Session 10

Session 10: Filters & EQ — Multi Mode, Parametric, DJ Kill

25 min|intermediate|patch

Session 10: Filters & EQ — Multi Mode, Parametric, DJ Kill

Objective: Master the OT's three frequency-shaping effects — the 12/24dB Multi Mode Filter for sweeps, the Parametric EQ for surgery, and the DJ Kill EQ for performance. Apply a filter to a drum loop and automate the cutoff via a p-lock.

If you only have 5 minutes

Track 1 with a drum loop. FX1 = 12/24DB MULTI MODE FILTER, MODE = LP, FREQ = 60. You hear muted thump. Turn FREQ to 100 — the loop opens. That's the workhorse effect, learned.

Warm-Up (2 min)

From Session 09, you have a Pickup machine looping. Press [PLAY]. While it plays, you might already be thinking "I want this part to be brighter, that part darker." That instinct is what filters and EQ exist for. Stop. Time to build the toolkit.

Setup

Start from the LAB project. Track 1 should have a drum loop or beat (any 1-2 bar loop). Place trigs across the pattern (e.g., trigs on 1, 5, 9, 13 for kicks; or use a sliced break with sample locks). Press [PLAY] to confirm sound.

Exercises

Exercise 1: 12/24dB Multi Mode Filter — The Workhorse (7 min)

The Multi Mode Filter is on every OT track. You'll use it more than any other effect.

  1. Press [TRACK 1], then [FUNC] + [FX1] to open FX1 SETUP
  2. Turn knob A to choose 12/24DB MULTI MODE FILTER. Press [NO] to exit
  3. On the FX1 page, the parameters are now:
    • MODE (knob A) — LP1, LP2, BP1, BP2, HP1, HP2, BR (band reject), PK (peak)
    • FREQ (knob B) — cutoff, 0-127
    • RES (knob C) — resonance, 0-127
    • TYPE (knob D) — 12DB (smooth) or 24DB (steeper)
    • ATK / DEC (knob E/F) — envelope on the filter
  4. Set MODE = LP2, FREQ = 60, RES = 40, TYPE = 12DB. Press [PLAY]
  5. Slowly turn FREQ from 0 to 127 — classic filter sweep
  6. Bring RES up to 90 — resonant peak emerges. Beautiful and dangerous
  7. Try MODE = HP2 for a high-pass sweep (removes low end as you raise FREQ)
  8. Try MODE = BP2 for a band-pass (only mid frequencies pass)
DATA ENTRYTRACK PARAMSVOLUMEHP VOLLEVELOCTATRACKPTN A01 PART 1BPM 120.0Octatrack MKIIABCDEFPLAYSTOPRECTEMPOFUNCPROJPARTAEDMIXARRMIDISRCAMPLFOFX1FX2SCENE ASCENE BCROSSFADERREC1REC2REC3PTNBANKPAGEUPDOWNLEFTRIGHTYESNOT1T2T3T4T5T6T7T8CUETRIG 1TRIG 2TRIG 3TRIG 4TRIG 5TRIG 6TRIG 7TRIG 8TRIG 9TRIG 10TRIG 11TRIG 12TRIG 13TRIG 14TRIG 15TRIG 16

Exercise 2: P-Lock the Filter Cutoff (5 min)

Static filters are fine. Animated filters are music.

  1. With FX1 = Multi Mode Filter set up, set FREQ = 100 (open) and stop the sequencer
  2. Hold [TRIG 5] — the screen shows "Step 5 LOCKED". While holding, turn knob B (FREQ) down to 40
  3. Release [TRIG 5]. Step 5 now has a p-lock: the cutoff drops on that step only
  4. Press [PLAY]. You'll hear a momentary filter close on beat 2 (where step 5 is in a 16-step pattern)
  5. Repeat: hold [TRIG 9] + turn FREQ to 30. Hold [TRIG 13] + turn FREQ to 60. Now the filter is animated across the pattern
  6. Look at the pattern — locked trigs show a different LED color (often amber/yellow vs. red)

Exercise 3: 2-Band Parametric EQ — Surgical Cuts (5 min)

Parametric EQ is for fixing problems and shaping tone, not for sweeps.

  1. Press [FUNC] + [FX2] to open FX2 SETUP. Choose 2 BAND PARAMETRIC EQ. Press [NO]
  2. FX2 parameters:
    • F1 / F2 — frequency for band 1 and band 2
    • G1 / G2 — gain for each band (cut or boost)
    • Q1 / Q2 — bandwidth (narrow or wide)
  3. Set F1 = 40 (low-mid), G1 = -12 (cut), Q1 = 60 (medium width)
  4. Set F2 = 90 (high), G2 = +6 (boost), Q2 = 40 (wider)
  5. Press [PLAY] — the loop has its low-mids cut (often muddy area) and highs boosted (presence)
  6. Surgical cut workflow: boost a band by +12, sweep the FREQ to find an offending resonance, then flip the gain to -12 to cut just that frequency. Standard mixing technique

Exercise 4: DJ Style Kill EQ — Performance Mode (4 min)

DJ Kill is built for hands-on performance. Three bands, each can be cut to silence.

  1. Press [TRACK 2] — load a different sample/loop, or duplicate Track 1's content
  2. Press [FUNC] + [FX1] → choose DJ STYLE KILL EQ. Press [NO]
  3. FX1 parameters:
    • HI — high band (cut/pass)
    • MID — mid band
    • LO — low band
  4. Press [PLAY]. With all 3 bands at center (no cut), audio is full-range
  5. Pull LO all the way down — bass disappears. Pull MID down — vocals/melody disappear. Pull HI down — top end disappears
  6. Performance trick: kill the LO during a buildup, slam it back in on the drop. Use scenes (Module 7) to automate this with the crossfader

Exercise 5: Combine All Three (2 min)

Build a pattern that uses everything you learned.

  1. Track 1 (drum loop): FX1 = Multi Mode Filter (LP, RES = 50, p-locked cutoff per step), FX2 = Parametric EQ (cut low-mid mud, boost high)
  2. Track 2 (bass): FX1 = DJ Kill (LO open, MID/HI cut for bass-only)
  3. Press [PLAY]. Listen to the sculpted mix
  4. Save the project: [FUNC] + [PROJ]

Exploration (if time allows)

  • Try MODE = BR (band reject / notch) — cuts a narrow band rather than passing one. Useful for de-essing or removing a specific frequency
  • Set the Multi Mode Filter MODE = PK (peak) for a resonant boost at FREQ — like a wah pedal frozen in place
  • Use an LFO on FILTER FREQ (Module 6) for hands-free filter sweeps

Output Checklist

  • I assigned the 12/24dB Multi Mode Filter to FX1 and swept the cutoff
  • I p-locked the filter cutoff on at least 3 steps
  • I used the Parametric EQ to cut a problem frequency and boost another
  • I performed with the DJ Kill EQ — pulling bands down and back up
  • I built a pattern combining filter + EQ on multiple tracks
  • I saved the project

Key Takeaways

  • Multi Mode Filter is your most-used effect — sweeps, resonant peaks, modes for any flavor (LP/HP/BP/BR/PK)
  • Parametric EQ is for tone shaping and surgical fixes — not for sweeps
  • DJ Kill EQ is for performance — pull bands down for buildups and breakdowns
  • P-locking the FREQ parameter on a filter is one of the most musical things you can do on the OT

Next Session Preview

Next: time-based effects — delay, reverb, chorus, phaser, flanger. The Echo Freeze Delay is the OT's signature effect; you'll learn the freeze trick and build a dub-style pattern.