Broadcast and Recording Studio Construction and Technical Considerations. By Jesse Role, Ph. D. TM - Electronics Chairman, Department of Technology University of Eastern Africa, Baraton. Topics Covered. Studio design and size Internal and external e nvironment Lighting consideration
Jesse Role, Ph. D. TM - Electronics
Chairman, Department of Technology
University of Eastern Africa, Baraton
• Number of desired studios
• Acoustic treatment
• Choice of acoustic material
• Choice of studio equipment
• Choice of transmitting equipment
The size and shape of a room determine its natural resonances - often called room modes.
There are a few "ideal" ratios of room height, width, and length that professionalstudio designers agree should be used if possible. Three of these ratios, developedby L.W. Sepmeyer, are shown in the Table .
Symmetry matters! In a typical stereo mixing room, the loudspeakers are spaced equally from the walls and corners, and form an equilateral triangle at the mix position. The arrangement shown on the left is better than the one on the right because it's more symmetrical within the room. The layout on the right also suffers from a focusing effect caused by the wall-wall junction behind the listener.
Please understand that acoustic treatment as described in this lecture is designed to control the sound quality within a room.
There are four primary goals of acoustic treatment:
1) To prevent standing waves and acoustic interference from affecting the frequency response of recording studios and listening rooms;
2) to reduce modal ringing in small rooms and lower the reverb time in larger studios, churches, and auditoriums;
3) to absorb or diffuse sound in the room to avoid ringing and flutter echoes, and improve stereo imaging; and
4) to keep sound from leaking into or out of a room. That is, to prevent your music from disturbing the neighbors, and to keep the sound of passing trucks from getting into your microphones.
The simplest type of diffuser is one or more sheets of plywood attached to a wall at a slight angle, to prevent sound from bouncing repeatedly between the same two walls. Alternatively, the plywood can be bent into a curved shape, though that is more difficult to install. In truth, this is really a deflector, not a diffuser, as described in more detail below. However, a deflector is sufficient to avoid flutter echoes between parallel surfaces.
The higher frequencies (top) are absorbed well because their velocity peaks fall within the material thickness. The lower frequency at the bottom does not achieve as much velocity so it's absorbed less.
rigid fiberglass that is two inches thick has an absorption coefficient of 0.17 at 125 Hz
Possible factors creating noise
• Heat and Dust
• Power fluctuations
• RF reflection – Mismatch due to
– improper antenna
– improper tuning of the antenna
– loose connections between the transmitter and antenna
– Inbuilt protection (fold back)
– lightning arrester
– low resistance earth pit