Wednesday, May 28, 2008

My Favourite Linux Audio Effects

Ubuntu Studio comes with hundreds of pre-loaded effects. Although I haven't gone through all of them, I have come across severval effects I found useful. I have described each effect below and also provided a screenshot in order to get a basic idea of what controls they have.

  • Equalizers

    Equalizers are used to individually vary the gain of several frequencies.

    Multiband EQ (by Steve Harris)

    This EQ has 15 frequencie faders (50 Hz - 20 kHz). Each fader's gain can be increased to 30 dB and decreased to -70 dB. See figure below.

  • TAP Equalizer-BW (by Tom Szilagyi)

    This EQ has 8 floating frequency faders along with gain and bandwidth faders. i.e. You must select the frequency that you want to boost/attenuate and then alter the gain. The bandwidth [usually referred to as quality (Q)] determines how much the surrounding frequencies are affected i.e. width of the notch.
  • Reverbs

    Reverbs essentially simulate a room/hall sound by introducing echoes.

    Gverb (by Juhana Saderharju)

    I found that this reverb was quite easy to use and produced fairly decent results with a bit of tweaking. The faders are pretty self-explanatory.

    Plate Reverb (by Steve Harris)

    This is a very simple reverb for quick and easy use. The damping fader determines how much of your higher frequencies are included.

    TAP Reverberator (by Tom Szilagyi)

    This is by far the most versatile of the three reverbs I've mentioned. The most important thing to remember is to set your reverb type. It defaults to Afterburn which sounds pretty bad. I like the Halls, Rooms and Plates.

  • Compressors

    Compressors allow you to either bring down louder parts or bring up the softer parts. This allows you to get more punch out of your mix. Check out my
    Overview of Compression post for more information.

    SC4 and SC4 mono

    The SC4 compressor is for stereo tracks and the SC4 mono is for... can you guess?...mono tracks. It has all that I require from a compressor as well as a neat Gain Reduction meter which shows you when it is working and how much is being compressed. The faders can be complicated if you haven't used a compressor before so please check out my post:
    Overview of Compression if you are confused.

  • Amplifier Simulators

    These effects aim to simulate how a certain type of amplifier would make an instrument sound.

    TAP TubeWarmth (by Tom Szilagyi)

    This cool effect, recommended by a fellow Brian's Bedroom reader here, basically makes you track sound fat (or phat if you're a gangster). It does this by simulating a tube amplifier which typically have a warmer sound. Drive is the essentially warmth and the Tape-tube Blend is basically a wet/dry mix fader.

Other posts you might find interesting:
Overview of Compression
High There?!
Live Sound, Monitors and Pepper Spray
Speaker Placement
Panning for Gold

Wednesday, May 21, 2008

How to Make a Hydrogen Drumkit

This post explains how to create a Hydrogen drumkit without editing any code i.e. a point-and-click method. This may sound complicated but it is actually really easy. So when you decide to do this, simply refer back to this post and follow the steps. Here we go:

  1. Open Hydrogen (No-brainer), and make sure the Instrument Editor window is open.
  2. Go to View and select Show Drumkit Manager. Select any drumkit and click Load Drumkit. This will be used as a base for your new kit.
  3. I will assume that you already have the relevant sound files, you want to create the kit with, saved into a file (.wav, .flac, .au or .aiff formats).
  4. Select the relevant instrument you want to edit, i.e. Snare, and view it in the Layers tab of the Instrument Editor window. You should see something similar to the below figure:
  5. Select the blue horizontal block and click on the Delete Layer button.
  6. Now you want to add your own sound, so click on the Load Layer button. This opens a file browser which allows you to choose your sound.
  7. Select your sound and click Open. Your sound is now loaded as an instrument.
  8. If you want to use multiple layers for each instrument, i.e. soft and loud snare hits, you must load another layer. This is done by repeating step 6.
  9. With multiple layers you need to edit the volume at which each layer is activated. This is done by shrinking the blue horizontal bars in the Instrument Editor. As seen in the below figure, the two layers look like steps. This means that at high volumes the 1st layer will be used and at low volumes the 2nd layer is used (i.e. left is quiet and right is loud).
  10. You can rename your instrument by clicking on its name in the Instrument tab of the Instrument Editor.
  11. The Instrument tab also has some cool knobs which can be used to edit your instrument's sound. The most important of these is the instrument gain which allows you to raise or lower your instrument's volume to match the other parts of the kit.
  12. The Layers tab also has cool knobs. The gain knob edits the selected layer's gain and the pitch knob makes the selected layer sound either higher or lower.
  13. To add more instruments, simply select another instrument and repeat steps 6 to 12.
  14. Once you are happy with your kit, you have to SAVE it. This is done by visiting the Drumkit Manager mentioned in step 2. Select the Save tab and replace all the details with your own. Make it official by clicking on the Save button. You have now made your own drumkit. I recommend that you save periodically whilst making your kit - you don't want to lose all your work.
  15. Once you feel your kit is complete and you haven't done anything illegal like stealing proprietary sounds. Export it by using the Export tab in the Drumkit Manager and then post a link to it both as a comment to this post and on the Hydrogen Forum. Check out for free file hosting/sharing.
Let me know if this information was useful by rating this post.

Other posts you might find interesting:
Making a Roll Sound Realistic
Pimp my Beats
Multiple Outputs for Hydrogen
My Attempt at a Hydrogen Drumkit
Hydrogen Drumkits

Monday, May 12, 2008

How to Capture Audio from Video

I have recently been trying to capture audio from some video clips that I have, and just didn't know how to do it. I thus stumbled upon an awesome way using Ubuntu Studio's default movie player, Totem Movie Player.

It is very simple, let me explain...

  • Open JACK and start it.
  • Open your video of choice using Totem.
  • Go to Totem's Edit menu and select Preferences.
  • Select the Audio tab in preferences.
  • Use the scroll down menu to change the Audio Output Type to AC3 Passthrough
  • Your movie audio is now passed through JACK and can be recorded with any recording package which uses JACK i.e. Ardour.
  • The Totem audio outputs can be viewed from JACK's Connect menu.
And if you're wandering why on Earth something like this would be useful...well, you can always choose your favorite line from a movie and convert it into an SMS/Text message tone.

Other posts you might find interesting:
Beginner's Guide to Ubuntu Audio Recording
Live Sound, Monitors and Pepper Spray
My Favourite Linux Audio Effects
Hydrogen Drum Machine Basics
Microphone Review: Shure's SM57