The "Real" disco era depends on one's opinion. Though the books generally say 1973-1982 but it differs with individuals and their experiences or knowledge or what they "class" as disco music.
What I call disco, half of it goes under generally as funk. Here are some real early songs that are generally classed as funk/R&B but I call disco:
Kool & The Gang - Love The Life You Live 1971
Curtis Mayfield - Move On Up 1970
Curtis Mayfield - If There's Hell Below 1970
Curtis Mayfield - Beautiful Brother Of Mine 1971
Curtis Mayfield - Get Down 1971
Isaac Hayes - Theme From Shaft 1971
Isaac Hayes - Theme From The Men 1972
Edwin Starr - Time 1970
Steam - Na Na Na Hey Hey Kiss Him Goodbye 1969
Intruders - She's A Winner 1972
Bar-Kays - Son Of Shaft 1972
Well at least these songs are the forerunners of what is later known as disco.
Anyhow I certainly can't disregard 1973-1975 from the "Real" disco category especially with songs like:
Gloria Gaynor - Never Can Say Goodbye 1974
MFSB - TSOP 1973
Ultra High Frequency - We're On The Right Track 1973
Brass Construction - Movin' 1975
Harold Melvin & The Blue Notes - The Love I Lost 1973
Harold Melvin & The Blue Notes - Bad Luck 1975
The O'Jays - I Love Music 1975
Fatback Band - Spanish Hustle 1975
Don Downing - Dream World 1974
Temptations - Happy People 1974
Blackbyrds - Flying High 1975
Blackbyrds - Time Is Movin' 1975
Louis Ramirez - Salsa 1975
Deodato - Skyscrapers 1973
Salsoul Orchestra - Salsoul Hustle 1975
Salsoul Orchestra - Salsoul Rainbow 1975
First Choice - Armed & Extremely Dangerous 1973
Lyn Collins - Rock Me Again & Again X6 1974
Commodores - Superman 1974
etc............
Anyhow I guess I could say that disco music got more advanced in the late 70s with the more percussions eg "The Break" 1979 by Katmandu, electronica style eg "From Here To Eternity" 1977 by Giorgio Moroder etc......
Anyhow I guess I can say the real disco era was 1974-1980 because from 1974 onwards more and more disco records were getting released. Prior to 1974 there were more so soul and funk records being released but still quite a number of disco songs came out prior to 1974 which I mentioned above, well I call them disco anyway :D .
Anyhow that's my opinion on what is the "Real" disco era.
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Aussie Aussie Aussie!!! Oi Oi Oi!!!
Australia mate! The land of many great funkateers!
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