THE ACOUSTIC ANALYSIS IS BASED ON THE FOLLOWING BUILDING DATA:

All analyses DO take into account the cancellation and amplification effects of the reflections off of the room surfaces, as well as the absorption of various frequencies by the room surface materials and the people in the room.   They also take into account a default average of 40 dB room noise due to HVAC systems, exterior noise and audience noise.

The analyses cover a 7 octave range - 200Hz to 20KHz.

While we were able to achieve only an overall GOOD / FAIR rating, this is significantly better than the POOR / Unusable rating of the original system.   Our speaker selections and placements were limited by several factors.   The church wanted the system to be as visually unobtrusive as possible.   This necessitated a small speaker, concealed in a cabinet that would blend with the church's architecture.   Also, the church did not want any acoustic treatments applied to the room's surfaces.

St. Rita Aiming Plot
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This plot shows the aiming points and coverage patterns for the system.

St. Rita SPL Plot
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This plot represents the Total SPL (Sound Pressure Levels) distribution in decibels (dB) over the entire room.   This analysis takes into account the cancellation and amplification effects of the reflections off of the room surfaces.

A drop of -3 dB or less over the coverage area is considered optimal, a drop of between -3 to -6 dB is acceptable, more than a -6 dB drop is unacceptable.

As the plot demonstrates, the SPL are evenly distributed over the entire room; ranging from a High of 94 dB to a Low of 92 dB (overall).

The drop in this room is -2 dB overall, which is optimal.

St. Rita ALCONS Plot
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ALCONS Scores:

• Under 3 % = Excellent - Suitable for complicated messages and music.

• 3.1 % to 7.0 % = Very Good - Adequate for less complicated messages, or trained speakers.

• 7.1 % to 11.0 % = Good - Suitable for simple messages and well-trained speakers.

• 11.1 % to 15.0 % = Fair - Adequate for simple messages with expert speakers and trained listeners.

• 15.1 % to 20 % = Poor - Limit of acceptable intelligibility for simple messages and expert speakers and listeners.

• Over 20 % = Unusable - Unintelligible even for expert speakers and listeners.

The ALCONs scores for this room range from 7.97 % to 13.41 % overall, with the majority of the seating area being in the 8.00 % to 10.00 % range.

This is considered to be a GOOD rating.

St. Rita RASTI Plot
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RASTI Scores:

• 0.75 to 1.00 = Excellent - Suitable for complicated messages and music.

• 0.65 to 0.74 = Very Good - Adequate for less complicated messages, or trained speakers.

• 0.55 to 0.64 = Good - Suitable for simple messages and well-trained speakers.

• 0.45 to 0.54 = Fair - Adequate for simple messages with expert speakers and trained listeners.

• 0.30 to 0.44 = Poor - Limit of acceptable intelligibility for simple messages and expert speakers and listeners.

• Below 0.29 = Unusable - Unintelligible even for expert speakers and listeners.

The Rasti scores for this room range from 0.46 to 0.55 overall, with the majority of the seating area in the 0.47 to 0.52 range.