HBO 1975 promo music

[filmwritr3]

Hey guys,
Any info on the music in this HBO promo? This was also used for another pay cable movie service, the now-defunct Home Theater Network.

There are also some variations to this theme, as demonstrated in these HTN videos.

and

Any info on this is much appreciated. Thanks!

[Sanson]

I am in search of this song too. There is another video with the same track: