Sansui SP-2500X tweeter and midrange tests

[Pretzelogic]

Anyone know how to easily test the tweeters and midrange speakers on a pair of Sansui SP-2500X speakers? I recapped em over winter break, brake-oiled the woofers and they sound LIGHTYEARS better than they did before. Like really decent for some not-loved by the audio community speakers. Is there a sure fire way to test the tweeters and midranges using an multimeter?

 

[f0427ea]

Is there a way to test the tweeters and midranges using an multimeter?

Looks like the impedance is printed on back of the driver, make note of positive,negative wire colors,un-clip wires and measure in ohms x1 scale.
You will be measuring DCR , will be an ohm or two below what driver is. example: Mid-range speaker is 12 ohms, you should read around 10 ohms.

 

[Pretzelogic]

Looks like the impedance is printed on back of the driver, make note of positive,negative wire colors,un-clip wires and measure in ohms x1 scale.
You will be measuring DCR , will be an ohm or two below what driver is. example: Mid-range speaker is 12 ohms, you should read around 10 ohms.
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Do you know if they sell replacement tweeters of those sizes on place like parts express?

 

[f0427ea]

Do you know if they sell replacement tweeters of those sizes on place like parts express?

Best bet is to watch on the e-bay , get the same original Sansui tweeter , one will show up , most likely sooner than later.

 

[Pretzelogic]

These tweeters are Sansui T-138 12ohm 12watt tweeters. I need 4 of them or 4 comparable replacements.

 

[Eighthnote]

These tweeters are Sansui T-138 12ohm 12watt tweeters. I need 4 of them or 4 comparable replacements.

Did you ever find any T-138s? I have a box of them. I need to go through and test all of them. FOLLOWUP , Just finished going through a box of 14 Tweeters. Not good. Only three passed the Ohm and 9v battery test. 11 of them dead. Don't understand how something with no moving parts could go bad but I'm sure there's someone out there that understands these much better than I. Can these be rebuilt? I don't even see how to get them apart. They look like one solid piece of molded plastic with an imaginary DO NOT ENTER sign on them.

 

[A400]

9 V seems to high for tweeters, I’ve found 1.5 V to be plenty.

No moving parts? I’d guess these have a voice coil and diaphragm. I’d also guess that a break in the ‘tinsel lead’ which is actually an extension of the voice coil lead across the suspension is a common failure mode, based on older Sansui tweeters made by Coral.

More guessing, is that the magnet cover comes off, but probably you’d need to desolder the terminals first and who knows what else to make this disassembly go well.

 

[Eighthnote]

I'm going to take one of the non-responsive tweeters and experiment. Taking the terminals off looks fairly straight forward. After that is looks like a heat gun around the casing might get me inside where the working parts are located. There's got to be a way to bring these back to life. They're certainly not easy to find. People are even selling non-working T-138's online so there must be someone that has a way to rebuild them. Thanks for the reply. Cheers............