audioresearch
Member
- Joined
- Jul 15, 2023
- Messages
- 12
- Likes
- 9
I believe the distortion was high because the speakers you tested were old and most likely the spiders, and/or surrounds, and/or cones had deteriorated with age.
In the case of the surrounds, it is a known fact that the foam surrounds would often completely rot away with age and quite likely the ones in the speakers you tested were well on the way to failing totally. I believe that somewhere in the production run of the series V, the foam was changed to a different type of foam that would not rot.
Those problems would likely also affect the frequency response.
I have no idea how much the old foam surrounds contributed to the high distortion numbers, but at least the first two editions of the 901 (original 901 and series II 901) did not have the foam rot problem because they did not use foam, so perhaps they will have much better distortion numbers and maybe even frequency response also if you are able to test them one day.
I used to run 4 pairs of 901s which really took care of any limited output capabilities quite nicely at least until the day when all their drivers failed due to foam rot.
Nobody ever mentions one fantastic improvement made by the 901s: finally, at long last, a speaker system where blowing tweeters is not a problem when listening to loud music.
In the case of the surrounds, it is a known fact that the foam surrounds would often completely rot away with age and quite likely the ones in the speakers you tested were well on the way to failing totally. I believe that somewhere in the production run of the series V, the foam was changed to a different type of foam that would not rot.
Those problems would likely also affect the frequency response.
I have no idea how much the old foam surrounds contributed to the high distortion numbers, but at least the first two editions of the 901 (original 901 and series II 901) did not have the foam rot problem because they did not use foam, so perhaps they will have much better distortion numbers and maybe even frequency response also if you are able to test them one day.
I used to run 4 pairs of 901s which really took care of any limited output capabilities quite nicely at least until the day when all their drivers failed due to foam rot.
Nobody ever mentions one fantastic improvement made by the 901s: finally, at long last, a speaker system where blowing tweeters is not a problem when listening to loud music.