It really shows what we have on this planet. The diversity. The technology. Emotions. Languages. Maybe not everything, but this is more like a teaser for a movie. It shows just a little bit. To know everything, you'll have to come and see for yourself.

The funny thing is that many to the sounds near the end are no longer commonplace. The sound of jets has changed (only fighterjets sound like that and you don't want to send that into space if the message is peace and love), propellerplanes are rare, trains are electric and no longer sound like that and the large cruisers are diesel driven and only the horn has remained the same. I also heard a horse and carriage and an oldfashioned rocket. It not only shows the space dwelling creatures what we had back then and have had further back in the past. It is also a recording of how the world changed in these 30 years.

Still makes me wonder what I would pick. Maybe I would include the sound of a data center...

From Wikipedia:

The Voyager Golden Records are phonograph records which were included aboard both Voyager spacecraft, which were launched in 1977. They contain sounds and images selected to portray the diversity of life and culture on Earth, and are intended for any intelligent extraterrestrial life form, or for future humans, who may find them. The Voyager spacecrafts are not heading towards any particular star, but Voyager 1 will be within 1.6 light years of the star AC+79 3888 in the Ophiuchus constellation in about 40,000 years.[1] As the probes are extremely small compared to the vastness of interstellar space, the probability of a space-faring civilization encountering them is very small, especially since the probes will eventually stop emitting any kind of electromagnetic radiation. If they are ever found by an alien species, it will most likely be far in the future as the nearest star on Voyager 1's trajectory will only be reached in 40,000 years. Carl Sagan noted that "The spacecraft will be encountered and the record played only if there are advanced space-faring civilizations in interstellar space. But the launching of this 'bottle' into the cosmic 'ocean' says something very hopeful about life on this planet."[2] Thus the record is best seen as a time capsule or a symbolic statement rather than a serious attempt to communicate with extraterrestrial life.