Im looking for a 3.5 inch midrange driver: Original 902-4144. Substitute 902-2652 for one of my speakers it is reading open according to my DMM. I live in Western Australia and the cheapest one I could find was $90 from the USA including postage so Im wondering if anyone here knows if there is another cheaper driver with the same frequency response I could use instead?
Excellent idea! Ive got to work out how to get the driver out of the tube its in first! Ive already broken a scalpel trying to cut through the hard black glue holding the driver to the tube underneath. It looks like the previous owner has refoamed these and botched one because the foam surround is a bit out of shape, Im hoping its not a worn through voice coil but I wont know until I can get the bloody thing apart! lol
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Interesting, the wires look as if these are on the outer side of the cone. Try to dissolve the glue closer to the vc former and then use dmm. If it shows dcr, then the fault is on either side or both. First get to the wire in greater circle area and do the dmm test from driver terminal to there. Could be the plastic box won't have to come off.
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I disolved some glue with acetone next to the voice coil but I couldnt see any break in the wires. The wires come out of the voice coil across the top of the cone to the red Xs then dive under the cone. There is continuity on each individual wire at the end of the tube up to the red Xs but no continuity across the red Xs! So it looks like its broken inside the voice coil. I didnt do a DMM test from the voice coil edge to the driver terminals because I can see they are intact.
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Yes I suspected it was a worn out voice coil when I seen the refoam was off center. When I moved the coil in and out by pressing on the dust cap I could feel it scraping. I will scrape the enamel off right next to the voice coil and check it with a DMM tomorrow just to be sure. Its getting late here so Ill get back on how it went?
I finally got around to scaping the enamel off right up next to the voice coil but no luck there, I got continuity back to the terminals at the back, both sides. Now if I could just find a driver with the same size and specs instead of paying through the nose for a refoamed driver? Im going to need two because I dont trust the other one because that was refoamed by the previous owner as well!
I think you will be pushing to find a cheap alternative PP cone at about 90dB. Looking at the crossover, the mid is done via a simple 1st order electrical xo so would need a very well behaved driver to drop in plus the roll off at each end needs to be the same.
I found this new replacement but is more expensive than you have mentioned but it's not a repaired driver.
MW Audio MM-2652: Infinity Copy Midrange for Inf part # 902-2652
You could always send the drivers to Speakerbits for repair but would be more than the above I imagine.
With the xo and driver specs in the link above, someone might have some ideas. Supplying some driver dimensions could help.
It all comes down to how much you like the Infinity speaker (I was fond of their early speakers).
I found this new replacement but is more expensive than you have mentioned but it's not a repaired driver.
MW Audio MM-2652: Infinity Copy Midrange for Inf part # 902-2652
You could always send the drivers to Speakerbits for repair but would be more than the above I imagine.
With the xo and driver specs in the link above, someone might have some ideas. Supplying some driver dimensions could help.
It all comes down to how much you like the Infinity speaker (I was fond of their early speakers).
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I restored an Infinity SM150 a few years ago and I liked the sound of that but Im not so keen on the RS-5000, they have a muddy, booming bass but that might be the electros in the crossovers? Anyway these infinitys are not worth spending that kind of money on because I have to get two midrange drivers plus the postage. Im not fussed about getting PP cones, just drivers with the right frequencies and a 3 inch diameter. Now I know why they only cost me $10 for the pair. lol I could buy another set of RS-5000s for the price of those replacement drivers and keep this one for spares!
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