We check out Logic’s new Synth Bass Session Player.
Last month we explored Logic Pro 12’s new Synth Keyboard Session Player. This time, we’re looking at its companion, the Synth Bass Session Player. Being part of Logic’s Session Player ecosystem, they share similar workflows, so here we’ll focus more on where they differ.
At its core, the Synth Bass Session Player is a virtual performer designed to automatically generate bass lines using synthesizer sounds. It integrates well with Electronic Drummer and, like the Synth Keyboard Player, defaults to using Alchemy, though of course you can swap this for any Logic or Audio Unit synth.
As with all Session Players, the best starting point is to populate the Chord Track to allow Synth Bass Session Player to generate musically appropriate bass lines that follow your chord sequences. It can also lock to the rhythm of a chosen track or adapt to arrangement markers, allowing patterns to develop dynamically across your song. From there, you can refine the performance by adjusting complexity, changing rhythmic styles, and selecting alternative patterns from the player’s library. One major advantage of Session Players is the speed with which they produce context‑aware patterns, but when you need more control you can easily dive into the piano roll to add all the nuance you desire.
You can refine the performance in various ways: by adjusting complexity, changing rhythmic styles, and selecting alternative patterns from the player’s library.
To get started, create a Session Player track and choose Session Player /Bass Player. Then, in the Details pane, select one of the three styles: Pump Bass, 808 Bass, or Sequenced Bass. Each offers distinct rhythmic behaviour and character, but they share a common control set.
In the Session Player editor, Complexity, Intensity and Articulation shape the feel of the bass line. Complexity determines how busy the pattern is, from simple root notes to more elaborate rhythmic figures, whilst Intensity controls velocity and note density, adjusting the overall energy. The Main tab’s X/Y pad shifts tonal behaviour: move beyond root notes and add more tonal choices by moving the puck left to right, whilst up/down changes octave range. Once you’re happy with the feel, you can dig deeper into parameters affecting range, filters, LFOs, articulation, glide and slide.
Pump Bass
Pump Bass produces a driving, pulsing bass line that locks in with the downbeat, whilst emphasising offbeats in a side‑chain‑like swell. Normally, this effect would require routing a kick drum track to a compressor’s side‑chain input. Here, it is handled through a dedicated Pumping parameter which, under the hood, uses real‑time region‑based automation that controls MIDI CC11 (Expression) to ramp the loudness of each note, as if reacting to a four‑on‑the‑floor kick. You can adjust the effect’s shape and amount, and even re‑target the modulation to other CCs such as filter cutoff. And, as noted last month, you can now view and edit notes and automation directly without converting to MIDI: open the piano roll (P), show automation (A), then switch the lane from Velocity to Expression.
By contrast, 808 Bass aims for the deep, sustained sub‑bass style associated with the Roland TR‑808 and commonly used in hip‑hop and adjacent genres, where kicks and bass blur into a single low‑frequency voice. As such, you can expect long notes, occasional slides and pitch changes, and an emphasis on weight rather than rhythmic detail: bass that’s more felt than heard. In place of Pumping, we have Repeats, Triplets, Slide and LFO controls, helping shape the expressive glides and subtle movement typical of 808 lines.
Everybody Needs A 303
Sequenced Bass takes inspiration from classic step‑based patterns, and is more akin to the Roland TB‑303. It’s the most melodic and rhythmically varied of the three styles, with syncopated patterns that can evolve over time. It’s a brighter sound, richer in harmonic content than the 808 and thus giving the bass more prominence in your track. After choosing a rhythm from the Patterns menu and tweaking the X/Y pad, you can explore a wide range of articulation by balancing note length with slide amount/time. A short note length of around 10 creates a punchy staccato; push to the right for a more fluid, legato movement.
...there’s fun to be had by engaging with the Transform Pad, for wild, morphing timbres.
In the LFO tab, the default modulation target is Alchemy’s Filter 1 cutoff. Lowering the cutoff and boosting the resonance immediately pushes the sound toward classic 303‑style squelch. Combining this with Filter 2 introduces even more possibilities, from clean sub‑heavy shapes to gritty, overdriven textures, depending on filter type. As well as the usual processors and effects Alchemy offers for compression, reverb, delays and so on, there’s fun to be had by engaging with the Transform Pad, for wild, morphing timbres.
Overall, the Synth Bass Session Player functions well as an artificially intelligent collaborator within Logic Pro, allowing you to quickly create and tailor synth bass lines to your project.