Spica TC-50 crossover refresh

I have a pair of what I believe are the original version Spica TC-50 speakers. They are a matched pair with matching crossover codes. I have read that the codes indicate specifics of the exact measurements of the parts (i.e. they were matched tighter than the tolerance of the parts). I don't think they sound as coherent as they did 30 years ago when I was running them regularly, perhaps the electrolytics have drifted. I suppose I should measure them.

Here's my question: would it be possible to trim the capacitor values using just a decent quality condenser mic (I have AKG perception 220), a computer and audio interface? I remember that the speakers were designed to be particularly flat in frequency and phase response at the crossover region (somewhere around 1k or 2k if I remember right). In other words, can I measure the crossover accuracy without buying more equipment? (No problem acquiring / compiling open source software as needed.) Thanks for any help.
 
Did it occur to you that the drive units themselves may have deteriorated in 40y time? Swapping caps won’t fix that.

On the mike, yes of course you can use it for loudspeaker measurements. But it is a bit rudimentary, the AKG has nonlinear behavior of itself and I’m not sure how it behaves in a free sound field.

Just try it and get acquainted with acoustic loudspeaker measurements. A decent microphone can be had for under $100. So you have upgrade options too, assuming you have budget for new caps.
 
Another variable to consider concurrently with those already noted is that the ears have aged 30 years as well. And consider whether the room’s properties, speaker placement etc. play into the equation. My .02.
Upside - Measuring will be a good project and a chance for learning.
 
I suppose the surrounds and other moving parts may have stiffened up. I've never seen anything regarding how much of a problem aging parts in a speaker are, other than foam surrounds, which is not applicable here. My ears are definitely not what they used to be.
 
I thought this brand was exclusive to portable AM radios that were very famous here, in Argentina !!. Many football fans attended the stadiums equipped with their "Spicas", and followed the game's events by tuning into the broadcasts of their favorite announcer...
Sorry OT
 

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