Delay compensation, SC48

[[email protected]]

Having watched Scoville's parallel compression tips webinar...I have a few simple questions on an SC48:

- If you have a plugin on a single channel, does delay comp have to be on in order for the rest of the channels to be auto-aligned at the main buss L/R??

- If you fed a single input into 2 single channels, and put inserts on one and left the other dry...would delay compensation align them if they were both coming into the L/R buss? Or are you required to manually delay the dry one?

- For FX bussed plugins...how is the latency accounted for when the signal is returned to the main buss??

Thanks!

[Scott Fahy]

1. Yes, also remember to take an unused channel and press all of the buttons (L/R, C, all groups) it was one of the things Robert said "tricks" the console to aligning things
2. If you feed them into separate groups the delay compensation will take care of it, if you feed them directly to L/R I believe you would need to align them at the channel level.

3. Not sure about the last question, but wondering why it would matter since by nature the plug in already changed the time anyway.

[Sheldon Radford]

Hi Terry,

I'll expand on this a bit.

- If you have a plugin on a single channel, does delay comp have to be on in order for the rest of the channels to be auto-aligned at the main buss L/R??

For parallel compression scenarios, yes. The delay compensation engine is used to align signals that are double-bussed. I.e., the same signal that arrives at a destination from two paths (for example, direct to LR, and also through a grow assigned to LR). Now, to clear up a common misconception...

Delay compensation does NOT automatically align all input channels going to mix just because a plug-in has been inserted on one channel. If channels aren't being double bussed, no additional latency is introduced, even if delay comp is on.

- If you fed a single input into 2 single channels, and put inserts on one and left the other dry...would delay compensation align them if they were both coming into the L/R buss? Or are you required to manually delay the dry one?

There's no double-bussing here, so this is a case that needs to be handled manually. The easiest way to do this is to right click on the Inserts section of the "wet" channel, note the value of the process delay (this is the total delay incurred by inserted plug-ins), and then add this value to the built-in delay of the "dry" channel. A user preference on the OPtions page allows you to display delay values in samples instead of ms.

- For FX bussed plugins...how is the latency accounted for when the signal is returned to the main buss??

No compensation is applied in this case. Effects being fed by a bus are typically time-based effects to begin with (reverbs, delays) so the few sample of latency added by the plug-in routing are inconsequential.

Sheldon

[[email protected]]

Ah! This is very helpful Sheldon...thank you!!

[Adam C]

Hi Sheldon,

Thanks for that info...

So - I have a couple of Sansamp plug-ins that I'm using to add some distortion to drums and vocals on certain songs. The one on drums is sent from a post-fader aux and returned to a channel, so does this mean it won't be delay compensated? If I inserted it on a group instead would it then be delay compensated? I'm running 16 auxes plus 8 variable groups so using a variable group would be easy enough on the send side of things, but I would rather have it returning to a channel where I can get to it more easily. I normally keep my output fader bank on VCA when I'm mixing. Is there a good workaround for that?

The Sansamp plug-in for the vocal is run on a split from the vocal channel. So I have the clean vocal channel, with a de-esser inserted, and then another channel from the same vocal mic preamp, with the Sansamp inserted (no de-esser). It sounds like they won't be delay compensated... how can I fix that? I realize I can manually delay one of the channels, but how can I find the needed delay?

Thanks!!

[Sheldon Radford]

Hi Adam,

So - I have a couple of Sansamp plug-ins that I'm using to add some distortion to drums and vocals on certain songs. The one on drums is sent from a post-fader aux and returned to a channel, so does this mean it won't be delay compensated?

No, it will not be compensated.

If I inserted it on a group instead would it then be delay compensated?

This will be compensated for if double-bussing occurs. For this to happen, the "Dry" channel would be routed to the group (w/ effect inserted) and also to LR; the group would also be routed to LR, which creates the double-bussing.

...but I would rather have it returning to a channel where I can get to it more easily. I normally keep my output fader bank on VCA when I'm mixing. Is there a good workaround for that?

Depending on your workflow and available number of buses or VCAs you might be able to use the VCA or Group "spill" feature to access the dry and wet channels.

The Sansamp plug-in for the vocal is run on a split from the vocal channel. So I have the clean vocal channel, with a de-esser inserted, and then another channel from the same vocal mic preamp, with the Sansamp inserted (no de-esser). It sounds like they won't be delay compensated... how can I fix that? I realize I can manually delay one of the channels, but how can I find the needed delay?

1. Select the wet channel
2. On the Inputs page, right-click in the area where it says Inserts
3. Note the "Process Delay" value, in samples
4. Repeat steps 1-3 for the dry channel
5. Apply the difference of these two values to which ever channel has the least process delay

Example (not actual values - you'll still need to check these):
Channel 1 with de-esser = 7 samples of process delay
Channel 2 with Sans Amp = 9 samples of process delay
Result: add 2 samples (9-7 = 2) to Channel 1 to align it with Channel 2.

Sheldon

[Adam C]

Great!

That clarifies things a lot.
I couldn't remember to right click the inserts area to find the delay.

Thanks Sheldon!!

[digidesigner]

I would point out that not all plugins report their latency correctly. It's good to do some testing if you want to be 100% sure everything is summing up nicely.

Edit: Also I think the connections between plugins (time slots?) take time, so if you have number of plugins in use in a row it might not be enough to just add the reported latency numbers together. How about it, Sheldon?

[Sheldon Radford]

Also I think the connections between plugins (time slots?) take time, so if you have number of plugins in use in a row it might not be enough to just add the reported latency numbers together. How about it, Sheldon?

Routing to/from the plug-in rack and between plug-ins inserted in series does involve a few samples. When you right-click in the "Inserts" section of the Inputs or Outputs page it shows the total process delay, which includes the aforementioned routing delay.

So right-clicking on the individual plug-in gives you that plug-in's process delay, while right-clicking on the Inserts section gives the full picture.

Sheldon

[digidesigner]

Thanks Sheldon!