Frequency What it generally affects

 

	What it generally affects
20 kHz	On the Soundcraft Ui24R, the 31-band GEQ is available on the Stereo Master and Aux/Matrix outputs, and the RTA can help you identify frequencies to adjust. (Soundcraft) First: don't start by cutting all 31 bands For room tuning, the goal is small corrective cuts, not making a “smile” EQ. Start with the GEQ flat (0 dB). 1. Set up the system Use: Ui24R → amplifier/DSP → speakers Put a measurement microphone at approximately ear height in the audience area, ideally around the main listening position. Before tuning: Turn off reverb/delay. Set channel EQs approximately flat. Set the Master GEQ flat. Play pink noise through the PA. Keep the volume at a realistic operating level. 2. Open the Master GEQ On the Ui24R: Master → Edit → EQ/GEQ You will see the 31 fixed frequency bands. The Ui24R also provides an RTA display on the GEQ screen. (Soundcraft) The bands are approximately: Frequency What it generally affects 20 Hz Sub-bass 25 Hz Sub-bass 31.5 Hz Deep bass 40 Hz Deep bass 50 Hz Bass 63 Hz Bass 80 Hz Bass 100 Hz Bass 125 Hz Low-mid 160 Hz Low-mid 200 Hz Low-mid 250 Hz Low-mid 315 Hz Mud 400 Hz Mud 500 Hz Body 630 Hz Body 800 Hz Mid 1 kHz Mid 1.25 kHz Mid 1.6 kHz Mid 2 kHz Presence 2.5 kHz Presence 3.15 kHz Presence 4 kHz Presence 5 kHz High-mid 6.3 kHz High 8 kHz High 10 kHz High 12.5 kHz High 16 kHz Air 20 kHz Air 3. Watch the RTA — but don't EQ every peak This is very important. The RTA shows the spectrum, but every peak you see is not necessarily a room problem. Music and pink noise naturally contain energy at different frequencies. Look for large, narrow peaks that remain consistently present. For example, suppose you see a strong, persistent peak around 250 Hz. Don't immediately cut −12 dB. Start: 250 Hz → −2 dB Listen/measure again. If the problem remains: 250 Hz → −3 or −4 dB Usually, I'd try to keep room-EQ cuts relatively modest. 4. If you hear “mud” Try these areas: 200–400 Hz For example: 200 Hz: −1.5 dB 250 Hz: −2 dB 315 Hz: −2 dB 400 Hz: −1 dB But don't automatically apply all of these. Only cut the frequencies that your measurement confirms are excessive. 5. If voices sound harsh Look around: 2–4 kHz For example, if your measurement shows a strong resonance at 3.15 kHz: 3.15 kHz → −2 dB Then recheck. 6. If the system sounds too bright Look around: 6.3–12.5 kHz Again, make small corrections rather than dropping the entire high-frequency section. 7. Be careful with low frequencies Don't use the GEQ to remove every low-frequency peak. For a PA with subwoofers, your crossover/DSP settings should handle the division between tops and subs. The Ui24R Master output also provides HPF/LPF controls that can be used for filtering/crossover purposes. (Soundcraft) 8. Use AFS2 separately The Ui24R has dbx AFS2 Automatic Feedback Suppression on the output GEQ. It uses intelligent filters to detect feedback. (Manualshelf) For a church setup, I would use: Room EQ → manual GEQ then Feedback protection → AFS2 Don't use AFS2 as a replacement for room tuning. A good starting rule For your first tuning session: Start: 31 bands = 0 dB Then make only the necessary corrections: −1 dB → −2 dB → −3 dB Avoid large boosts. If a frequency is badly deficient, the problem may be the speaker placement, room acoustics, crossover, speaker DSP or microphone position, rather than something that should be fixed with a large EQ boost. If you tell me which speakers and subwoofers you're using with your Ui24R (for example Yamaha, JBL, RCF, DZR315, etc.), I can give you a 31-band starting EQ table specifically for your church PA, including 20 Hz through 20 kHz and recommended crossover/HPF settings. For speech/voice, especially church preaching or announcements, the most important range is the midrange, where intelligibility lives. Good speech EQ starting point Frequency Adjustment Purpose 80 Hz -6 to -12 dB Remove rumble 100–120 Hz -2 to -5 dB Reduce boom 200–300 Hz -2 to -4 dB Reduce muddiness 500 Hz -1 to -3 dB Reduce boxiness 1 kHz 0 to +2 dB Voice body 2–3 kHz +2 to +4 dB Speech clarity/intelligibility 4–5 kHz +1 to +3 dB Presence 6–8 kHz 0 to +2 dB Detail 10–12 kHz 0 to +2 dB Air, if needed 15–16 kHz 0 to -2 dB Usually not important for speech