I am experimenting with parallel compression on my drum sound In Cubase 5 but strange things happen to the high end.

I set up a group channel DRUMS BPC (Before Parallel Compression) and route all drum tracks to this track. I set up an FX channel PC (Parallel Compression) with a compressor 1:8. With a send effect pre-fader from DRUMS BPC I feed this FX channel. I route both DRUMS BPC and the FX channel to a group channel named DRUMS APC.

Whatever compressor I use, whenever I push up the PC fader I get a phasy effect on the cymbals and I loose high end.

The strange thing is that this also happens with no compressor in the FX channel! Isn't the sound only supposed to get louder when I push up the FX channel? Is this a Cubase phase issue due to a small time difference between the arrival of the two signals at DRUM APC? Is'nt Cubase supposed to compensate for this. Or am I doing something wrong?

Any suggestions on what comnpressor to use for this purpose? Preferably freeware compressors as I only have Cubase and the Powercore platform.

Many thanks,

Daan

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...at the end of the day, it is what you do not what you say...(Spock's Beard)www.spocksbeard.com

You have provided a text book description of what happens when the correct delay compensation is not applied.

I'm surprised it is happening... but I'm not a Cubase user so can't offer any specific advice.

You could try inserting the same compressor plug-in (but set to 1:1 with the threshold turned up as high as it goes) to provide the same processing delay (but without adding any compression) in the clean drum group. That might resolve the problem....

However, the fact that it happens without a plug-in inserted in the FX channel implies something odd is happening to delay the pre-fade send in some way.

Are you sure nothing else has been routed inadvertantly to either of your drum groups, or FX channel -- or something is going to one of them AND to the main output? Easily done and could cause the effect you're describing.

Weird!

hugh

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Technical Editor, Sound On Sound

Cubase has had full signal path delay compensation for a loooooong time. Indeed, I've used parallel compression in cubase for as long as I remember and never had a problem related to delay.

If you duplicate a track, send one track to a group (no effects) and one not, do you get any phasing artifacts between them?

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An Eagle for an Emperor, A Kestrel for a Knave.

This only works for plugins that report their system delay properly. Many do not, especially in VST land. Try a different compressor or grab a demo from someone like McDSP ( theirs work correctly).

I did wonder if it might be a latency reporting issue, but the OP says he still gets the phasing even without a plug-in installed in the processing channel... which is very odd.

hugh

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Technical Editor, Sound On Sound

I've found very few compressors that fail to report the correct latency (Digitalfishphones being one).

Cubase does feature full automatic plug-in delay compensation. It's also possible to turn it of in the preferences, so that should be checked.

However, the OP says it's happening when there's no plug-in there - just a delay between the FX channel and the source channel. That's strange - and isn't happening here (and hasn't been in all the versions I can remember - and I've been using Cubase since way back and am now on 6.5).

So...
Try the same thing with a group track - FX channels offer you nothing that Group channels don't.
Check that ADC is enabled in preferences.
Check with a plug-in known to declare latency properly - eg Cubase's own compressors.
Post this question also at Steinberg.net's forum.

Can't remember off the top of my head which freeware features a wet/dry blend, but you could do worse than buy DDMF Metaplug-in which allows you to do all sorts of clever routing with any VST2.x plug-ins. For a good paid plug-in try Softube FET compressor for 1176 style compression with wet/dry, and try Cytomic The Glue for SSL/VCA compression with wet/dry.

Suspect it's just that ADC is off for some reason. If it is on, are the channels routed anywhere else? Do they both go to the same master output?

J

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www.jackruston.com

There are multiple places in Cubase where the delay compensation can be affected, including in preferences (at least two places there, IIRC), as mixedup said.

Another place is at the top left of the Project page, the "Constrain Delay Compensation" button. Try the project with that turned off (in other words, let Cubase do it's compensation).

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Alexis -Cubase 6.5.0/SX3.1.1.944, XP SP2, 4GB RAM (1GB not accessible, but used just to balance the computer so it doesn't tip over); Delta 66 in Omni i/O Studio; Motif8; UAD-1

Problems solved!

It turns out that if you bypass a powercore plugin using the Cubase bypass button (as I did) Cubase still applies latency compensation while the audio is not routed through the plugin. This creates phase problems.

I was not completely correct when I stated the problem occured "without any plugins". In fact I bypassed all plugins, which apparently is not the same. I had inserted the powercore plugin, then bypassed it and then tested other plugins to check which one I liked most in the role op parallel compression plugin. All showed the same phase problem which was caused by the bypassed powercore plugin.

I now removed the powercore plugin, inserted the Tessla compressor cranked up and got great results.

Thanks for helping me out!

My lesson for today: never bypass a powercore plugin in a parallel situation...

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...at the end of the day, it is what you do not what you say...(Spock's Beard)www.spocksbeard.com

Aah ok that makes sense. Remote dsp and delay compensation are often uneasy bedfellows.

Glad it's working.

J

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www.jackruston.com

Yep, I've discovered that with Poco and Liquid Mix stuff in the past. Should have remembered that. Well spotted. Has happened with one or two freebie/shareware native plug-ins too. Not a Cubase issue, but well worth being aware of. IIRC if you actually switch the plug-in off in the Cubase insert slot (power button) instead of simply bypass, the problem disappears. At least it did for me.

Quote Mixedup:

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Yep, I've discovered that with Poco and Liquid Mix stuff in the past. Should have remembered that. Well spotted. Has happened with one or two freebie/shareware native plug-ins too. Not a Cubase issue, but well worth being aware of. IIRC if you actually switch the plug-in off in the Cubase insert slot (power button) instead of simply bypass, the problem disappears. At least it did for me.

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Thanks for that!

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Alexis -Cubase 6.5.0/SX3.1.1.944, XP SP2, 4GB RAM (1GB not accessible, but used just to balance the computer so it doesn't tip over); Delta 66 in Omni i/O Studio; Motif8; UAD-1