I just purchased a pair of 1979 EPI 100Ws for $5.....woot.
Their 8" drivers need to be re-foamed. I've done this before (Cerwin Vega) but:
Question 1:
How much is this likely to affect their performance? I understand that their original design depended on the mechanical characteristics of the drivers rather than an L/C crossover to separate the low and high frequencies. Clearly the foam I can buy on E-bay isn't from the manufacturer. But is it close enough?
Question 2:
What is a good way to check against the 'as new'? I've accumulated enough hardware to measure me a Bode plot. But I have no idea what it should have looked like from the factory. I have a darkly humorous anecdote about frequency response in modern vs antique test equipment, but I don't want to put it on the internet as it is slightly disrespectful of Nissan engineers.
Their 8" drivers need to be re-foamed. I've done this before (Cerwin Vega) but:
Question 1:
How much is this likely to affect their performance? I understand that their original design depended on the mechanical characteristics of the drivers rather than an L/C crossover to separate the low and high frequencies. Clearly the foam I can buy on E-bay isn't from the manufacturer. But is it close enough?
Question 2:
What is a good way to check against the 'as new'? I've accumulated enough hardware to measure me a Bode plot. But I have no idea what it should have looked like from the factory. I have a darkly humorous anecdote about frequency response in modern vs antique test equipment, but I don't want to put it on the internet as it is slightly disrespectful of Nissan engineers.
So how, exactly, does God know that She's NOT a brain in a vat? 
