# Phase cancellation with string libraries



## Havoc911 (Mar 7, 2018)

I'm having a problem when writing for strings. There's no budget for live players on this song and everything must be samples. I've written the part, but now that I'm trying to mix it, there are audible phase issues. I have confirmed this with Voxengo SPAN. I've tried everything and the only thing that works is to predominately use the close mics (library is Cinematic Strings the first version). I've seen a lot of people who will use just the stage mics or a combination of close+stage to get things to sit back in the mix or sound big, so I think maybe there must be something else I'm doing (or not doing).

The part is pretty simple. Violin, viola, cello and bass, yet when I use only the stage mic, there is quite a bit of audible phase cancellation. This happens even when the reverb sends are muted and the release tails turned off.


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## Emmanuel Rousseau (Mar 7, 2018)

Phase cancellation issues can happen when more than one mic is used on the exact same source. If you're using just one microphone position you physically can't have phase issues.

What is exactly the problem here ? Are you sure you're not refering to "simple" frequency masking with some of the other tracks of your song ?


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## Scoremixer (Mar 8, 2018)

Somewhat sceptical... can you post an example?


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## MatFluor (Mar 8, 2018)

An Example would be beneficial, yeah.

Most developers have phase in their mind when preparing the mics, so you can freely mix them without worry. What can happen is e.g. if you try to double up strings, e.g. MAke Violins I and II unison using the identical patch and settings, or e.g. double up an ensemble with a section, where the ensemble is made up of this exact section patch as well (you get what I mean?).


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## RiffWraith (Mar 8, 2018)

Sounds like you are hearing double the op. What DAW are you using? Check your monitoring, and make sure you are not hearing the signal pre AND post (whatever). If you use Cubase, make sure the control room is off. If you use PTools, make sure direct monitoring is off. Make sure that no tracks in your DAW are record enabled, and check your sound card's control panel to see if you have any loopback settings turned on.

Cheers.


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## Havoc911 (Mar 8, 2018)

Thanks for all the suggestions. I plan on doing some more testing later today and I'll post an example when I can. 

I guess the sound of what's happening is similar to having a compressor with a really fast attack and release ducking the volume randomly. I threw on SPAN and saw the correlation was flipping negative a lot (almost to -1 at times). It correlates with the audio irregularities. This occurs with and without reverb, but it's not nearly as bad when using the close mics only.

I thought maybe this was a known issue with the older version of Cinematic Strings, as I have never used this library before.


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## Havoc911 (Mar 8, 2018)

OK, I've uploaded a bounce to soundcloud. Here's the link:



You can really hear it on the long notes. This is the stage mics only with no reverb turned on in CS or as an insert. The routing goes from the individual tracks to a string buss and then a submix before hitting the output in Cubase. There are no plugins in the chain with the exception of SPAN. No direct monitoring or control room monitors are being used.

Here is a video of what SPAN is doing during playback:



Thanks in advance for your advice!


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## RiffWraith (Mar 8, 2018)

I hear no phase cancellation in that ex.

Maybe someone else with Cinematic Strings can post an audio ex using the same MIDI and mic positions, to see if there is any inherent diff?


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## Havoc911 (Mar 8, 2018)

RiffWraith said:


> I hear no phase cancellation in that ex.
> 
> Maybe someone else with Cinematic Strings can post an audio ex using the same MIDI and mic positions, to see if there is any inherent diff?



Yeah, I'd be interested to see the comparison.


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## lumcas (Mar 8, 2018)

whitewasteland said:


> Phase cancellation issues can happen when more than one mic is used on the exact same source. If you're using just one microphone position you physically can't have phase issues.
> 
> What is exactly the problem here ? Are you sure you're not refering to "simple" frequency masking with some of the other tracks of your song ?



sorry, but one mic position usually consists of more than one mic (ORTF, spaced pair, decca tree). I've noticed that problem before too and not only with strings. Majority of developers basically don't try to be mono compatible anymore (yes, there are some exceptions).


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## germancomponist (Mar 8, 2018)

I would not spend my most precious, my lifetime, with something like that! Counting peas is boring!


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## chrisr (Mar 8, 2018)

lumcas said:


> Majority of developers basically don't try to be mono compatible anymore.



Yes I think this is what you're hearing.

I don't own either this library or the studio (CSS) follow-up but something I've noted about both is that they're seemingly _very_ wide... mono compatibility seems to be of much less importance nowadays, maybe justifiably...?


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## germancomponist (Mar 8, 2018)

chrisr said:


> Yes I think this is what you're hearing.
> 
> I don't own either this library or the studio (CSS) follow-up but something I've noted about both is that they're seemingly _very_ wide... mono compatibility seems to be of much less importance nowadays, maybe justifiably...?


Who hears mono? You? And if, why?
I remember, in the very past I did it, because radio stations told me to do this, but now I never do it again .... .


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## Piano Pete (Mar 8, 2018)

While you could argue there is some phasing going on, it really just sounds like sampled strings to me. Maybe try a different library or try to mask it if it is really bothering you--orchestration or extra audio processing? Depending on the project, you might not want to waste too much time trying to fix this in lieu of just getting it sent out the door.

--Edit-- Of course, I would talk with the developer to see if there is something wrong on their end, but I would not necessarily wait for a fix from them if there is. If that makes sense?

--Second Edit-- I know you commented that you do not have a budget for live players; however, this may be a case where you could grab a small string quartet and sweeten that up like a juicy fruit. The continuity from a live instrument may, or may not, be enough to distract the ear from whatever the samples are doing; the samples would then just be extra bulk and fiber. On the flip side, if you cant get the dubs to sit well with your samples, the whole thing will sound off.

If you happen to know some string players, grab a few bucks for them or take them out for drinks--depending on your relationship.

--Third Edit-- You could even just grab a violin (have them just play both lines in isolation), viola, celli, and possibly bass, but you could leave the latter out. I have had a lot of success doing this, but I am also lucky that I have a lot of players that I can utilize.


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## Havoc911 (Mar 8, 2018)

Piano Pete said:


> --Third Edit-- You could even just grab a violin (have them just play both lines in isolation), viola, celli, and possibly bass, but you could leave the latter out. I have had a lot of success doing this, but I am also lucky that I have a lot of players that I can utilize.



This area is quite rural and we don't have many string players floating about. That said, do you think it would be worth trying to layer some of the EW stuff on there to beef it up a bit? The guy I'm working with, and whose song it is, is willing to get a subscription if it might help.


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## Scoremixer (Mar 8, 2018)

Hard to tell through soundcloud compression, definitely some artifacts in the top end but it really just sounds like slightly naff sampled strings to me more than anything else. Don't worry about what your phase meter is telling you, it's perfectly common for phase meters to register negative correlation on certain notes in live rooms. 

Of course there's phase cancellation going on when you record live players in real rooms - every surface will reflect something back and interact with the direct sound, even if only capturing with one microphone. It's not apparent as 'phase' problems in live scenarios because every note does something different in the room... Sample that single note however, and map it across a keyboard and all of a sudden your ear starts to pick up on the phase and frequency relationships remaining constant and it sticks out as unnatural. One of the reasons why making good sample libraries is hard, and convolution reverbs can't replace real rooms! 

If you're struggling with it, then layering a couple of live players, or another sample library with a different vibe can help fill in the cracks.


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## chrisr (Mar 8, 2018)

germancomponist said:


> Who hears mono? You? And if, why?
> I remember, in the very past I did it, because radio stations told me to do this, but now I never do it again .... .


Well I have several dab radios around the house that play in mono, and many of digital stations actually broadcast in mono. In the uk bbc radio stations specify that all audio should be "mono compatible" which is admittedly quite a vague spec.

But the more important factor Gunther, as I'm sure your aware, is that when things get too wide they simply become dual mono, and the illusion of a stereo field is destroyed... or at least a hole is blown through the middle. So i think for those reasons it's still good to check this stuff.


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## germancomponist (Mar 8, 2018)

Maybe a good reminder, chrisr. I had totally forgot to do this because in my head there are many other things turning arround ... .


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## Piano Pete (Mar 8, 2018)

Honestly, for the price of EW's stuff, you cannot go wrong with having their samples in your arsenal. I still utilize a lot of their stuff. Look at it this way, for the price of a single year of CCloud, you get access to their entire catalogue for the price of a single library.


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## Havoc911 (Mar 8, 2018)

Thanks everyone for your input. We've decided on the EW CC to do some layering.


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## Piano Pete (Mar 8, 2018)

Dont be afraid to do some sculpting with eq to get the sounds you want! 

-Happy hunting.


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