Compressors that Best maintain Stereo Image and Depth...?

VST, AU, etc. plug-in Virtual Effects discussion
SoundPorn
KVRist
337 posts since 24 Jul, 2018

Post Thu Jan 10, 2019 6:46 pm

Read this amazing thread recently with Fabian from TDR talking about the stereo image of compressors.
I never actually gave it too much thought until recently i was making this shepard tone droning soundscape sound using layers of special spatial effects that created this crazy detailed 3d soundscape.
But i noticed certain compressors just seem to completely flatten the image, in fact most did some extent with the same gain reduction applied.
But others specifically Waves H Comp, Accustica Tan, Garreckon eaComp87, even Firefly from Soundspot kept the spatial imaging.

So have others noticed this and what other compressors keep the spatial imaging what setting can help this too?

User avatar
Niowiad
KVRist
292 posts since 25 Jan, 2017

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Thu Jan 10, 2019 8:52 pm

Besides unlinking channels when the plugin has the dedicated feature, or using two mono plugins when that feature is not available, I dont know any other method.

I'd be interested in other people's take on this as well, eventually.

heavymetalmixer
KVRist
304 posts since 8 Jan, 2017

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Thu Jan 10, 2019 9:01 pm

Compressors as any other processors with non-linearities produce distortion, and distortion adds high-end, hence why usually compression makes a track sound wider (unless you set a Release slow enough to make the track sound dark).

I love how TDR Kotelnikov gives you the freedom regarding how much of the "anti-phase" content is detected in the compressor, though I preffer to always set it to 100% so it's like a classic linked compressor.

User avatar
Tp3
KVRAF
2141 posts since 8 Feb, 2007

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 7:37 am

Put a MS processor before the compressor and gently crank the side info.

It may replenish the lost info from the sides.
Professional technicians are assessed by the abilities they possess.
Amateur technicians are assessed by the tools they possess - and the amount of those tools, with an obvious preference to the latest hyped ones.
(Gabe Dumbbell)

No_Use
KVRAF
2332 posts since 13 Mar, 2004

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 7:53 am

Niowiad wrote:
Thu Jan 10, 2019 8:52 pm
Besides unlinking channels when the plugin has the dedicated feature, or using two mono plugins when that feature is not available, I dont know any other method.
Hm I'd think unlinking (or using two mono compressors) is rather contraproductive to maintain stereo image.
If you use separate, unlinked compressors for the two channels, then if one compressor reacts to a peak that the other doesn't see, the stereo image will pull towards the uncompressed side, and your listeners will start to feel very sea-sick!
https://www.soundonsound.com/sound-advi ... reo-source

User avatar
Niowiad
KVRist
292 posts since 25 Jan, 2017

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 11:04 am

No_Use wrote:
Fri Jan 11, 2019 7:53 am
Niowiad wrote:
Thu Jan 10, 2019 8:52 pm
Besides unlinking channels when the plugin has the dedicated feature, or using two mono plugins when that feature is not available, I dont know any other method.
Hm I'd think unlinking (or using two mono compressors) is rather contraproductive to maintain stereo image.
If you use separate, unlinked compressors for the two channels, then if one compressor reacts to a peak that the other doesn't see, the stereo image will pull towards the uncompressed side, and your listeners will start to feel very sea-sick!
https://www.soundonsound.com/sound-advi ... reo-source
There seem to be quite opposite school of thoughts about the subject.
And I've actually been quite suprised of how much something considered good for stereo image by some people, is considered bad by others (and vice versa).
I also remember reading an old gearslutz thread about this topic, with completely opposite opinions on the matter.

On one side, as it says in that SOS article, the separate amount of compression is seen as a bad thing as it shifts the L-R balance too much, on the other side you get top mix engineers such as Scheps or especially CLA who thinks the separate treatment of L and R is exactly what's good for stereo image and instead it's bad if both channels are being put under the same detector, resulting in one channel getting compressed on behalf of the other.

Minute 00:45
https://www.youtube.com/watch?v=Z0eqw_3cY2A

Minute 05:00
https://www.youtube.com/watch?v=yZ5ODieH4UE

As far as I've been able to hear first hand, I tend to gravitate more towards the unlinked, although I don't see it as a rule set in stone (pretty much as CLA seems to put it). Sometimes I like it, sometimes instead I feel as it doesn't really make a substantial difference, of course it depends on the involved amount of gain reduction.

Scheps was actually talking about parallel compression, but it sounds like he's talking about compression on stereo sources in general.
CLA goes unlinked even on the 2bus.

jochicago
KVRist
247 posts since 26 Feb, 2018

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 11:41 am

I'm saying this from my own understanding, I think CLA wants a nice even rendition of the instruments and he feels that if you don't unlink the L/R then the side that has a bit more volume drives the other side even though that other side didn't need compression, and viceversa. So in order to have the best evenness, he unlinks the compressors so they have more freedom to make channel-independent compression decisions instead of robotically pushing down on both ends when 1 of them crosses the threshold.

I never quite understood the real-case scenario, particularly in the LCR world that most of his rock music is in. If your bass is squarely down the center, then under what situation is the L going to be louder than the R that it would need unlinking the compressor? Same for the guitars panned 100% L, if there's nothing going on on the R channel, why unlink?

it makes sense to unlink if you are using a reverb send that is panned opposite of the guitar. You may pan that reverb 50% right, so now you have strong reverb information in the R channel and weak info in the L channel, so perhaps then if you put a ducking comp on that send you may want to unlink the stereo so that the compressor grips harder on the R data that is higher volume without compressing the L data that has lower volume. But this is not something I've heard CLA say, just my best guest at where this stuff would make sense. Perhaps he means all of this from a general view point: If things are hard-center than it doesn't matter if you unlink or not, but when things are partially panned or they move around in the stereo field then it is essential that you unlink. So as a result he just unlinks all the time to keep things simple. (Not exactly his words, my guess).

With Scheps is different and clearer (to me). He says he likes to keep one aggressively compressed send (that he will later blend into the mix), and he sends multiple tracks there. He likes how it sounds when multiple instruments are sharing the grip of the compressor. But that means that he'll send many tracks in there that may be panned every which way. So he unlinks the compressor on that send because the material in there is varied so he wants to allow the compressor to maintain an even grip on the channels independently.



RE: Preserving the stereo image
If the stereo imaging is perfect and you wish to preserve it, would it make sense to compress in M/S mode as to apply the grip to the Middle info and ignore the Sides?

sinkmusic
KVRAF
6171 posts since 28 Apr, 2004 from france

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 12:09 pm

BCA Dynamics can go very deep when you need to manage the way your compressor will affect the stereo image
https://www.bluecataudio.com/Products/Product_Dynamics/
Image

User avatar
Niowiad
KVRist
292 posts since 25 Jan, 2017

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 1:15 pm

jochicago wrote:
Fri Jan 11, 2019 11:41 am
Perhaps he means all of this from a general view point: If things are hard-center than it doesn't matter if you unlink or not, but when things are partially panned or they move around in the stereo field then it is essential that you unlink. So as a result he just unlinks all the time to keep things simple. (Not exactly his words, my guess).
Yes CLA doesn't explicitly say he's referring to stereo sources only, but I'd guess that's the only explanation.
A bass mono source at the center has the same stuff going on both channels so linked or unlinked it's the same, and any hard-panned source doesn't have stuff going on in the opposite channel so linked or unlinked it's the same.
Then instead if he takes e.g. the guitars as a group with different sources hard-panned left and right, or the drum bus, or the very mixbus, that's when unlinked has an effect.

About Scheps, he was talking about his "rear bus" technique, which revolves around parallel compression. Although, when he said "I love stereo compressing things with the compressors unlinked" it kind of makes me guess he's talking about (stereo) compression in general, not just as rear bus.

No_Use
KVRAF
2332 posts since 13 Mar, 2004

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 2:17 pm

Niowiad wrote:
Fri Jan 11, 2019 11:04 am
No_Use wrote:
Fri Jan 11, 2019 7:53 am
Niowiad wrote:
Thu Jan 10, 2019 8:52 pm
Besides unlinking channels when the plugin has the dedicated feature, or using two mono plugins when that feature is not available, I dont know any other method.
Hm I'd think unlinking (or using two mono compressors) is rather contraproductive to maintain stereo image.
If you use separate, unlinked compressors for the two channels, then if one compressor reacts to a peak that the other doesn't see, the stereo image will pull towards the uncompressed side, and your listeners will start to feel very sea-sick!
https://www.soundonsound.com/sound-advi ... reo-source
There seem to be quite opposite school of thoughts about the subject.
And I've actually been quite suprised of how much something considered good for stereo image by some people, is considered bad by others (and vice versa).
I also remember reading an old gearslutz thread about this topic, with completely opposite opinions on the matter.

On one side, as it says in that SOS article, the separate amount of compression is seen as a bad thing as it shifts the L-R balance too much, on the other side you get top mix engineers such as Scheps or especially CLA who thinks the separate treatment of L and R is exactly what's good for stereo image and instead it's bad if both channels are being put under the same detector, resulting in one channel getting compressed on behalf of the other.

Minute 00:45
https://www.youtube.com/watch?v=Z0eqw_3cY2A

Minute 05:00
https://www.youtube.com/watch?v=yZ5ODieH4UE

As far as I've been able to hear first hand, I tend to gravitate more towards the unlinked, although I don't see it as a rule set in stone (pretty much as CLA seems to put it). Sometimes I like it, sometimes instead I feel as it doesn't really make a substantial difference, of course it depends on the involved amount of gain reduction.

Scheps was actually talking about parallel compression, but it sounds like he's talking about compression on stereo sources in general.
CLA goes unlinked even on the 2bus.
The info / opinions in the videos are news to me (I always thought unlink - screw stereo image as said above), thanks for linking them (no pun intended :D).
Last edited by No_Use on Fri Jan 11, 2019 2:20 pm, edited 1 time in total.

No_Use
KVRAF
2332 posts since 13 Mar, 2004

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 2:19 pm

doublepost, sorry

Spin Boyz
KVRist
385 posts since 1 Jul, 2007

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 3:06 pm

Unlinking will skew the stereo image. Using it unlinked on the parallel bus won’t matter that much because you’re blending it in.
Last edited by Spin Boyz on Fri Jan 11, 2019 7:17 pm, edited 1 time in total.

SoundPorn
KVRist
337 posts since 24 Jul, 2018

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 5:10 pm

Yes this is exaclty what I want a push and pull between between speakers, get seasick ,please do, feel the motion, sound is swirling around you in every direction, you're engulfed.



quote=No_Use post_id=7281419 time=1547222014 user_id=16800]
Niowiad wrote:
Thu Jan 10, 2019 8:52 pm
Besides unlinking channels when the plugin has the dedicated feature, or using two mono plugins when that feature is not available, I dont know any other method.
Hm I'd think unlinking (or using two mono compressors) is rather contraproductive to maintain stereo image.
If you use separate, unlinked compressors for the two channels, then if one compressor reacts to a peak that the other doesn't see, the stereo image will pull towards the uncompressed side, and your listeners will start to feel very sea-sick!
https://www.soundonsound.com/sound-advi ... reo-source
[/quote]

SoundPorn
KVRist
337 posts since 24 Jul, 2018

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 5:15 pm

And I do use alot of mid side compressing as well as multi band mid side panning, the problem is keep that space relation.

Now I'm kinda talking too extreme examples when I'm in sound design mode. I wouldn't want to mix a whole track like that I would layer these sounds in.

But somebody mentioned phase and that may be one of the biggest differences is how different compressors handle phase.

User avatar
V0RT3X
KVRAF
7339 posts since 4 Jul, 2012 from Canada

Re: Compressors that Best maintain Stereo Image and Depth...?

Post Fri Jan 11, 2019 5:22 pm

Bookmarked this post

Return to “Effects”