I have a small African collection, less than 100 cds, lots of central African Soukous, Analog Africa and other collections. I purchased this in 2008, according to Amazon, although it doesn't seem that long ago.
I particularly like the women's voices on here. They are sort of reedy, like an oboe in its upper register. The melodies are sort of Arabic. Backing has a sort of accordion sound with various rhythm instruments. Sounds similar to Bi Kidude. Don't kmow much about it beyond what the liner notes had but really enjoy it. Not sure if samples are available but worth it. Just checked, allmusic has samples.
A little searching on the internet reveals that this is Taarab music from Tanzania and/or Zanzibar. These recordings were from 1969 to 1976. They sound pretty good though.