Some are long, some are flat: there are some microphones which deviate from the standard, at least in terms of their design. Gooseneck microphones are almost symbolic for announcements and microphone stations. However, why do we have these 2 versions and what are their advantages? This guide will help you to communicate even better as an expert planner, integrator or installer.
Boundary microphones are flat microphones which are placed directly on reflecting surfaces, e.g. tables or walls. They use the behaviour of sound waves at the boundaries to pick up the sound as clear as possible. At the same time, they minimise unwanted reflections and comb-filter effects. This results in a clear and natural sound if placed at a good position and with the respective quality.
Boundary microphones are often of a particularly flat design. Thus, they allow for a flush integration into walls and on desktop surfaces. Therefore, boundary microphones are particularly well-suited to meet comprehensive architectural and aesthetical requirements. Furthermore, many boundary microphones feature integrated or concealed cable ducts. This allows for a clean and unobtrusive installation. This is a particular advantage in conference rooms where cable clutter looks non-professional. However, cables could also get in the way in spiritual surroundings such as churches and mosques.
Due to their design, boundary microphones can theoretically cover a wide area and thus ensure a consistent and comprehensive sound pickup, even in large rooms. The reason for this is that boundary microphones use the reflection of sound waves on smooth surfaces to pick up the sound. This results in a natural amplification of the sound. Therefore, several speakers can simultaneously be picked up in conference rooms without having to use a separate microphone for each one. Or to put it another way: 1-2 microphones are sufficient at a large conference desk to pick up each speaker at the table. Many boundary microphones feature a hemispherical polar pattern which picks up the sound from a wide area in front of the microphone. This is also particularly useful in situations where several people sit around a table and speak.
This is as far as the theory goes. In practice, it is vital where the boundary microphone is placed in order to pick up a usable sound from an area as large as possible.
Boundary microphones pick up the sound at close range because they are positioned directly on reflecting surfaces. This reduces the risk of passing the sound from the speakers back to the microphone and thus causing acoustic feedback. A phase coherence between the direct sound and the sound to be reflected is also created by placing it on a reflecting surface. This allows for a significantly clearer sound of the picked-up signal and thus minimises unwanted feedback effects. Boundary microphones are designed to minimise sound reflections from walls and ceilings which are at a distance. Otherwise, it may cause phase cancellations and comb-filter effects.
Conference rooms with long reverberation time:
Application: large conference rooms or assembly halls with large areas of glass and hard surfaces.
Challenge: long reverberation time which affects the speech intelligibility.
Solution: placing boundary microphones in the middle of the conference table to ensure a direct sound pickup and use reflections from the table surface. This reduces the reverberation and improves speech intelligibility.
Stage performances in theatres:
Application: theatre stage for performances or presentations.
Challenge: pickup of dialogues and noise on the stage without the visibility of microphones.
Solution: placing boundary microphones at the edge of the stage or integrate them into the props. This allows for a clear pickup of dialogues and ambient noise without a visible microphone or limitations to your mobility.
Courtrooms:
Application: courtrooms for trials and hearings.
Challenge: consistent pickup of statements of everyone present without having distracting microphones on the tables.
Solution: installation of boundary microphones on the tables of the judge, defendant, lawyers and witnesses. The microphones ensure a consistent and unobtrusive sound pickup. This enhances acoustics and does not affect the visibility.
Position your microphone on a smooth and reflecting surface, e.g. conference table, stage or a wall. These surfaces increase the sound and minimise reflections.
Place the microphone as close as possible to the sound source to be amplified. This ensures a clear and direct sound pickup.
The microphone should be positioned in the centre of the room if several speakers are used to pick up every speaker equally.
Use several boundary microphones to cover larger areas und to ensure a consistent sound pickup.
Pay attention to room acoustics and place the microphone in a way to minimise reflections from walls or ceilings.
Avoid placing it on soft or sound-absorbing materials, e.g. carpets or fabrics. These surfaces attenuate the sound and affect the microphone performance.
Do not place the microphone near speakers to avoid acoustic feedback
Do not cover the microphone with objects, e.g. papers, books or decorations. It blocks the sound and affects the quality of the sound pickup.
Avoid an uneven distribution of microphones to ensure that all areas are evenly covered.
Avoid placing the microphone in areas with a high level of background noise. This may affect the quality of the sound pickup.
The characteristic design and flexibility are typical for gooseneck microphones. The flexible neck allows for a precise alignment of the microphone to the sound source (e.g. a speaker). This ensures an optimum sound pickup. These microphones are perfectly suited for lecterns, individual places at conference tables, interpretation cabins and similar applications where a direct and precise sound pickup is required.
The flexible neck of a gooseneck microphone is often made of robust and flexible materials, e.g. metal alloy which allow for a precise alignment. These materials provide great flexibility. You can even be more creative: the microphone can be aligned towards any sound source required, not just the speaker who is sitting right in front of the microphone. On the other hand, gooseneck microphones are designed exactly for this purpose because the polar pattern is another advantage of this long-necked microphone.
A lot of gooseneck microphones feature cardioid or supercardioid polar pattern. This pattern allows for the microphone to pick up the sound mainly from the direction of the speaker while suppressing background noise as much as possible. This is a major advantage in loud surroundings or if several discussions take place at the same time. By the way: when talking closely, the lower vocal range is increased which results in a warmer and fuller acoustic tone. Expert planners can use the well-aligned gooseneck microphone and take advantage of this effect to improve speech intelligibility and presence. Otherwise, it is good to keep a distance of 2 hands between speaker and gooseneck microphone as a guideline.
Gooseneck microphones are designed for frequent use in demanding surroundings. Their design shows impressive durability and resistance. They are usually very easy to use. High-quality materials, e.g. stainless steel and reinforced plastics ensure a long service life. The microphones often feature shock-proof and vibration-absorbing components to minimise mechanical noise from the lectern. Integrated or removable cables with robust plug-in connectors ensure reliable signal transmission and easy maintenance. High-quality shielding prevents electromagnetic interference which may otherwise affect the audio quality.
Podium discussions in auditoriums:
Application: podium discussions with several speakers in auditoriums or large lecture halls.
Challenge: individual speakers require a clear sound pickup and a reduction of background noise at the same time.
Solution: placing gooseneck microphones on the podium desks to align them directly with the speaker. This ensures a clear sound pickup of the vocals and minimises interference from the audience.
Educational institutions
Application: lectures and presentations in universities and seminar rooms.
Challenge: to ensure speech intelligibility for large groups and sound pickup for digital recordings.
Solution: application of gooseneck microphones at the lecterns for a direct sound pickup of the lecturer. The flexibility of the microphones allows for exact positioning and guarantees a perfect sound pickup.
Religious ceremonies in houses of worship:
Application: sermons and lectures in churches and other religious institutions and houses of worships.
Challenge: to pick up the voice of the preacher and reader, while simultaneously reducing echo effects in large rooms with a strong reverberation effect.
Solution: application of gooseneck microphones at the altar or lectern. The microphones can flexibly be aligned to pick up the voice directly and minimise background noise which improves speech intelligibility throughout the entire house of worship.
… we used both gooseneck microphones and boundary microphones in the context of religious institutions. Hence, in this case, the combination is the perfect choice:
1. Careful positioning and alignment:
Boundary microphones: place these microphones on a flat and reflecting surface, e.g. altars or choir platforms. Make sure not to block them with other objects.
2. Level matching and mixing:
Use a mixer to balance the levels of the different microphones and create a well-balanced sound mix. Please ensure a high speech intelligibility of the speakers, while providing a pleasant environment with the general surround sound.
3. Acoustic adjustments:
Use boundary microphones if you require an unobtrusive microphone solution. They are placed on reflecting surfaces and provide a wide coverage with minimum reverberation effect. Ideally suited for conference rooms, stages and courtrooms which require a consistent sound pickup and pleasant appearance.
Choose gooseneck microphones if you require perfectly aligned voice recordings and a flexible direction to individual speakers. They are perfectly suitable for podium discussions, lectures and religious ceremonies where a high speech intelligibility and reduction of background noise is essential.
