Audio recording with GNU/Linux

Our album "X marks the spot" is going to be some sort of proof-of-concept that Free Software and GNU/Linux are ready for prime time when it comes to creating musical art. The new Drupal-based XBloome website already shows that it doesn't always have to be Photoshop and Mac to create good looking designs.

We're working with a very tight budget, and just like our first album, this one will also be a low-to-no-budget production - and we'll do our best to make it sound awesome as it should.

Software used:

Currently, the following components contribute the most to our recording environment:

• Ubuntu Hardy 8.04 GNU/Linux distro as operating system
• Ardour 2.8 a full blown Digital Audio Workstation for recording, mixing, mastering
• JACK Audio Connection Kit for low latency audio routing and inter-application audio connections
• Hydrogen drum machine
• FFADO / FreeBoB for our FireWire multi channel soundcard
• JAMin for stereo mastering
• LADSPA- as well as LV2-Plugins
• FMIT (Free Music Instrument Tuner) - a great tool for tuning and visualizing incoming sound
• Audacity
• ...and many more!

Our experiences so far are quite positive, and our very first try to record, mix and master a song with these tools can be heard in the Edelbrand version of our song "Slow Motion", which has been recorded in my living room and features the Hydrogen drum machine instead of the usual Rebirth 909/808 drums we usually have.

The heart of our setup is definitely Paul Davis' Ardour, a great DAW (which we are also supporting financially by a monthly subscription).

Plugins:

Right now I'm experimenting with different LADSPA/LV2 plugins, to find out which replacements for every day requirements like compression, equalizing, limiter, doubling, etc.
So far my personal favorites are (ordered by their usage amount):

• Compression:: Steve Harris' SC4 Compressor
• Limiter: Steve Harris' Fast Lookahead Limiter (This is my all-time favorite!)
• Equalizer: Steve Harris' Multiband EQ
• Reverb: GVerb and Freeverb
• Equalizer: Tom Szilagyi's TAP Equalizer (parametric)
• Limiter: Tom Szilagyi's TAP Scaling Limiter
• Steve Harris' Triple band parametric with shelves (For incredibly enhancing the "kick" and "beat" of the drums)
• Steve Harris' Delayorama (Adds more sex to the trumpet!)

Tipps & tricks:

Artificial "stereo-width"

I like to control the "width" of my signals manually. There's cheap way of doing this: Delay either left or right channel by a few milliseconds. The more you delay it, the widener the stereo image.

Quick HowTo:

1) Add a mono bus track

In Ardour, choose the menu option: "Track > Add Track/Bus" and add a new mono bus.
Change its name to "Left Delay".

2) Add "delay" plugin to the delay bus

Add it pre-fader.
I've used the LADSPA plugin "Simple Delay Line (by Richard Furse)", with the following parameters:

• Delay (Seconds): 0.078
• Dry/Wet Balance: 1.000

The "Dry/Wet Balance" value should always be 1, because smaller values would mix the original (non-delayed) signal with the delayed one, and this could lead to unwanted phase-interference but only on the one channel (because of the way we use it here) - and I can't imagine that this is good.

3) Route the signals

You cannot use "sends" for this, so you have to route it differently:
First: Connect the "Left Delay" bus' output to "Left Master". This only has to be done once.

Now, for each track you want to have control over its stereo-width, do the following:

• Disconnect the left output channel.
• Connect the left output channel to the input of the "Left Delay" bus.

Voila! Now you can give any signal more width in the stereo-mix, by increasing the delay.

Delay on the trumpet

I've never used delay as effect. I never liked it. But I've also never recorded a trumpet before. :)
During the mixing-session with Laura, she suggested adding a delay to the trumpet at the end of one song. Due to my lack of experience with delay plugins, we've tried our luck with Steve Harris' Delayorama (It caught our eye, because of its cool name).

1) Create a new stereo bus

In Ardour, choose the menu option: "Track > Add Track/Bus" and add a new stereo bus.
Change its name to "DelayORama".
Connect its output to master left/right (or optionally route it through a delay (see below)).

2) Add the delay plugin to the bus

Add it post-fader.

3) Add "Send" outputs

For each instrument/track you want to add the delayorama effect, add a new "Send" output post-fader:

1. Right-click in the mixer strip.
2. Select "New Send ..."
3. Make sure you have 2 outputs (out 1, out 2).
4. Under "Available Connections", select "DelayORama/in 1" and "DelayORama/in 2" (=left/right of DelayORama bus).

(Warning: Be careful if you rename the "Send" output, because each "Send" must have a unique name in Ardour!)

4) Improve stereo image of delays (optional)

In the HowTo above, I've explained how to increase the width of a signal in a stereo mix, by adding a delay on one channel. If you use this effect on the "DelayORama" channel, it has a really cool effect, moving the delayed parts to more distinguishable "position" in the stereo panorama.

Example parameters

Here's an example of Delayorama parameters I've used for our song "Brea":

• Random seed: 0
• Feedback (%): 7.812
• Number of taps: 6
• First delay (s): 0.379
• Delay range (s): 0.573
• Delay change: 1.000
• Delay random (%): 5.000
• Amplitude change: 1.000
• Amplitude random (%): 14.062
• Dry/wet mix: 0.333