DI8-24 e DO-1616 na EXPO'98 em Lisboa

EXPO'98, the last Universal exhibition of the Century took place in Lisbon, Portugal. This gigantic exhibition was entirely devoted to sea themes. One of the exhibition goals was to make known to the world Portugal's decisive pioneering role in the Discoveries which led to the process of European overseas expansion in the 15th and 16th centuries. EXPO'98 opened on 22 May and closed on 30 September 1998, with the participation of more than 140 countries and an expected number of visitors of 8.5 million. The exhibition took place on a 60 hectare site around Olivais dock, an huge lake where 10 football pitches would fit.

Apart from the regular pavilion exhibits there was a lot of animation in the exhibition sidewalks and gardens. 16 outside stages boosted music performances constantly, ranging from classic to rock and traditional music styles. These performances of course were the object of on-site sound reinforcement, as well as sometimes beinge broadcasted. The need has thus, since the exhibition was sought, arise to process stage signals so as to allow their accurate distribution to several destinations, while preserving their quality.

To answer those requirements, Acutron, on the basis of requirements set up by the responsible for the electroacoustics Mr. Daniel Léon, created the DI8-24 and DO-1616 microprocessor-controlled signal distributors. Those were respectively a 8 by 3 input and an 16 by 16 output distributor. They could be controlled by soft keys or by an external computer via an RS-485 serial interface. The input distributor took the stage signals, amplified those by a programmable gain factor and splitted it through 3 different outputs offering at the same times programmable and individual output ground lifts to help alleviating potential ground problems. It is worth to mention that equivalent input noise level of this device was in the order of -130dBu, just to give the reader an idea of the stringent requirements we had to meet.

Once a set-up for a show has been made, it could be stored into one of the 14 internal EEPROM memories, to be recalled instantly when the show is back again to the particular stage.

DO-1616 was an output disrtributor with a built-in monitoring system alowing the on-stage sound quality evaluation. The device was equiped with programmable ground cuts.

Big events like the EXPO'98 often require that new developments are made in a hurry. This one was not an exception. The development of the DI-824 and the DO-1616 was made from scratch in less than one month, hardware and software, in the development department of Acutron. The production started immediately allowing the first equipment to be delivered just before exhibition start, within a less than 2 month record time. Meanwhile, Acutron was in parallel delivering all the cabling necessary to set up those 16 stages, which by itself was already quite a gigantic job. To give the reader a faint idea of the work scale, it will be enough to say that for example about 20Km of microphone cable were processed.

The solution found by Acutron answered to the original EXPO'98 requirements while introducing the programmability and the availability of scenarios stored in the equipment. It thus adapts closely to the lively character of the performances that took place daily at the Lisbon exhibition. About 60 DI-824 and 30 DO-1616 were in use at the EXPO'98.

We profit to express our thanks to Mr. Daniel Léon for the cooperation showed during all phases of this work and our deepest appreciation to be associated with such an ambitious and challenging project as EXPO'98 was.