Component Identification

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Hello all.

I'm trying to fix a set of EV SP-1502 speakers. When they were given to me I was told the drivers were blown. When I hooked them up, one speaker did nothing and the other distorted badly and output seemed very erratic. I opened them up and directly connected the speakers individually to the power amp and found the speakers sounded fine, which led me to believe something is blown in the crossover.

The two components in the second picture are the ones i'm hard up to identify. I originally thought they were capacitors, but the labeling and placement makes me think they're resistors. Can anybody clarify for me? I know the big grey block is a 20watt 50ohm resistor, the copper coil is an inductor, and the big white doohickey is an 8ohm potentiometer for high frequency attenuation.
 

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So I think I found replacement parts for these, but I had a question.

I found 5uf 100v and 2.7uf 100v polyester film caps. I know having a higher voltage rating is ok, but will the lower capacitance of the second cap affect the crossover slope drastically?
 
The voltage rating is the same, 100V. As for 2.7uF vs 2.84 uF, given that the originals were 10% tolerance, if the 2.7's are close to nominal then they should be well within 10% of the original 2.84. If you can get 2.7's that are 5% or better you are golden!

So I think I found replacement parts for these, but I had a question.

I found 5uf 100v and 2.7uf 100v polyester film caps. I know having a higher voltage rating is ok, but will the lower capacitance of the second cap affect the crossover slope drastically?
 
Caps like that are usually fairly reliable, so I'd check the other components too if I were you... in particular the pot to see if it is intermittent. If it is, try to find a classic sealed wirewound model with double wiper, these are practically indestructible. I can imagine these speakers were dramatically overdriven for the crossover circuit to fail like that. Looking forward to know if your replacement caps solved the problem! :)
- Robert

PS: I do have a bunch of those 8 ohm wirewound pots if you need to replace 'em.
 
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aevek, mind if I post some unidentified electrical objects on here? I have an idea, actually. Why doesn't this topic get stickied so anyone who finds things they can't identify can post them all in one thread? It'd help keep the forum cleaner and give good visibility.
 
I don't mind Llamaboy. Sounds like a good idea to me.

And thanks Robert, I'll keep that in mind. However, I tested the pot and it seems fine. in fact, I pulled both caps and tested them, and they seemed fine as well. I'm kinda stumped, so i opted to just replace the whole shebang.

Only thing now is that the 5uF cap terminals aren't labeled. I really don't wanna put it in there backwards. Any ideas?
 

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A firing pin?

So, I ordered up Alltronics' Duke's Delight 5 lbs. Hardware Assortment. It'll save me a lot of time, having every basic screw I may ever need...despite the time I used to sort it all (still not done). Among all of the stuff; screws, bolts, nuts, cannon plug hardware kits, gold pins (!), etc, I found this:

Picture58.jpg


It looks like a firing pin. It feels like the world's cheapest firing pin, like from a pawnshop special or a zip gun. I've seen these things before, but now I actually have one and would like to know exactly what it is.

It can't be an actual firing pin, just can't.
 
So, I ordered up Alltronics' Duke's Delight 5 lbs. Hardware Assortment. It'll save me a lot of time, having every basic screw I may ever need...despite the time I used to sort it all (still not done). Among all of the stuff; screws, bolts, nuts, cannon plug hardware kits, gold pins (!), etc, I found this:

Picture58.jpg


It looks like a firing pin. It feels like the world's cheapest firing pin, like from a pawnshop special or a zip gun. I've seen these things before, but now I actually have one and would like to know exactly what it is.

It can't be an actual firing pin, just can't.

It's a rivet. You need a rivet tool to use it. You can get this tool at any hardware store.

David.
 
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