed mic
placment or other variable
3. Tempo - different takes may or may not have slightly different
speeds and tempos

Tha above assumes that all takes were done in the same room, same
mics, no major changes. If that is not true, then you also have to
consider things such as the reverberation quality of the different
rooms or as a result of changed mic placements. For the sake of this
discussion, I am going to assume that pitch, tempo and reverb are all
well matched and we are just trying to learn how to make
imperceptible, or nearly imperceptible insert edits.


I took a look over at the CoolEdit website and their forums (
http://forums.syntrillium.com/forum.asp?FORUM_ID=15&CAT_ID=4&Forum_Title=Cool+Edit
) just to be sure that the software you have has the capabilities to
perform your desired tasks. It seems that it does. One user had noted
that when he removed sections from his tunes, it was obvious where
things had been cut. Another user suggested:

"It is possible, using Cooledit, to lengthen, shorten, rearrange and
otherwise alter a song in a seamless way if you fully understand how
that song is put together. If your edit points are precise and clean,
then the result will be seamless. And if you are using multi-track,
then the use of crossfades can also make things seamless."

So this begins to answer the how of your insert question. 

The thread continues with another forum member's reply:

"Your best friends for this task will be...your eyes, ears, the
"shift" key, the zoom buttons, and that little sideways 8 beside the
play button for "loop play".

Make your selection (part of the wave you want to remove,edit,ect..),
now hold down the shift key to adjust you selection size. Then use the
zoom keys to zoom in to visually adjust your selection for accuracy.
This comes in handy at the beginning and end of your selection.

Use the sideways "8" by the play button to play your selection over
and over and adjust your selection (with shift key) until you get it
sounding right.

TIP: You'll find that using the peaks (kick drum/bass) in your wave
file as reference points will make things a lot easier. Just zoom in
and adjust your selection as close as possible to the peak, so when
you paste back (whatever) it makes it a lot easier to remember where
to paste.

I do it all the time seamlessly ;)"

This really is key. The actual points of entry and exit into a
punch-in will determine how easily an edit can be perceived. Using
transients (if available) as opposed to sustained tones will aid. If
only sustained tones are available, then a crossfade between track
(takes) will probably be a better choice. As amatter of fact, this
thread (http://forums.syntrillium.com/topic.asp?TOPIC_ID=6362&FORUM_ID=15&CAT_ID=4&Topic_Title=editing+advice&Forum_Title=Cool+Edit
) asks the question almost identically that you do:

"...with CoolEditPro, what do you think is the best way to go about
editing a solo piano performance?

Let's say I have 3 takes of a particular piece of music and I want to
splice certain parts of one take into certain parts of another... In
the old software I was using, I had each take as a separate track, and
I used volume controls and cross-fading to achieve the splices. Should
I do this in CEP, or should I use one track and cut-and-paste the
other files into it? I know that when I was working with a recording
engineer, he used protools and I seem to remember something about
adding each segment used to a cue sheet?"

Users answer:

"Well this largely depends on the recorded audio... I would try both
methods you mention although I'd start by cutting and pasting from one
to the other. Make sure all splices are done at zero crossing points;
and preferably on 'hits' in the audio. I mean, try to splice the audio
on a point where you hit a new chord on the piano or something - this
prevents you from audible clicks and pops.

But like I said this is trial and error... "

So, as you can see, both are acceptible and used techniques for insert
editing. My personal choice is, as I mentioned, to choose my technique
depending on the amount or lack of transients in the music where I
need to insert.

Specifically to CoolEdit, a user notes:

"I'm assuming that you're going through with the score to figure out
where you want to make each edit. Using the cue marker to precisely
mark an edit point (and always cut as close as you can get to the
start of the next note without clipping it) on each take you could
then use the multitrack to audition alternative versions at this edit
point. Snap to cues will help with cutting in the multitrack after
marking in the edit window, and snap to waves will help put everything
together precisely."

He continues:

"Unless there's an audible click I'd try and avoid using cross-fades -
actually if there's an audioble click I'd go back and redo the ins and
outs of the clips. The strong impulse of a new note or chord
immediately after the edit point should mask the edit to the point of
inaudibility, and unless you've made a major error just prior to the
drop-in point the fading reverb of previous notes should merge
seamlessly."

While yet another member adds:

"Using the multitrack view is definitely the way to go - You can line
up the waveforms until they match up exactly, thus ensuring an
accurate splice. Every cut is different and choosing a good location
for a cut will depend on the musical context of the piece. I find
using the cross fade lines extremely useful in obtaining a clean,
smooth transition (a cross fade can be extremely quick - almost to the
point of being a complete cut) as it just takes the 'edge' off the
cut. If, for instance, on one take, you played a chord before a splice
point too soft or loud, the reverb won't match up after the cut -
experiment with the cross fade points until you obtain a seamless
join."

This would be a very useful thread for you to read in total, and also
an excellent place to asks further questions on the use of CoolEdit
and digital audio software in general.

Thsi thread, "Placemarks when editing waves files?" at
http://forums.syntrillium.com/topic.asp?TOPIC_ID=6122&FORUM_ID=15&CAT_ID=4&Topic_Title=Placemarks+when+editing+waves+files%3F&Forum_Title=Cool+Edit
is also very appropriate for your questions. It details the use of the
cue list in CE.


I took a look over at Sonic Foundry http://www.sonicfoundry.com , to
see a bit more about Sound Forge, but did not notice Sound Forge XP.
If it is a previous version of Sound Forge 6.0, I'm sure it also has
all of the capability to perform the edit tasks you desire. I then
found the manual for Sound Forge XP 4.5 available online in pdf format
at their site here: http://www.sonicfoundry.com/download/step2.asp?DID=194

There is also an online tutorial for basic editing with Sound Forge
here: http://www.sonicfoundry.com/tutorials/English/SoundForgeBasics/start.htm

As a matter of fact, there are numerous online multimedia tutorials at
Sonic Foundry here: http://www.sonicfoundry.com/tutorials/default.asp
. I'm sure some of these will be VERY helpful for you to master the
specific commands and techniques of this software package.

Lastly I took a look for Red Roaster. I found it here at
http://www.sekd.com/product_main/rr_info.htm . It seems like a very
useful and flexible mastering software package that will allow you to
polish and finish your final mixes. It is not for doing the insert
editing addressed by this question, but rather final assembly, table
of contents, index markers, dynamic control and the like. It seems to
get excellent reviews.

So, to sum up a bit, you seem to have all the tools you will need at
your disposal and just need a little experience and practice in basic
digital audio editing. Both butt splicing and crossfades will be
valuable tools in your arsenal depending on the current project's
audio content. Match you levels and pay a bit of attention to tempo,
pitch, frequency response and reverberation. Try to always enter an
edit on a transient and exit at the end of a reverb tail if at all
possible. Monitor on a quality audio setup where you are in the
nearfield of the soundfield and avoiding as much room interaction as
possible and experiment and practice as you will not lose you original
recordings with non-destructive editing.

As always, I'm happy to clarify any points above if needed, but I
think this will put you well on your way to your desired end result.

Best regards,

-=clouseau-ga=-

---

Request for Answer Clarification by eric_boston-ga on 03 Sep 2002 11:08 PDT

Thanks very much -- this is exactly the information I need.  I'm not
sure what transients are, and as they seem important to doing this
right, I'd appreciate a basic definition.

Other than that, this is very clear and will definiately get me
started on the right learning curve.  Half the battle is knowing what
the right question is!

Eric

---

Clarification of Answer by clouseau-ga on 03 Sep 2002 11:40 PDT

Hello again,

I'm very pleased that this is what you need and appreciate your
rating!

Transients are the initial attack of a sound and usually of very short
duration. For example, the pluck of an acoustic guitar string that
preceeds the sustained vibration after that intial attack. It can
often be 15dB or so hotter than the average signal and is the reason
that a high quality sound system requires lots of power for headroom
and clean reproduction with minimal distortion even when being played
back at moderate listening levels. The accurate reproduction of a
transient is also related to the slew rate of an amplifier, or its
ability to pass voltage quickly enough to represent that leading edge
of a square wave with accuracy.

If you look for these transients in your music- snare rim shot, guitar
pluck, kick drum etc. and use them to match your inserts carefully,
you should have success in assembling your music. In your case, they
will be a little less defined since your material is primarily pipe
organ with softer transient attacks.

An interesting paper on the Elements of Music Perception at Headwise -
http://www.headwize.com/tech/elemnts_tech.htm ,  notes the following
on transients:

"Attack transients occur when an instrument starts playing a note (for
example, the striking of a piano note). Decay transients are the
sounds of a note fading away. If these transients are removed (say,
edited out in a recording), the sound of the remaining steady note
loses its distinctiveness."

You might find this paper an interesting read.

Best of luck with your recording project and thanks once again for
your questions.

Regards,

-=clouseau-ga=-

Once again, great service.  Even gave some useful advice for a side
issue that I didn't ask about.