Realistic Optimus 1B

Re:"a Xover that would run 1 T/M as a Tweeter and the other as a Mid?" - you could try a small inductor (~ 0.2mH?) in series with the lower mid, and see how that sounds. If OK follow up with a small cap (~4.7uf?) in series with the top one. There may be balance issues however, I suspect the original used 2x M-Ts to match the efficiency of the woofer... or perhaps it was for power handling??

Just remembered these are '16' ohm drivers, so for an arbitrary 4KHz xover, 0.62mH & 2.7uF would be closer to the mark
 
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Re:"a Xover that would run 1 T/M as a Tweeter and the other as a Mid?" - you could try a small inductor (~ 0.2mH?) in series with the lower mid, and see how that sounds. If OK follow up with a small cap (~4.7uf?) in series with the top one. There may be balance issues however, I suspect the original used 2x M-Ts to match the efficiency of the woofer... or perhaps it was for power handling??

Just remembered these are '16' ohm drivers, so for an arbitrary 4KHz xover, 0.62mH & 2.7uF would be closer to the mark
HI, I am a newbe to vintage audio. I picked up a set of Optimus 1Bs at a thrift store. Woofers are great but the tweeters have been replaced with junk. I saw you replaved the mid=tweeters with a PS95 a couple years ago. How is that working today and do you have any suggestions if I do the same today? Alternatively, I will just search for 4 orig drivers. Thanks
 
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I upgraded their crossovers, and removed the tweeter level option. They sound better, but still mediocre at best. But the project was fun. :) .

That said, they can be enjoyable to listen to.

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PeteMcK, Going back to your initial post, how did you measure the TS parameters of the 2510A woofer? Manually, REW. DATS or ?
I'm using REW and so far am getting much higher Qts and Fs for the set I have. I wanted to use them in a 1.7 cu ft box, posibly ported but not sure yet as I need to do more analysis with WinISD. Using your values it would be a nice fit, but with my values not so good.
Thanks!
 
Hi 4R5, I use the LIMP module of ARTA, with a simple jig to make my measurements. With old speakers that have been unused for some time, the spider stiffens up and raises Fs & Qt. Unfortunately there's no magic potion that will decrease the stiffness of phenolic spiders, although it's work giving them a LF workout for several hours, which may make some difference. Cheers
 
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