Live 6 sports a wealth of new features, but for my money Instrument and Effect Racks are the most exciting. As I mentioned in my Live 6 review (SOS November 2006), the easiest way to convey the concept is to compare it to Reason's Combinator. Although there are significant differences, both Combinators and Racks allow you to build and save patches that consist of several devices (MIDI and Audio Effects, and Instruments). The devices are all held inside a container (the Rack) which acts as a single instrument, or device, that is placed on a mixer track in the same way as any other Live device or plug-in. Racks receive MIDI data, which can be passed on to the internal components in various ways (allowing you to create keyboard splits, velocity splits and layers), and have eight user-assignable knobs. Each Rack also has audio inputs and outputs for creating custom effects devices, and the signal flow can be set up between the internal devices when creating the patch. There's more on the basic concept of Racks in the review, along with some examples. In this month's Live Technique I want to get into the details of how to build your own Rack devices, with a couple of step-by-step exercises.
When you load preset patches on a workstation keyboard or a hardware drum machine, what you get is usually somewhat more than a single naked sound source. At the very least, the sound is probably being processed by some of the synth's onboard effects. There's also a good chance that the patch is made up of two or more sounds layered together. Going further, the sound may be arpeggiated, and the unit's knobs will have been assigned to control relevant parameters to make the patch dynamic and playable. In previous versions of Live, it was possible to achieve similar results by combining instrument plug-ins, MIDI effects (like the Arpeggiator), and audio effects in a track. This kind of configuration could be saved in Live 5 as a Device Group (.adg file). However, creating a layered sound would mean using two or more tracks, and anything further than that would be ugly or impossible. Racks make a lot more possible.
In the following example, we'll go from creating a basic instrument patch with effects, to a layered patch with custom controls. This example uses patches from the free Simpler Electronic Live Pack, but the same can be applied to any instrument plug-ins.
Begin by creating a MIDI track, and load the Simpler patch 'MS Seq' (from the Bleep folder in the Simpler preset directory) by dragging it into the device area. You can play the patch by clicking the 'In' button on the track's monitor section.
To the right of the Simpler, you will see the blank area labelled 'Drop Audio Effects Here'. Drag a Chorus into this area from the browser. Now select both the Simpler and Chorus by Shift-clicking their name bars, and choose 'Group' from the Edit menu. The devices are put into a Rack, which is bound on the left-hand side by a thin column with several icons, and on the right by a grey panel with an output meter display, as shown in the picture below. Save the Rack by dragging it to the browser. I've put it in the Simpler Bleep folder and renamed it.
So far, we've done nothing that wasn't previously possible when making Device Groups. The next steps will take us into new territory. Click the small icon with three horizontal lines in the column to the left of the devices. This opens up the Rack's Chain List panel. A Chain in Live is the name for a string of devices, such as the Simpler and Chorus we just made. In Live 5, a Group patch was always a single Chain, but Racks can contain multiple parallel Chains. A layered synth patch has multiple instrument Chains, but you can also use Chains to create an effect device that processes a signal through multiple effects in parallel. The parallel nature of Racks can also be used for switching in real time between device groups, as we'll see later. The Chain panel shows a list of the Chains in our rack; at this point there is only 'Chain 1', which is our Simpler and Chorus. This can be renamed by right-clicking.
Underneath the list is a blank area labelled 'Drop MIDI Effects, Audio Effects, or Instruments Here'. Drag the Simpler Patch called 'OB F-Bass' (in Simpler's Bass folder) into the Chain List. This automatically creates a new Chain with just this Simpler in it. By clicking in the Chain List, you can select which Chain is displayed in the main device area to the right. Set the relative levels of the two Chains by adjusting the dB fields in the list.
Clicking the top icon in the Rack's main panel (which looks like the Ableton logo) displays the assignable knobs, or Macros (see the screen at the bottom of the page). These Macros can be mapped to parameters on any device in any Chain, and can control multiple parameters at once. Let's assign the first knob to control the filter envelope amount on both Simplers. First click the 'Map Mode' button above the Macros. All assignable parameters will turn green. Now, select the first Chain by clicking it in the Chain List. Right-click on the Simpler's Filter Envelope Amount field and choose 'Map to Macro One' (as in the screen below). Repeat the process for the Simpler in Chain two.
At this point you can continue mapping your controls, but you may wish to add MIDI effects or further audio effects. Often you want these effects to act on all Chains at once, a situation which is discussed further in the 'Nested Racks' box on the next page.
In this simple example, all the devices are triggered by MIDI notes from the track, and the Macros simply group significant parameters into one place. However, with some further editing you can create more sophisticated instrument patches. Clicking the 'Key' button in the Chain List section opens up a new panel with a mini keyboard display along the top (see the screen above). Each Chain in the list has a brown bar representing the range of keys to which it responds. Trimming the bar from either end allows you to limit this range and set up keyboard splits. By leaving overlaps and adjusting the narrow bars above each main bar you can create crossfades between zones. This is particularly useful when used in conjunction with the velocity map (accessed from the 'Vel' button), giving you the option to make sounds that change smoothly from one Chain to another, depending on how hard you strike the keys.
Macros can be edited to limit the range over which they adjust their assigned parameters. This can be used both to limit the parameter within a useful range for a particular sound and to set up a good balance with other parameters that share the same control. For example, the screen at the top of the next page shows the Macro mappings I made for the example Instrument Rack above. This display appears in the browser area whenever you are in Map Mode. The second knob is assigned to the filter frequency on both of the sound layers in the patch. However, I've adjusted the frequency ranges to achieve the most consistent sound as you turn the Macro knob. Sometimes you might want to create a Macro that works in the opposite direction (reversed polarity) to the control it is mapped to. To do this, set the Min value higher than the Max value, or simply right-click the Macro in the list and choose 'Invert Range'.
What happens if you want to add an Arpeggiator, and some global effects to a layered Instrument Patch? Arpeggiation is achieved in Live by placing an Arpeggiator MIDI effect device before an instrument in the track. To do this with an Instrument Rack, you must either place the MIDI effect before the Rack or put copies of the same effect at the start of each Chain. It's a nuisance that you can't put one MIDI effect within the Rack to control multiple Chains. The same thing applies at the other end of the Rack for any audio effect that you want to apply to all Chains: either place it outside the rack so it receives the mixed output, or add a copy of the effect to every Chain. This allows you to save the whole configuration as a Patch, but is wasteful of processor resources. An alternative is to put the effects outside the Rack, then Group the whole configuration as a new Rack, creating a Rack within a Rack. The main picture on the previous pages shows how this looks if you add an Arpeggiator and Filter Delay to our Instrument Rack.
The down side of this technique is that it creates an extra layer of Macro Controls. You can use both sets of assignable knobs, but each set can only control devices within its own rack. However, you can assign the controls on the top-level rack to the Macros in the embedded rack. This means that you then have to assign the controls twice: once to assign a parameter on the original Instrument Rack, then again to assign that Macro to a Macro on the 'master' Rack. Needless to say, the ability to add global MIDI and audio effects to multiple Chains in a single Rack is top of my wish list for features in Live 7.
As well as creating complex instrument patches, Racks can be used to create effects Chains for use on both audio and MIDI tracks. In addition to the useful combinations of effects that were possible with Live's earlier Device Groups, Racked effects can work in parallel, and are considerably easier to use, thanks to Macro assignments. Effect Racks are created in the same manner as in the example we looked at earlier, and there are many examples in the factory library for inspiration. However, let's explore an example that demonstrates the considerable power of another feature of Racks: the Chain Map.
November's review gave an example of an Effects Rack that could switch between several effects. The idea is that during a live show or DJ set you could use this Rack in each track, and quickly select and manipulate effects on any channel, in a similar way to Native Instruments' Traktor, for example. Let's look at how to build this Rack...
1. Add a Beat Repeat effect to an audio or MIDI track, and 'Group' it (as we did in the previous example) to create a Rack.
2. Drag other effects directly to the Chain List. I've used an Auto Filter, Phaser, and Delay. This creates several Chains, each containing just a single device. By default, all the Chains are active, so any signal passing through the rack will be processed by all the effects (in parallel). The aim however, is to be able to select one active device at a time.
3. Click the 'Chain' button above the Chain List. This brings up the Chain Map, which shows brown bars for each Chain laid out against a 0-127 grid. Notice that there is an orange marker on the grid. The brown bars can be adjusted to only cover different ranges on the scale, much like in the Velocity or Key maps. The orange marker can be moved up and down the scale. Only Chains whose range the marker falls within are active.
4. Right-click in the Chain List and choose 'Distribute Ranges Evenly'. The Chains will then each be assigned their own unique range.
5. Create a Bypass Chain. To do this you can add any effect to create a new Chain, then delete the device so that the Chain does nothing. Create a range for the Bypass Chain that covers just one unit on the grid at the lower end of the scale. Trim the neighbouring Chain so that they don't overlap.
6. Assign a Macro to the Chain Select marker. You can then use this Macro, and any hardware controller mapped to it, to select which effect is active. When the knob is fully anti-clockwise, the effects are bypassed.
7. Add further Macro assignments to control the effects. One option is to use just one or two Macros and assign them to parameters on every effect, meaning that in a live situation you'd only need a couple of knobs to control all your effects. The finished Rack is shown in the screen above.
Once you've saved the Rack, you can drag it into as many tracks as you need. The new MIDI remote features in Live 6 mean that as long as you have a supported controller you can control all your Racks from one place. To control any Rack in the session, click it and a hand icon appears on it, indicating that your MIDI controller is now focused on this device. Any available knobs or sliders will be assigned to the Macro controls automatically.
Once you've mastered the basics of Racks, there's an endless number of applications you can turn them to. You can take the principle of the multi-effects patch above and apply it to instruments, making it easy to switch between sound sources when playing live, or apply Racks to sound design, layering sounds and effects, and morphing between them. Live's instruments have always lent themselves to tweaking and programming, rather than preset browsing, and Racks make it possible for any user to create complex and unique patches.