Question 1

How do I set delays for a distributed speaker system?

Accepted Answer

In a distributed system (multiple ceiling speakers or column speakers covering different zones), each zone must be delayed to match the arrival of the main system. Procedure: identify the boundary of each zone (where the main system coverage transitions to the distributed zone). At each boundary, measure the main system delay. Set each distributed speaker delay to match the main system delay at its coverage boundary. Add 5-10 ms of additional Haas delay to ensure the main system precedence. Work from front to back: the first zone matches the main, each subsequent zone matches the previous zone at their shared boundary. SonaVyx measures delays at each boundary position and helps you calculate the required electronic delay for each zone.

Question 2

What is a delay tower and how do I align it?

Accepted Answer

A delay tower is a speaker cluster positioned in the audience area (typically 20-40 m from the stage) to reinforce the main system for listeners too far from the stage. Alignment: measure the main system delay at the delay tower position. Set the delay tower electronic delay to match the main system arrival plus 5-15 ms Haas offset. The delay tower level should be 6-10 dB below the main system level at the overlap zone so the audience still perceives the main as the source. Verify at multiple positions in the delay tower coverage area: the combined response should be smooth without audible echo or comb filtering. For large outdoor festivals, multiple delay towers at increasing distances each need progressively longer delays. SonaVyx measures the required delay at each tower position directly.

Question 3

How do I handle delay for under-balcony speakers?

Accepted Answer

Under-balcony areas are challenging because the balcony blocks high-frequency sound from the main system while low frequencies diffract around it. The under-balcony speakers must fill the high-frequency gap without creating a disconnect with the low frequencies still arriving from the main system. Set the under-balcony delay to match the main system arrival at the under-balcony listening position. High-pass the under-balcony speakers at 200-400 Hz to avoid duplicating the bass that already reaches the audience from the mains. Level the under-balcony speakers to be 3-6 dB below the main high-frequency level so they fill without dominating. SonaVyx individual and combined measurements verify that the under-balcony fills seamlessly blend with the main system.

Question 4

What is zone overlap and how do I handle it?

Accepted Answer

Zone overlap is the area where two speaker zones both provide significant SPL. In the overlap zone, the sounds from both speakers combine and can interfere. Managing overlap: ensure time alignment at the overlap boundary (measure delay of both speakers at the boundary). Set levels so neither speaker is more than 6 dB above the other in the overlap zone (this limits comb filter depth to 6 dB). Aim speakers to minimize overlap width (tighter coverage patterns reduce the overlap area). Accept that the overlap zone will have some comb filtering due to the different speaker positions — this is unavoidable with any multi-speaker system. SonaVyx measurements in the overlap zone show the combined response and the comb filter depth, letting you optimize the overlap width and level balance.

Question 5

How do I calculate delays for a ring of delay speakers around a large room?

Accepted Answer

For a ring configuration (speakers around the perimeter, all fed from the same source): start with the speaker farthest from the main system and work inward. Each speaker should be delayed to match the arrival of its nearest neighbor in the chain, plus 2-5 ms of Haas offset. For a room with the main system at one end: measure the main system delay at each perimeter speaker position. Set each speaker delay to the main system delay at its position. Alternatively, use the distance from the main system to calculate approximate delays (distance / 343 = delay in seconds), then fine-tune with measurement. In very large rooms, the cumulative delay around the ring can exceed 50-80 ms. Listeners in the center hear sound from the nearest speakers, which arrive at different times. SonaVyx helps optimize by measuring at both perimeter and center positions.

Question 6

Should I use equal-level zones or tapered zones?

Accepted Answer

Tapered zones, where each zone is slightly quieter than the one closer to the source, generally produce more natural sound. Equal-level zones can create an artificial surround effect where the audience perceives sound from all directions equally. Tapered zone approach: the main system is the loudest, each subsequent zone is 3-6 dB quieter. This maintains the perception that sound originates from the main source while the distributed speakers provide support. Level tapering also reduces the severity of comb filtering in overlap zones because the level difference reduces the depth of interference. SonaVyx SPL measurements at each zone verify the level tapering is correct, and the transfer function in overlap zones confirms that the comb filtering is within acceptable limits.

Question 7

How do I align ceiling speakers in a conference room?

Accepted Answer

Conference room ceiling speakers are typically distributed to provide even coverage. For a speech reinforcement system with a talker microphone: delay each speaker to match the direct sound from the talker. The direct sound from the talker reaches the closest listeners immediately, so the nearest ceiling speaker should have minimal delay (just the system processing latency). Speakers farther from the talker need increasing delay to match the talker direct sound arrival at their coverage area. For a playback-only system (no talker microphone): align all speakers to a reference point (typically the main entry or the head of the table). SonaVyx measures the delay from each speaker at its primary coverage position and calculates the required settings. The crosshair readout on the IR helps identify the exact arrival time.

Question 8

What problems occur if delays are set incorrectly in a multi-zone system?

Accepted Answer

Incorrect delays cause several audible problems depending on the error magnitude. Less than 5 ms error: comb filtering audible as tonal coloration (like talking through a cardboard tube). The effect is frequency-dependent and position-dependent. 5-30 ms error: the sound becomes muddy and unclear, like excessive reverberation. Speech intelligibility drops noticeably. The audience may perceive a slight echo. 30-50 ms error: a distinct pre-echo or slap-back echo becomes audible, where the wrong speaker arrives first and the main system arrives as an echo. Above 50 ms: a clear separate echo that sounds like two distinct sources. SonaVyx impulse response at the listening position shows multiple arrivals, making it immediately obvious if delays are incorrect. The delay finder quantifies the error for each speaker.

Multi-Zone Delay Alignment: Distributed Systems, Delay Towers, and Zone Management

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