What are the acoustic properties of the space associated with forms of worship?

Sound processing of different forms of religious architecture

In many churches, churches and various other religious buildings, there are huge differences in hearing due to the construction of various religious buildings.

It is interesting to consider how the acoustic properties of the space relate to the form of worship and related musical styles. Over the years I have worked for many churches, churches and chapels, from extensive, multiple-exit cathedrals and magnificent mosques to small rooms that almost come home. I tell my teaching clients that in situations where I observe you using the space, how you use it – or how you want to use it, I can design a sound system for you or solve a sound problem.

Speech intelligibility is often the core, but often that's not the only factor to consider – it's about speech even in buildings without music. Visual impact and architectural impact seem to be higher than acoustic and sonic integrity. Ironically, perhaps the extensive acoustic characteristics of religious buildings are enough to mess things up and obscure the importance of having good acoustics.

As shown in Figure 1, churches and chapels exhibit the widest range of acoustics, with reverberation times ranging from about one second to three seconds. In fact, they actually exceed this ratio. Many religious buildings have mid-frequency reverberation times of six seconds or more. So why is there such a big difference? What makes a church need a 6:1 sound effect while the music is only 2:1 or 2.5:1? Basically, there are two reasons as described below.

First, acoustic effects are influenced by the size and structure of the building; Second, to a certain extent, acoustic effects depend on the nature of the religion and/or the form of worship. It was only in the last 50 to 60 years that the acoustics of space preceded that sound effects that essentially defined the form of worship. For example, when many European cathedrals were built between 800 and 1000,<> years ago, their sheer size and inherent long reverberation time meant any significant distances that were not clear. In addition, acoustic properties also mean that the tempo of the music must be relatively slow, so notes or phrases disappear completely before the next note or phrase – otherwise, they cannot be distinguished and they will be together.

The same goes for speech, but the time between words should be extended accordingly. Some forms of choral music – such as chanting – are of course created using long-term reverb, allowing sounds to flow into each other. To make this point in this light, I map some of the reverberative features of English cathedrals, namely the privilege of dominating the measure for years.

As shown in Figure 2, the average reverberation time is about 4.5 seconds. Although the mid-frequency reverberation time in one of the buildings peaked at nearly 6 seconds, "modern religion" and worship forms cannot be used in the context of such reverberation. It works in the middle because words or sounds have different meanings and require greater influence. Contemporary music is also faster and completely unsuitable for this acoustic environment. However, these long reverberation times are ideal for organ and choral music, as well as carols. The latter is usually best for not opening, but there is also room for reverb.

The longest cathedral reverberation time I measured was the modern cathedral, about 9.5 seconds. There are also some interesting sound focus issues, but it sounds amazing with music on the right. Technically, it's barbaric, and the more common reverberation time is a killer of verbal intelligibility. However, with the right sound system design and clear sound, even this acoustic anomaly can eventually be eliminated.

At the same time, mosques are another form of religious architecture that often presents challenging acoustics. Figure 3 shows the characteristics of the reverberation time of many large mosques. It is clear from the attached drawings that there is no such thing as a "typical mosque acoustic feature". Small prayer halls (e.g., 100 to 200 people) usually have a reverberation time characteristic below the red curve at the bottom and are relatively benign.

The religious acoustics on the smaller scales are relatively rigid, i.e. more modern forms of worship, such as those that include those prescribed by the praise ring. These spaces are actually theaters or lecture halls, so their reverberation time should not exceed about 1 second, unless they have a few hundred seats.

Figure 4 shows some measurements in several buildings belonging to the same confidence. Religion is mainly based on speech, but there are also some traditional congregations singing. On the 1.35-second blue curve, the reverberation time is a bit too long and feels very active. While the standard distributed cap-and-pop speaker system works, it's pretty close to the acceptance margin (and feedback!). ）。 The lower red and green curves measured in the building, although very silent and difficult to sing, exhibit excellent speech intelligibility. The orange curve is basically optimal at about 1.1 seconds: active enough singing and well controlled so the sound system can provide a lot of gain before feedback. The reverberation time of the purple curve is about 0.9 seconds. The mid-range is acceptable, but it can be raised if the bass rise is already better controlled.

Finally, Figure 5 shows the reverberation time of a modern medium-sized church, which can hold about 800 people. The reverb time is a bit long, making the band a very lively space, and the sound can sometimes become a little blurry. (Feedback is often a challenge as well.) As I stated last March, sound effects are not only reverberation time, but also a lot of things. As with many things in architecture and acoustics, details determine success or failure everywhere.

Figure 1: Optimal reverberation time and architectural purpose for various activities.

Figure 2: Reverberation time at the cathedral.

Figure 3: Typical reverberation time characteristics of large and medium-sized mosques.

Figure 4: Reverberation time characteristics of different churches of the same faith.

Figure 5: Reverberation time characteristics of a religious band in a modern baptist church.

Sanway Audio also offers different audio speakers or line array systems for different churches. Project case. DASWELL CS64 6x4" column speaker, CS44 4x4" column audio speaker and SF12 single 12" full-range speaker are installed in churches to provide clean sound.