Accurate Automation of High Pass Filter

Dear Forumers,

After a couple of hours of googling I’ve realized:

  • Cubase automation is rarely highly accurate.
  • Most VST-plugins don’t support sample accurate automation.
  • Automation accuracy may depend on buffer size and ASIO Guard.
  • Automation accuracy may be different when listening and when exporting.
  • However, Cubase channel volume automation is accurate.
  • These problems are not unique to Cubase but are present in many other DAWs as well.
  • On the forums these problems make people lose sleep about.

What I mean by “highly accurate” is accurate to less than a millisecond.
I have not yet researched this to be certain which of the points mentioned above are more significant than others.
If I understood correctly VST3-plugins support sample accurate automation if the plugin has been deliberately programmed to do so.
I tried disabling ASIO Guard to no avail.

The Question
Have you found a solution to this?
I need to make quick and accurate automation to High Pass filter.
Do you know a plugin that supports this kind of accurate automation in Cubase?
I’m willing to consider buying a plugin.

One bad “solution”:
Make a curve in Cableguys’ Shaperbox; enable the effect before the curve and disable after the curve:

Now, if I move the events in the song forward or backward in the project the curve could be off by multiple bars and unnecessary work will ensue.

…or… should I save up for Nuendo.

Thank You!

If you’re interested in what kind of a song would need quickly changing and accurate automation here’s a sample:

Automation is not sample accurate, that is usually not a problem.
What might be, is working\automating using high buffer setings, try using a as small as posible buffer. If you are using a controller that is, writing automation by mouse should be precise enough

I don’t use any hardware controller. I click and drag points.

There is a clearly audible lag between an automation point and for example Cubase StudioEQ-plugin actually changing parametres.

I had quite a low output latency when I tried different settings. The problem is that the snap of a kick drum lasts less than 5 milliseconds. If the snap is lost the automation is useless.

Just out of interest, what are you trying to achieve with 5ms automation points on kick drum, it´s quite quick modulation on low frequencies

Terve, Jari,

In this file:
at time: 1min 24sec 91ms
starts a bar during which there is a Low Pass filter automated.
The LP filter cutoff frequency changes quickly in a saw-like way.
This is achieved with Cableguys’ ShaperBox and it affects the entire mix.
The ShaperBox insert effect is bypassed when the next bar begins.

A less elaborate automation with Low Pass filter can be used just to make sections of a song tonally different (from dark to bright).
But in that case, too, it’s important that effect ends the millisecond the next bar begins.
Luckily it seems that insert effect bypass automation happens instantly.

Another way to make sections of a song tonally different is to use the High Pass filter to make a section sound thinner.

Of course, there are myriad ways to change the tone of a song but these just add some ‘polishing’.

Kick drum’s low frequencies:
My apologies for talking about only High Pass filter in the header and posts above.
I use both HP and LP filters in a similar context.
But of course (with LP filter) you can use wackier automation if you don’t go too low with the cutoff frequency.

Easily enough to mess up a drum transient -whether it’s automation of volume, of EQ or anything else significant.

As pointed out, the lower the buffer, the more accurate it is but for anything really critical or obvious in the mix, you may have to use a workaround e.g. Bounce to audio and edit the file, or copy the relevant section of audio to a new track etc.

And yes, this is not just a Cubase issue.

From my testing a while ago, this is not the case (unless anything has changed in more recent Cubase versions).

I tested the cableguys stuff and for some reason I found the timing to be pretty bad. I have good luck with fabfilter simplon. I don’t know if it’s sample accurate, but I don’t have any issues with timing with it. I’ll say that I have found enabling and disabling plugins to be a bad way to go as it can introduce clicks-unless I can do it in a section where there is no sound. Good luck!

By the way, do you guys know does Nuendo have better automation?

Ok, sounds like our results may vary. I’ll re-check the accuracy of volume automation. If it’s not quite accurate I’ll have to use it only in less critical stuff.

It could be that Fabfilter Simplon utilizes the VST3 specific high accuracy automation. If that works that’s great news!

For me, Cableguys’ ShaperBox has always been on time. Though I’ve been using it only for a couple of months now with Cubase. I thought ShaperBox would be unusable especially in high-tempo EDM if it had sloppy timing.

For now I’ll just pray I don’t hear any clicks when enabling or disabling an effect. But if they start appearing I have to figure out something different.

Fabfilter Simplon has similar lag.

Not for me. Maybe it’s not a plugin issue. Are you automating from an automation lane or from CC? If you are doing CC that is only midi resolution. Do you have the same problem regardless of the number of tracks you have? IE can you reproduce the issue with just one track?

Below is a mashup screenshot — I tried to include as much information into it as I could.
I tried with both with and without ASIO-Guard and with long and a bit shorter latencies: same result.
I always draw automation with ‘snap to grid’ on and let the points snap where they should.
The high frequencies of the second kick in the file get filtered by Simplon in a clearly audible way.
It sounds the same when working and in the exported file.

This is the resulting audio file (using mp3 just for Internet’s sake):

Should I set the “MIDI ON” to “MIDI OFF” in the Simplon?
I could of course make the automation 1/16 beat early if the lag is constant…

By the way, it seems that even insert effect bypass automation is not instantaneous.
But I was able to get better results by sending the audio to two Group Channels — the other one for the effect and the other clean — and automating the Groups Channels’ mute parametre.
It’s a bit of a hassle but not too much.

Maybe there simply is always some easing present when a plugin changes a parametre. Therefore — while the automation may be accurate — the easing can cause audible effect on a signal.
I will simply make the automation happen just a tiny bit earlier and call it a day.

But of course, if you have ideas, opinions or advice, it’s all appreciated!

Don’t forget, that there is a transistion time setting (soft/quick) for the internal filters in Cubase. It is located in the Mix Console window in the Functions Menu (the arrow on the right hand side in the top bar).


1 Like

S1 and PT don’t have the issue… Logic also has zero issues UNLESS You use latent plugins… then it’s out by the latency time… but seriously, if i could live with zero latency plugins only, logic would never be out of time…

This IS very much a Cubase thing, especially since it’s affected by buffer. Things seem better in V9 for me FWIW…

Cubase does it with any plugin, randomly… it alters the automation timing… zero latency plugins or plugins with latency, makes no difference.

Are you sure about S1? I worked with a Studio 1 user last year and we ran into problems with automation timing accuracy.

This thread describes the exact same issues with S1 (although it’s from a year ago so maybe has been resolved):

A good plugin to achieve this effect is LFO-Tool from XFer. I use this all the time for fast accurate volume, filter cutoff or even panning stuff. You can draw your own curfes, a 1/16 saw cutoff is very easy to create. And the dry wet slider respond very very fast while automated. Check it out :slight_smile:

Any one care to expand on if LFO tool is more accurate than Shaper Box. I’m a huge Shaper Box fan. Not just surmising.

I did not know this. Thank you.