I have put the links several times in the past.
In 2000 WTF ( in Portugal ) they used (for the first time) a 8% bigger ball and it was very noticeable how much it slowed down the shots (the ball speed decreased more than before through its trajectory).
Wimbledon changed to a slower ball in 1995 (after the 1994 Sampras-Ivanisevic final, where very few points had more than 4 strokes, even if other players in other rounds in that same tournament, for example Bruguera-Chang, played from the baseline and had longer rallies).
US OPEN slowed down its surface in 2001. They slowed down it again in 2003.
Wimbledon officials said that, even though they changed the grass type in 2001, the effect could not be that dramatic (many players complained about how slow and high bouncing Wimbledon's grass was in 2002 ) because they had been tweaking things since the middle of the 90s to make it possible to have longer points, but the changes had been gradually year by year, so it could not be that dramatic from 2001 to 2002 (officials said).
Little by little, all tournaments that had an indoor carpet, changed to a hard court during the end of the 90s and beginning of the 00s.
In the 80s and 90s, fast and low-bouncing indoor carpet tournaments were, at least, 1/3 of the season.
Already in 1994 and 1995 several players (Becker, Ivanisevic, Krajicek and more) complained about how tournaments officials had changed the conditions of many indoor tournaments, turning to a slower and higher bouncing carpet. For example, Paris-Bercy was called "the little Roland Garros" by several players in 1994 and 1995 because how slow it was (in their opinion) even if it was an indoor carpet tournament.
I have put the links of all this in the past (testimonies of tournaments officials and many tennis players).
It is not only the surfaces, but the ball type as well.
For example, in 2011 Roland Garros they used a lighter ball, and the change was dramatic, it was noticeably faster and way easier to hit winner shots, even if it was on clay.