Technology & buying guide · 5 min read
Microphone Feedback: Why It Happens and How to Stop It
The howl explained — speaker placement, microphone choice, gain structure, EQ and feedback suppressors, in the order that actually works.
Feedback is a loop: the microphone hears the loudspeaker, the loudspeaker plays it louder, and the sound grows until it howls. Fixes work best in a specific order.
1. Put the speakers in front of the microphones
Main speakers should be ahead of the stage line and aimed at the audience, never behind or beside the presenter. This single change fixes most halls.
2. Use the right microphone, close to the mouth
Directional (cardioid or hypercardioid) microphones such as the itc TS-331 reject sound from behind. A microphone 5 cm from the mouth needs far less gain than one at 30 cm — less gain, less feedback.
3. Set the gain structure, then EQ
Set input gain for the loudest speaker, keep the master at a sensible level, and only then use EQ to notch the few frequencies that ring in the room.
4. Add a feedback suppressor
A dedicated suppressor (itc TS-224D / TS-224DX) automatically places narrow filters on ringing frequencies — ideal for halls operated by non-engineers. It is the last step, not the first.
5. Fewer open microphones
Every open microphone adds to the loop. Mute mics that are not in use, or use an automatic mixer.
Recommended equipment
| Role | Model | Why |
|---|---|---|
| Feedback suppressor | itc TS-224DX | Automatic notch filters |
| Directional mic | itc TS-331 | Hypercardioid rejection |
| Processor | itc TS-3400MIX | EQ and system control |
Frequently asked questions
Will a feedback suppressor alone fix our hall?
It helps, but speaker placement and microphone technique matter more. Use it as the final layer.
Want an engineer to check your plan?
Free site survey, system design and an itemised quotation from our engineers.