Technical rehearsal

The technical rehearsal or tech rehearsal is a rehearsal that focuses on the technological aspects of the performance, in theatrical, musical, and filmed entertainment. Tech rehearsals generally are broken down into four types: dry tech rehearsals, tech rehearsals, pick-up tech rehearsals, and paper tech. Their purpose is to fully test all of the technology being used in the performance (lighting, sound, automation, special effects (e.g. pyrotechnics), etc.) to diagnose and prevent mistakes from occurring during the actual performance. They also allow the designers to see how their designs will impact each other (i.e. how the color of a light might affect the look of a costume), and to make final changes. Tech rehearsals are to make sure during the show all tech items will run smooth. The dry tech is essentially a rehearsal without the performers. It is a period, usually lasting multiple hours, where each designer and department head runs his or her segment of the production. It is also a chance for the tech crew who will operate the equipment to become familiar with the flow of the performance. Usually it consists of the lights being cued in sequential order, fixing any problems along the way such as brightness, angle, framing, or position. Then a sound check is initiated to check the levels of the music, sound effects, or microphones to be used during the performance. Changes are made as necessary to correct volume, pitch, or feedback problems. Lastly, for stage shows, the fly rigs or battens are tested for weight and accuracy of cueing with sound and lights. If there are moving set pieces, the crew will test their operation and mechanics (if they are automated) and practice their movement, flow, and position on and offstage. There may be an extra step for particularly effect-intensive productions, such as film, TV, or Broadway-style stage shows, where the crew tests any special effects that require systems such as rain, fire, or explosions. When these effects are completed to the director's and production designer's satisfaction, the crew is ready to move onto the tech.