Do I need new diaphrams for my 077 and LE85?

[David24x7]

If you just got some 077's and LE85's in the mail, what would you do to test the integrity of them?? I'm eager to put them thru their paces but don't want to rush into making any stupid mistakes.

They all make noise and I have the 077's connected to a crossover that I am using with my current speakers but they don't make much sound. Just thin and high and scratchy (and somewhat intermittant as one seems to have a loose terminal). Can I hook up directly to my amp (Sansui AU7500) or should I need to use a capacitor on the positive to protect them?

Unfortunately, I don't have any reference to compare them to but would appreciate your thoughts.

[1audiohack]

Oh you definitely need at least a capacitor to protect them from low frequency.

The loose terminal is likely the intermittent issue and be aware that turning the push terminal can turn the screw inside and break the riddon wire lead inside and ruin the diaghragm. 077's are fragile and easily damaged. If you are not familiar with them mechanically get some assistance before you rip into it.

Also these are pretty efficient and often out power other midrange speakers and tweeters and when just "hooked up" they can sound out of ballance and harsh, and they don't like to be crossed in below 7kHz with a 12dB slope being considered the minimum.

Someone would would have to measure their performance to really know if they are operating as they should.

Proceed with caution, those are nice drivers.

Good luck!
Barry.

[David24x7]

Thanks Barry. I have a 1UF capacitor that I was going to use for the 077's based on the Nelson Pass 4333 mod which uses a single 1UF cap in the circuit. I'll give them a try with that and see how it goes. Thanks for the warning about turning the terminal and possible resulting damage. I'm sure that I would have tried that without the warning.