Excluded sound device on EDSAC

Maurice Wilkes' 'The EDSAC Computer' appeared in Joint AIEE-IRE Computer Conference (Dec.10~12 1951) reveals that EDSAC, the world's second stored-program based digital computer, also had a sound device for alarming accumulator's overflow.

Another checking device included in the EDSAC in its early days was an alarm which sounded when the capacity of the accumulator was exceeded. This, however, turned out to be more trouble than it was worth, since there are a good many occasions, particularly when orders are being modified, when the programmer wishes to perform some operation which will necessarily involve an overflow in the accumulator. Another disadvantage was that the alarm tended to get switched off during testing operations, and not switched on again, so that it failed to serve the purpose for which it was intended. In consequence of these objections the device was removed from the machine. (p.80)

I think it was the first case in the history of computers that people decided to exclude the sound feature. His paper proves it might be painful in some cases on very early computers. Comparing to EDSAC, now we can regard BINAC, Ferranti Mark I and CISRAC, as the successful cases for implementing it effectively.