šŸ”Š Monitor Keeper

Keep your studio monitors and speakers awake with inaudible subsonic tones
šŸ’” Install this app: Install Monitor Keeper at the bottom of the page, or use Chrome menu ā†’ "Install Monitor Keeper"
50 Hz
20 min
15 sec
Click "Start" to begin
Monitor Status: Ready (Tone Generating)
āœ… Monitor keeper is actively protecting your speakers from auto-sleep!
Activity Log
No activity yet...
ā“ How to Use & FAQ
šŸŽÆ How does this work?
This app plays a 15-second subsonic tone (below human hearing) every 1-30 minutes to prevent your studio monitors, speakers, or audio interface from auto-sleeping. Works with KRK, JBL, Yamaha, and most powered monitors.
šŸ”§ Frequency & Testing Guide
Frequency Range (10-100Hz):
ā€¢ 10-15Hz: Subsonic (inaudible to humans) - best for keeping monitors awake
ā€¢ 16-100Hz: Audible range - great for testing and troubleshooting
ā€¢ 50Hz is the default and provides a good balance

Testing:
ā€¢ Use "Test L" button to test left monitor/speaker
ā€¢ Use "Test R" button to test right monitor/speaker
ā€¢ Different frequencies help distinguish channels (A4 vs C5)
ā€¢ Monitor the activity log to confirm automatic tones are playing
ā€¢ Check the countdown timer to verify timing is accurate
šŸ”Š Enabling Background Audio
Chrome/Edge: Click the šŸ”’ icon in address bar ā†’ Site settings ā†’ Sound ā†’ Allow
Firefox: Usually works automatically
Safari: Safari ā†’ Settings ā†’ Websites ā†’ Auto-Play ā†’ Allow All Auto-Play
All browsers: Must interact with page first (click any button)
šŸ–„ļø Browser Compatibility
āœ… Chrome/Edge (Recommended) - Excellent background support
āœ… Firefox - Very good Web Audio API support
āœ… Safari - Good, may need background app refresh disabled
āš ļø Mobile browsers - Limited, works best on desktop
āš” Tips for Best Results
ā€¢ Keep this browser tab pinned
ā€¢ Don't fully close your browser
ā€¢ Test the tone first to ensure audio is working
ā€¢ 10-15Hz frequency works for most monitors (subsonic)
ā€¢ 16-100Hz is audible and great for testing
ā€¢ Bookmark this page for easy access
šŸŽ§ Individual Channel Testing
Left/Right Channel Test:
ā€¢ Click "Test L" to test left monitor/speaker only
ā€¢ Click "Test R" to test right monitor/speaker only
ā€¢ Left channel plays A4 (440Hz) for 2 seconds
ā€¢ Right channel plays C5 (523Hz) for 2 seconds
ā€¢ Verify each monitor/speaker is connected to the correct channel
ā€¢ Different frequencies help distinguish left from right
ā€¢ Use this to check your audio interface and cable connections
šŸ”§ Troubleshooting
No audio playing? Check volume, try "Test Tone Now"
Stops in background? Enable site audio permissions
Monitors still sleeping? Try lower frequency (10-15Hz) or test with audible range (50-100Hz)
Need more frequent tones? Set interval to 5-10 minutes
Wrong channel playing? Check your audio interface settings