First a YouTube compilation of tenor Michael Spyres singing high notes – some of which can only be heard by dogs. Spyres has mastered mixing, without a noticeable break, all the registers that a tenor can use. His highest notes from operas written before tenors sang high Cs and above from the chest employ voix mixte and supported falsetto. What’s really remarkable about his technique is the strength of his middle and lower notes. As long as his current vocal state persists he can sing just about anything written for a tenor.
Below both YouTubes presented here is a link that will allow to view or download either video should the YouTube files go walkabout.
The second video, posted by Spyres himself about 12 years ago shows that Caruso wasn’t the only tenor to masquerade as a bass. It’s self explanatory.
Finally, here’s Enrico Caruso’s singing the bass aria from the 4th act La Boheme – Vecchia zimarra. Recorded in 1916. It was not released during the tenor’s lifetime; he said it wouldn’t be fair to the basses. He sent it to friends as an unusual gift. The bass Andrés De Segurola lost his voice during an 1913 performance of the opera in Philadelphia. Caruso, who knew this might happen as De Segurola had told him he had a sore throat, had the bass mouth the words while he sang the aria. Remarkably, no one seems to have noticed that Rodolfo was singing Colline’s music. His recording is in the original bass key. This is the ultimate in dark voiced tenors or it was until Spyres appeared.