Waveform start points for proper timing ?

  • Thread starter Thread starter kerriobrown
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K

kerriobrown

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Hi,

I've asked this elsewhere but never get an answer, yet it seems like it would be a common question.

I will often re-align (tighten-up) guitar audio to sit on the beats using either Cubase or Melodyne. Waveforms, however, typically have an attack where the largest amplitude is not at the beginning for the note (e.g. chord etc.).

Is there a psychoacoustic rule for where upon the waveform should be the beginning of the given note? Melodyne has an automatic 'quantize time' function but it seems to me to put the earliest part of the note on the beat, so I always thing my notes are a tad late. If I were to guess, I'd put the place of largest amplitude on the beat. I can see other theories too though, such as half-way b/t the beginning and highest amp (time-wise or amplitude-wise), or the point where the slope is no longer increasing etc.

To some this may be overly picky, but I have to tighten things up anyway, so it would actually save me time to know where to put things a priori. In fact, I am currently using a best fit approach b/t all of the methods described above which makes it sound tight enough but takes a while to eyeball.

Thanks!
K
 
well let me expose a never before heard theory in audio production philosophy: different types of instruments have different types of attack :cool:


On a serious note, when it comes to cutting at the best point within a wavefile, you cut on at the zero crossing point. The zero crossing point is simply the part of the waveform that intersects right at the centerline of your audio file just before the attack.You cut here to prevent pops and clicks, even if you're going to crossfade these points later.


Obviously, a guitar's attack consists of the strum and peak created by the release of the strum, so without that strum leading up to the peak, the guitar stops being a guitar. Every instrument has to account for Attack, Hold, Release and Decay. Just like in midi.



In terms of the philosophy in editing, you have to recognize that all wave forms have different attack and release times. I can see where you want to create really tight tracks, but it's important never to cut off the natural attack of an instrument, because doing so could make it sound painfully unnatural. Unless that's part of what you're going for.

There are other ways to go about it. You can always use dynamic affects to shape the attack and release of your track to fit the groove.

Actually, if you understand how sidchaining works, you don't really have to edit much at all. For example, you can trigger compressors on a guitar with the kick, creating a time based punch that sits well in the mix. They do this alot in dance and electronic types of music.

There are units dedicated to envelope shaping as well. Waves makes a Transform plug in that works well. SPL makes a very popular Transient Designer unit that goes well with drums, but also can be used on anything.

A surgical approach is to simply create or draw fade ins to your tracks...
 
try listening to it. I've found that using your ears when working with audio does wonders.
 
If you sat in a room surrounded by instruments playing a song, it would probably sound fine and natural "as is" without anyone lining up the attack times for you. The fact that our ears can discern all of those different subtleties is part of what makes music embellishing and interesting.

As long as the musicians have a good enough sense of timing to hold the song together, then I say leave it alone. Enjoy it as being natural.

"Tightness" only feels good in...ah, oops, (never mind.) :D
 
ez_willis said:
try listening to it. I've found that using your ears when working with audio does wonders.
Click to expand...

:D


Yes...it's all a matter of feel, and not some absolute position...and only your ears can decide what sounds/feels best.
icon14.gif
 
You know you could go further than that right? Why just line up the guitar? You should use the hitpoints feature or elastic audio and align ALL the parts to the grid. That way you'll have a nice mixdown where everything lines up perfectly to the grid.

This way, nobody has to practice their parts, or use their ears, and will still sound GRRREAT! OK, may not great, but PERFECT!!! Yeah, perfection is good.

We need more robots. :p
 
kerriobrown said:
Hi,

I will often re-align (tighten-up) guitar audio to sit on the beats using either Cubase or Melodyne. Waveforms, however, typically have an attack where the largest amplitude is not at the beginning for the note (e.g. chord etc.).

Is there a psychoacoustic rule for where upon the waveform should be the beginning of the given note?
K
Click to expand...

I think what you might be seeing is the transient of the waveform which is the very earliest part of the attack, in which the waveform makes its initial rise from -∞- (infinity, or silence) to the attack level. The example in which is the transient is most easily seen is the kick drum.

Psychoacousticly speaking, the amount of time the transient takes to rise is to small for us to perceive the transient alone.

Where in the waveform you chose to make your edits doesn't matter near as much as being consistent about it. Zero crossings are by far the best point but all it does is help you avoid clicks, and sometimes it just does not work out. If you are sloppy with the edit points the track will likely sound a bit floppy time wise, so to speak.

Cheers!
 
Let me start off saying this is a wonderful forum! I can't believe all the replies already.

...you cut on at the zero crossing point. The zero crossing point is simply the part of the waveform that intersects right at the centerline of your audio file just before the attack

I'm not actually cutting anything, just shifting and stretching stuff mostly using Melodyne. In the rare times I do have to cut something, Melodyne automatically works out the pops and clicks. In Cubase I just use the crossfades. But in terms of the nature of the sound, I always keep the attacks (i.e. I don't need to remove them or change there speeds), I just want to know where to place them.

For those who suggest listening I absolutely agree and my final edits will be ears only. I'm thinking on the 1st go around that using my eyes and having a simple rule to follow can be more temporally efficient though. Moreover, I've got a lot of takes to sift through and ear fatigue sets in fast. Eventually, I start psyching myself out and end up changing everything later. I do keep the originals just in case.

You know you could go further than that right? Why just line up the guitar?

My bass and drums are from programs so I'm OK there. Vox I may tighten a little but I think naturalness is pretty key here.

You should use the hitpoints feature or elastic audio and align ALL the parts to the grid.

Do you know a good program for this? Melodyne does a great job at not degrading stretched and shift audio IMO, but as I said the auto quantize time seems to align right where the attach begins which seems to late to me.

Zero crossings are by far the best point but all it does is help you avoid clicks, and sometimes it just does not work out.

I'm a little confused about the zero-point crossing still. What is zero, here? LeeRosario above said the centerline right before the attack but I can't see what is meant by the center line? Center in terms of amplitude or time? Does right before the attack mean when the played note technically begins? If so, are you saying this is where the note should align with the beat? Then Melodyne is doing what should be but I felt like the notes were coming in late.


I think the consistency idea make a lot of sense now. As I was reading through the replies I realized that my bass and drums may be sampled, but they have there own waveforms and ultimately I'll be aligning to these not my Cubase metronome click. Oddly enough, the bass and drum waveforms seem even later on the beat than Meloyne's preference. But if I just stay consistent, all I'll have to do is line up the file to the bass and drum samples one time once I'm done and then check w/ my ears what my looks good to my eyes.

Thanks again!!!
Kerry
 
For the 1000s of $ and hours people spend on infinitesimal improvements in audio quality, I'm a little surprised at the repulsion at tightening rhythms. It's mostly about synchronizing all of the instruments. But I am not solely relying on visual placement. My ears make the final decision and if the groove feels lost, I'd leave it as is, but so far my experience is that it only sounds better.

I do admit though, that I am somewhat OCD and there may be a placebo effect to having everything in its "correct" place.

Does anybody have examples of songs they've mixed that lost their character due to rhythm fixes (my current song is rock style w/ lots of 1/8 note palm muting at 145 bpm)? I would really appreciate hearing them. It may help to ease my obsessive concerns and fix my ears, which would save me a lot of time. I'm not referring to obvious extremes such as machine gun drum rolls.

Thanks,
K
 
Wanting to "tighten up" the rhythm is not necessarily a bad thing in itself.
Doing it in some assembly line, auto-robotic fashion might make things tighter, but it may also ruin the entire feel of the song. It can end up sounding like a MIDI sequence with "auto quantize" turned on.
I like to nudge things around...but I would first listen to the song, and only nudge where it's blatantly off the beat in a bad way.

I dunno’...are you the guitar player on the recorded tracks? When you play, do you always TRY to hit the beat with every note??? It can be as small as a couple of milliseconds...but that could the difference between a nice groove the playing and that rigid, sequenced-like perfection.
And I'm someone who records with click track...but there is still a lot of room to "work around" the beat and still be on time, and sounding tight.

Another thing to consider...when you line up several notes from several tracks exactly on the beat...you will start to alter the overall sound.
If the attack of your guitar note is j-u-s-t ahead of the snare hit...their combined sound will be noticeably different than when both note and snare hit are exactly on top of each other, with their attacks perfectly lined up.
So proceed with caution...'cuz not only can you screw up the feel if you make it too perfect...you can also screw up the sound too.

When I nudge things around, I make sure to do it with a certain amount of randomness...so DON'T use the exact same point of your wave forms as your guide for every note/beat. Vary it randomly…be a bit loose about it. But then...maybe of you just play tightly with the beat when you record, you will end up with groove, good sound...and natural randomness. ;)
And this is coming form someone who's been down that anal "gotta make everything perfect path".
It's a sickness...don't let it get you! :D

There’s a term that comes to mind here that you might want to consider… “as it falls”.
icon14.gif
 
kerriobrown said:
You know you could go further than that right? Why just line up the guitar?

My bass and drums are from programs so I'm OK there. Vox I may tighten a little but I think naturalness is pretty key here.

You should use the hitpoints feature or elastic audio and align ALL the parts to the grid.

Do you know a good program for this? Melodyne does a great job at not degrading stretched and shift audio IMO, but as I said the auto quantize time seems to align right where the attach begins which seems to late to me.
Click to expand...

Hmmm, I hate forums, because something gets lost there...

OK, in case you missed it, I was being sarcastic.

However, the program I was referring to was Cubase. You said you use Cubase, which has both hitpoints feature and the latest versions have the "elastic audio" feature...

But for god's sake man, don't do what I "suggested".

Learn to play "in the pocket" and learn how to play tight. There is no substitute for practicing!

I mean, seriously... Listen to Metallica's "Ride the Lightening". Do you think they nudged and quantized all those crazy guitar parts?
 
Thanks Miroslav, you convinced to try a different approach. I was tightening up everything before choosing the final takes, since I figured after timing editing could possibly change what ended up being the best takes.

But it would be impossible to compare all of these takes to their original non-altered counterparts to see if I lost some feel and you've convinced that both feel and sound via synchrony could change.

So instead I'm going to choose my best takes now and try at least a few 'quantized' samples for A/B comparison. That will be more manageable.

One thing I have to consider is that I recorded guitar with just a metronome, so how well it falls in w/ the bass and drums may not be musically considered. If so, my probability of getting the best synchrony sound-wise may be just as low whether I move things around or not.

I wish I'd posted this 3 weeks ago when I started this whole process of shifting stuff. I'd guess I wasted 60 hours or so. That may seem crazy (OK, it is) but I don't mind losing month of life for a song that will last me a lifetime.
 
OK, in case you missed it, I was being sarcastic.

I got it after realizing you had posted the comment above it, but I forgot to take out my reply.

I've played w/ a metronome for years now, sometimes for 10 hours a day. I have always been very strict w/ this. Maybe it didn't take as well as I'd like, though I got my first chance to tour a professional studio the other day and the work they were doing looked as spliced as mine, so I may be OK there.

The hard part, which I'm sure is the norm here, is trying to do everything myself. I turn off my AC to get rid of hum, move from chair, to amp, to tuner, to headphones, to preamp, to space bar, all with my guitar strapped on and pick in hand. The actual recording process feels like physical labor. More important, I alone have to decide how tight my playing was while actually playing it as opposed to have a professional monitoring all of my takes. Mixing is a lot more relaxed so I maybe rush a little to get there, especially if I can't tell the difference between good and great while performing anyway. I'm not whining just explaining why I lean to fixing it in the mix.

Good point w/ Metallica. Modern metal in the same vein can often sound a little clinical, but I'm not convinced it's just that the songs aren't as good.
 
kerriobrown said:
Because it sounds better.
Click to expand...
But why did it sound bad to begin with?

I mean, is it a performance issue? Or is it simply trying to align tracks in a project where you don't have a reference time code?

If it's a performance issue, then the problem is best fixed in the performance.

If it's a track alignment thing, then what you can do is stick a slate marker (hand clap, drumstick slap, etc.) in the pre-roll of the rhythm track and then copy that over to your guitar tracls before you record them. Then when you nee dtoimport the tracks into another project, just line up the slate markers and you're cooking with gas.

I might also point out - as I now see that miro has already done - that getting things on the beat is not always the most musical way to go. The best musicians know how to affect the song groove by playing either slightly ahead or behind the beat.

G.
 
kerriobrown said:
One thing I have to consider is that I recorded guitar with just a metronome, so how well it falls in w/ the bass and drums may not be musically considered. If so, my probability of getting the best synchrony sound-wise may be just as low whether I move things around or not.
Click to expand...

While playing to the metronome will get you to play more or less evently (tempo-wise), that doesn't mean what you played is going to work with the rest of the stuff that's going on.

Is there any reason why you are not playing to the other pre-recorded stuff to begin with? There is more to good sounding music and individual parts than just being in time. How about feel, phrasing, making sure what you play fits with the rest of the ensemble not just tempo-wise, but also conveys the same emotion, etc.

Playing to the metronome only is pretty much as useless as lining up your guitar parts with the eye. In the end everything will sound like perfectly lined up crap.
 
kerriobrown said:
One thing I have to consider is that I recorded guitar with just a metronome, so how well it falls in w/ the bass and drums may not be musically considered. If so, my probability of getting the best synchrony sound-wise may be just as low whether I move things around or not.
Click to expand...

So then record your guitar parts after you have some of the rhythm tracks already down.

I'll often track with some sort of SOP...but if I ever find that something just doesn't lay out very well with the other tracks...maybe becuase I recorded it at the wrong time, and didn't have enough "information" to play against...I'll just re-record the track(s).
After awhile, you will find and SOP that works for you.

If you can kinda' hear the finished song in your head (before it's all finished)...it makes it easier to do the track-by-track recording, but if you like to just focus on single tracks, and then see what kind of song/mix you end up with later...then you may need to go back at times and re-recod stuff if it's not working.
 
SouthSIDE Glen said:
If it's a performance issue, then the problem is best fixed in the performance.
Click to expand...

HUGE +1 here. Maybe this is just me being a traditionalist because I'm a guitarist more than an engineer, but if your finished tracks need some sort of quantization to sound in time, then they're not finished takes. Digital manipulation is no replacement for a good performance.
 
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