Hi there, I have an opportunity to get a pair of 15" speakers made in 70's. What I wonder about is - do speakers change their quality with the age or not? Can I rely that they'll be up to specs of the time they were made? Thanks for help!
I don't know what type of magnet the Tannoy's have, but something to keep in mind is that AlNiCo magnets get weaker with age. Also, they can loose much of their magnetism if they are dropped or other impact occurs. Having them re-magnetised can be tricky, depending on their design. Most of the vintage AlNiCo drivers I've had are fine, but I've had a couple that had the magnet much weaker than it should be.
Perfect; they have a pretty flat impedance curve that stays above 5ohms most of the time; so a tube amp is perfect for them. Which amp did you have in mind?
There is no way that the speakers will be as good as new. All materials change with time and any change takes the speaker further away from its intent.