Tuesday, August 5, 2008

Audio Recording in Ubuntu Studio - Part 3: Adding Effects to the Ardour Drumtrack

Okay, by now you should have a drum track recorded in Ardour as the first step for your recording project. If not, check out Audio Recording in Ubuntu Studio - Part 2: Recording a Hydrogen Drumbeat. The drum track really is the backbone to your recording because it is often filled with the most emotion (i.e. build-ups, double tempos, break-downs etc.) However, in order to allow the recording artists to feel the full emotion of the song, we must add a few basic effects. These effects can then be tweaked towards the end of the project for the final mixdown.

Let's take a look at what we have. The figure below shows my multiple drum track recording of Sunday Bloody Sunday in Ardour.

It is important to record the drums as dry (i.e. no effects) as possible because this will make your recording more versatile. You can easily add effects to a dry recording but you cannot easily remove recorded effects. The above tracks are therefore dry and can be heard from the MP3 below.

DryDrums.mp3 (555 kB)

We now need to add effects to each drum by using Ardour's Mixer. The mixer can be opened from Ardour's Window menu by selecting Show Mixer (or pressing Alt+M). This should look similar to the one below, minus all the effects on each drum.

You can add effects to each drum by right-clicking in the black rectangle above each drum's level fader and selecting New Plugin. A list of all your installed effects will be shown, choose the relevant effect and select Connect. You should now see your effect appear in the black rectangle. The effect should still be bypassed so double click on it and a window displaying all the effect's options will appear. You can vary the effect options and click the Bypass button to switch the effect on or off.

Now that you know how to add effects, which effects best suit drums? Firstly, if you want a natural sounding drum kit, stay away from EQ. The effect which is easiest and most effective for use on drums is reverb. I used the TAP Reverberator which requires a a stereo input. I therefore used the Hilbert Tranformer to convert my mono track to a stereo one. I also used the TAP Equalizer to make my kit sound a bit more like U2's, but as I said earlier, be subtle when using the EQ. The drum track with added effects can be heard from the MP3 below.

WetDrums.mp3 (555 kB)

Compressors are very useful for drums because they make the drums sound powerful. However, you can add these during the mixing stage of the project. The early use of effects is merely to inspire the artists with a emotion-provoking drum track. For more information on some cool Linux effects, check out this post: My Favourite Linux Audio Effects.

In the next part of the Audio Recording in Ubuntu Studio series, our song should start taking shape as we add a guitar track.

Other posts you might find interesting:
Audio Recording in Ubuntu Studio - Part 1: Plan your Project
Audio Recording in Ubuntu Studio - Part 2: Record a Hydrogen Drumbeat
Overview of Compression
Hydrogen Drumbeat Templates - A Non-drummers Best Friend
Panning for Gold


Nick said...

Nice post !

This should help people like me getting started in ardour since i'm not too familiar in linux environnement (especially in the audio).

I have a little question concerning effects. What are the differences between "pre" and "post" effects, since in ardour we can add both ?

And also, everyone (or every tuto) puts their effects in "pre" (that's what i do and it's sound good) but wich kind of effects do we place in "post".


Brian the Lion said...

Hey Nick,

Thanks for the feedback. Pre effects are inserted onto the track before the level fader in the mixer, and post effects are inserted after the level fader.

In other words, if you are using a compressor and place it as a post effect, you will struggle because everytime your adjust your level fader, your compression sound will change. However, if you place the compressor as a pre-effect, the compression will sound the same even when the level is changed.

I hope that makes sense. You can see in the screenshot of the mixer in this post that the master track has a post-effect/insert - this goes to JAMin for mastering. I can therefore use the master level fader to ensure that no peaks are hit before it goes to JAMin.


Mike the Tike said...

Tha ardour tracks in the mixer go from top to bottom. So you can think of the raw sound in the track coming in at the top, flowing down through each of the sections in the mixer and finally going to an output at the bottom. As Brian said, you can insert effects (also sends and inserts) before or after the fader.

BTW, the order of the effects in each block also flow from top to bottom.

Nick said...

Thank you guys for your awnsers ! It make lot of sens to me hehe

Anonymous said...

This is the nuts. Just what I need. I'm looking forward to future posts.

brazh said...

Hi, Brian! Your blog is very very useful! I've used Windows for audio recordings before, but now I want to use Linux for this purpose. So, your blog gives the best fit for some questions!

I have one question, maybe you can help me: how to make a drumtrack in Hydrogen, using several drumkits? Or how to combine several drumkits into the one?

Excuse me, that I'm asking you here. Thank you!

Jakob Lund said...

Normally, reverb is considered a 'bus' type effect. Channel inserts are supposed (IMO) to be for EQ's and compressors and stuff like that.

In Ardour you can create a bus the same way you create a channel (just select 'bus' instead of 'channel').

To add reverb to drums, I'd prefer creating a reverb bus (mono, in this case -- remember to name it 'Reverb' or similarly right after creating it, that makes it easier), and insert the plugins (hilbert splitter + stereo reverb) on that (pre fader). On each drum channel then, create a 'new send' POST FADER, instead of 'new plugin', and then connect the send to the reverb bus (this is when it's nice to have named the bus, because Ardour will give you all its available inputs to choose from when you connect the send.)

The benefit of this approach is that the reverb is only run once (saves CPU), and you can change the settings, plugin etc, for all the drums in one place (saves you time). It also ensures that the 'room' setting in the plugin is the same for every drum, which all in all may sound more realistically (than, for instance, putting the snare in a cellar and the hi-hat in a cathedral :-) )

Brian the Lion said...

The comments on this post seem to be playing up a bit. All the comments get emailed to me but take an extra few days to actually appear.

I will reply to each comment when it appears on the blog. Sorry for the inconvenience.


Brian the Lion said...

Brazh said:

"I have one question, maybe you can help me: how to make a drumtrack in Hydrogen, using several drumkits? Or how to combine several drumkits into the one?"

In order to make one song using more than one Hydrogen drumkit, can be only be done by making a new Hydrogen drumkit which combines all the kits you want to use. This is not too difficult in Linux, but the Windows version of Hydrogen still has problems.

I have written a comprehensive post on How to make a Hydrogen drumkit. All you have to do is make a new kit with the sound files from the other kits. These sound files are definitely on your computer. Off-hand, I think they are saved in your usr folder under Hydrogen or somewhere around there.

I hope that helps,

Brian the Lion said...

Jakob Lund said:

"Normally, reverb is considered a 'bus' type effect. Channel inserts are supposed (IMO) to be for EQ's and compressors and stuff like that..."

Thanks for the awesome feedback, Jakob. That's actually a fantastic idea, and a far better way of doing it. I will try it out and do a post on it sometime in the future, if you don't mind?