What do summing extensions actually do?

[jakeru19]

I apologize if this has been covered before--I imagine there were extensive technical discussions about the summing extensions upon Luna's release--in which case if someone could kindly point me to the right thread, I'd be very grateful

I hope I won't come off too skeptical; I am a true fan of UA's work, believer in the superior quality of their products, and have purchased no less than 4 Apollo interfaces, an OX and most of the UAD plugin catalogue.

But... I cannot help that as I now dive into Luna I'm a little skeptical: How do these API/Neve summing extensions work? Moreover, are they different from applying a saturation-style plugin to the buss as one could in another DAW? I get that the summing extensions emulate specific summing amplifier circuits not modeled elsewhere. I mean, conceptually, are they different from regular "plugins" processing the output from the bus they are applied to? Is there processing being done on the source tracks? Is there some change to the way the source signals are summed?

I am no electrical engineer, and perhaps my failure to understand the science of analog summing leads me to incorrectly expect that there is more complexity to analog summing than the current Luna implementation. (I do not mean to invite a whole debate on analog vs. digital summing)

Some of the other types of 'extensions' i.e. 'tape' and 'console' seem like they are just new names for particular types of plugins/inserts, except that they have their own special place in the Luna GUI. And while I agree that having this integration with the DAW's layout affects our workflow, our creative decisions and is therefore worthwhile in creating an analog 'experience,' I feel I could (albeit less easily) recreate the same signal path sonically using the same UAD tape and console plugins in another DAW.

So I am wondering... are the summing extensions also like normal plugins in this regard, brushing on their color after the tracks have been summed, or is there deeper functionality. I plan to use the summing extensions regardless because they sound good and that's all that matters, but the tech-nerd in me still wants to know.

Rock on!

 

[Nyoak34]

I apologize if this has been covered before--I imagine there were extensive technical discussions about the summing extensions upon Luna's release--in which case if someone could kindly point me to the right thread, I'd be very grateful

I hope I won't come off too skeptical; I am a true fan of UA's work, believer in the superior quality of their products, and have purchased no less than 4 Apollo interfaces, an OX and most of the UAD plugin catalogue.

But... I cannot help that as I now dive into Luna I'm a little skeptical: How do these API/Neve summing extensions work? Moreover, are they different from applying a saturation-style plugin to the buss as one could in another DAW? I get that the summing extensions emulate specific summing amplifier circuits not modeled elsewhere. I mean, conceptually, are they different from regular "plugins" processing the output from the bus they are applied to? Is there processing being done on the source tracks? Is there some change to the way the source signals are summed?

I am no electrical engineer, and perhaps my failure to understand the science of analog summing leads me to incorrectly expect that there is more complexity to analog summing than the current Luna implementation. (I do not mean to invite a whole debate on analog vs. digital summing)

Some of the other types of 'extensions' i.e. 'tape' and 'console' seem like they are just new names for particular types of plugins/inserts, except that they have their own special place in the Luna GUI. And while I agree that having this integration with the DAW's layout affects our workflow, our creative decisions and is therefore worthwhile in creating an analog 'experience,' I feel I could (albeit less easily) recreate the same signal path sonically using the same UAD tape and console plugins in another DAW.

So I am wondering... are the summing extensions also like normal plugins in this regard, brushing on their color after the tracks have been summed, or is there deeper functionality. I plan to use the summing extensions regardless because they sound good and that's all that matters, but the tech-nerd in me still wants to know.

Rock on!

I suppose I'd just urge you to embrace the simplicity of it all and make some music. The summing is the special sauce for a lot of people - if you got another way, do it. The layout and workflow of Luna are the main factor for me. There are many combinations that will get you to a great mix... many plugins trying to add harmonics... many people mixing hybrid (though delay compensated hardware inserts would be really great, UA)...

You have to find tools that get the best result in the quickest manner... for you.

 

[hotspot]

It glues just like analog summing but in the box. With the help of overtones your sum will become richer and more dense.
There is other software out there that does kind of the same, such as Waves nls, which personally doesn't convince me as much and requires more effort than summing in Luna. It's just there right away, once you've used it in the mix, you won't want to do without it.
Many people swear by analog summing because that's exactly where it counts.
Others don't care.
For me, it's not worth the extra effort it takes to use analog summing in a meaningful way.
Nevertheless, I'm aware of the positive effect, so I'm grateful to be able to use it directly in Luna in an appropriate way.
My mixes sound better as a result.

 

[sws1]

It's most likely a combination of frequency specific saturation, widening, and/or cross talk.

 

[ndallago]

Great question, and well articulated. Have often wondered the same, and look forward to a response from UA for a better understanding.

 

[LesBrown]

In case it helps:

What is summing in audio mixing - Major Mixing

What is summing in audio mixing➤ Read the article by a professional engineer ♫ on the Major Mixing blog 🎹

majormixing.com

 

[Deif]

Great question, and well articulated. Have often wondered the same, and look forward to a response from UA for a better understanding.

They're not going to reveal the secrets but I agree with sws1 post

 

[Joe Porto]

I assumed they just simulate the summing amp. I didn’t think there was any channel interaction simulated in the summing itself.

 

[Nicolher]

They're not going to reveal the secrets but I agree with sws1 post

+1 on this
May I add that summing was one of the thing that made me a day one Luna user (although I ended up using it for almost 2 years without it, for financial reasons, but it was still great )
I‘ve recently gor a good deal on the neve summing and I just love it
Can’t wait for Neve console !

 

[hotspot]

I assumed they just simulate the summing amp. I didn’t think there was any channel interaction simulated in the summing itself.

If they simulate an analog summing amp, guess they introduce crosstalk as well. I can only guess, but for summation without crosstalk the sum in Luna does not seem transparent enough to me. I think that the high-energy low frequencies interact between the channels.

As for widening, I think it's more the psychoacoustic effect of a wider mix that occurs when saturating across the entire frequency band, especially in the highs, air range. I don't think they actively intrude on the panorama.
This effect can also be observed with the VSM, for example. Which is why you have to be careful that the cohesion of the mix doesn't suffer too much from the impression of a wide one.

It would be cool if UA could provide a few technical insights, Drew @UniversalAudio?

 

[UniversalAudio]

If they simulate an analog summing amp, guess they introduce crosstalk as well. I can only guess, but for summation without crosstalk the sum in Luna does not seem transparent enough to me. I think that the high-energy low frequencies interact between the channels.

As for widening, I think it's more the psychoacoustic effect of a wider mix that occurs when saturating across the entire frequency band, especially in the highs, air range. I don't think they actively intrude on the panorama.
This effect can also be observed with the VSM, for example. Which is why you have to be careful that the cohesion of the mix doesn't suffer too much from the impression of a wide one.

It would be cool if UA could provide a few technical insights, Drew @UniversalAudio?

We modeled the summing amps themselves. When combined with our channelstrips, you get a full path emulation.

Analog is nothing more than a collection of parts into circuits. There is no magic here, it's just physics. We do component level modeling that once connected into virtual circuits, behave like the real thing.

 

[hotspot]

behave like the real thing

Which includes x-talk?

 

[DanButsu]

Ah... I believe it's not crosstalk at all, but simply noise. See snapshot with no signal!!! Sorry for the confusion

 

[hotspot]

Thanks Dan for your efforts, very cool!
Is your graph weighted or is it the more energy on the lower side?
Which would confirm my assumption above.

edit: ah okay, good to know, thanks for cross checking

 

[UniversalAudio]

Which includes x-talk?

We only did tape crosstalk on the ATR 102, since it is a stereo unit. We have never done electronics crosstalk in any emulation, even emulations of stereo units. We can’t do meaningful crosstalk between channels along the lines of what you’re probably thinking, although there might be some very kludgy way to do it that makes it un-fun. We’d have to have hooks into the DAW.

By and large, users who really love what we do with realistic emulations (and actually worked in the purely analog era) don’t want certain analog artifacts; Electronics self-noise and crosstalk among them. I sure don't!!! FWIW, inter-channel crosstalk is typically very low on well designed consoles, we did look at it in the 8028 for example at the time we made the Neve summing plugin. It was even lower on the API desk we measured. The artifact is more obvious with tape machines. But for example with the ATR 102, the naturally occurring crosstalk is still way down there.
Hope this helps.

 

[shatzer]

Don't think I'd want crosstalk in my DAW. Drove me nuts hearing it on a cheap or old console.
However, I believe Studio One has that feature and you're able to control the volume of crosstalk per channel if I remember correctly.

 

[MakerDP]

Don't think I'd want crosstalk in my DAW. Drove me nuts hearing it on a cheap or old console.
However, I believe Studio One has that feature and you're able to control the volume of crosstalk per channel if I remember correctly.

Yeah the Studio One MixFX Engine can really destroy your stereo field if you are not careful! They waaayyyy overdid it IMHO. The LUNA summing is sooo much better.

 

[thomaskyhn]

Waves nls

When the NLS "Analog Summing Plugin" came out, there were complaints that it didn't do any actual summing.

 

[Joe Porto]

High end analog gear designers go to great lengths to keep noise and crosstalk to a minimum.

They are not features. They are unwanted artifacts. If they are included in a plugin, there should always be an option to bypass.

 

[Araya]

Studio One MixFX Engine is just a joke.
Add noise and crosstalk to get analog vibes... That's the intern joke.
But you can add tape emulation from softube which is pretty cool
I hope that UA will add its analog summing and/or tape simulation, but I don't really believe in it.