Smart Jam is one of the most central features of the Spark app — it lets you jam with AI-generated drummers who listen to your playing and build a backing track around what you play.
Tutorial video
Regular Smart Jam
Choose from 4 AI drummers, each with a distinct style. Each drummer listens to your chords / dynamics and generates a backing track that follows a song structure.
To use Smart Jam
- Connect both Tone Control and Bluetooth Audio of your Spark amp to your device.
- Go to the Music page of the app.
- Tap into Smart Jam to select a drummer.
*Microphone permission is required — chord detection and real-time excitement detection (Jarvis only) use your device's microphone.
Once you've selected your drummer — step-by-step (7 steps)
-
Tap in your desired tempo by tapping the Tap button.
-
Place your device at least 0.5 meters (1.8 feet) away from your Spark's speakers, with the microphone facing the Spark. This prevents your device's microphone from clipping during recording.
-
Tap Start — you'll be given 4 clicks at your desired tempo. If you don't hear the clicks, make sure your device is connected to Spark's Bluetooth Audio and that both your device's volume and Spark's music volume are turned up.
-
After the 4 clicks, the drummer starts listening. Start playing a chord progression on the next beat. All Smart Jam drummers currently support 1 chord every 2 beats. Watch the red bar at the bottom — if the red line goes across the entire screen, your device's microphone is clipping and the results may not be accurate.
- You can play up to 8 bars. If your chord progression is only 4 bars, tap the checkmark button when it's highlighted to skip the last 4 bars.
- Once the analysis is complete, select from 6 tracks that the drummer has created. Swipe left or right to scroll through and preview them.
- Once you've selected a track, you'll be taken to the Jam Track page to start jamming.
Real-time Jam (Jarvis)
Jarvis is a rock-style drummer who listens to your dynamics and feel while you're playing, and provides real-time feedback with louder or softer hits, and more simple or complex grooves. Unlike the other drummers, Jarvis only listens to 4 bars of chords.
For the best real-time jamming experience, observe the top red bar and do the following calibration during your first playthrough with Jarvis:
- At your loudest playing level, the top red bar should almost reach maximum. If it hits maximum, your device's microphone is clipping — turn down the volume of your instrument or music.
- At your quietest playing level, the top red bar should hit roughly 3 red blocks. This min–max range gives the best dynamic detection.
- Make sure your guitar is louder than the backing track. Aim for a 2:1 to 2:1.5 volume balance (guitar to backing track). This makes it easier for Jarvis to detect your playing.
Quick tip: mess around with different tones while you're playing. Only using a high-gain or only a clean tone won't create the most dynamic experience — Jarvis responds best to variation.
Smart Jam Settings
Change the tempo, toggle the bass of the backing track on and off, and transpose the current chord progression in the Smart Jam settings menu. To access it:
- For Jarvis, tap the settings icon on the bottom left of the Jam Track page.
- For Dave, Sharon, and Charles, tap the settings icon at the top right of the Jam Track page.
- For Charles, you can also choose between straight or shuffle feel in the settings menu — only applies to new tracks, not saved tracks.
Edit Chords
You can edit the chord progression once you've entered the Jam Track page.
Jarvis
- Tap the "Edit Chords" button on the bottom of the Jam Track page.
- Navigate the page by tapping on the chords on the timeline or using the arrows, then select your desired chord from the picker below. Tap "Apply" on the top right to apply the change. The backing track will restart with your new chords.
Dave, Sharon, and Charles
- Pause the backing track by pressing the pause button on the bottom right. Then long-press a chord on the timeline. Your selection will appear on screen — drag the left and right edges to edit multiple groups of chords at once.
- Once you've selected the chords, tap "Edit Chord" when it appears on screen.
- Select your chord of choice. Tap "Apply" to change the chord in the selected section only, or "Apply to All Parts" to change it in every section of the song (Verse, Chorus, and Bridge).
Save Your Smart Jam Track
- To save your Smart Jam track, make sure you're logged in to your Positive Grid account. If not, tap the save button to trigger the login prompt.
- Once logged in, tap the save button on the top right for Dave / Sharon / Charles, or the bottom right for Jarvis.
- The Save menu appears — select a slot. If all slots are full, you'll be asked to overwrite an existing track.
- To load a track, go to Menu → "Saved Songs" → "Jam Tracks" tab. Tap a track to load and start jamming. You can also rename tracks and clear tracks from a slot.