amazings/plats crossover mod

I have a pile of parts,
have 1 set of low hr 30" ribbons
have 8 plat type woofers
have both types of crossovers, the amazing (30") type, (A) and the plat (3rd gen) type (B), not the mark4

if I do this will it work?????
want to take the A crossover and pull off the woofer parts.
and then use the woofer parts off of crossover B,
I think I drew it up right but not sure....
and the second thing I want to change the low/high crossover point to about 200hz, but I can go with the crossover from part B.
what, and how does one figure out what size cap to use, to get the crossover you want?


crossover A



crossover B




NEW.......?????

without looking up the xover point of the woofer, 450uf would make it around 80hz or so. the ribbons would have a huge gap to the woofer.

so I got one done, here are some pics....

So how does it sound with the hybrid crossover?

That is a lot of work - Those must be pain pills in that RX bottle back there! are those 30 inch Ribbons new ones? its going to be sounding real nice...

well the coil for the subs is suppose to have an ohm reading .4
1 is just that, the bank of subs is 3.9 as a set.....
the bad coil set reads 4.8
when I measure the bad coil it is 1.0 ohms
the other is right on at .4 ohms....
looks like I need to find a new set ...
but I will test them in the mean time....


also I found that the plats (ver3 60" ribbon) had the subs wired outa phase to the crossover and the print above....
hhhmmmm.... I wonder whats up with this...
oem bought new by me, never messed with this part before...
so the mystery as to the the phase grows....

Most coils when they go bad read either less than supposed to — like 0, or open — like ∞).

The reason for being wired out of phase is some components of the crossover invert the phase of the signal as it passes through---So inverting the wiring to the ribbons rectifies that inversion.

Most coils when they go bad read either less than supposed to — like 0, or open — like ∞).

That would depend on why they went bad; burned up (overload) would probably more likely created a short between windings (melted together), REDUCING resistance, whereas it would take a break in the wiring to INcrease resistance....

HUH? Nothing would increase resistance other than it going to infinity with a break.

HUH? Nothing would increase resistance other than it going to infinity with a break.

Sorry, mis-typed. Fixed now~

The reason for being wired out of phase is some components of the crossover invert the phase of the signal as it passes through---So inverting the wiring to the ribbons rectifies that inversion.

yes...

this set of plats was the end of the 3's, I wonder if the CO is diffrent, than the one above?
It don't matter really, just found it interesting is all.
so when it is said that the plats (60") are wired in phase to the ribbon/woofers, ya better look close because they may not be....
now to find new coils....

FYI, Silvers (in Rev. H) used the same iron core inductor (8.5mH, 0.4Ω, 616-00074-00)

okay....
I went and reread a few things.....

the ribbons on the silvers and plats are in phase to the CO, the woofers are out of phase to the CO...

the originals are, the ribbons out of phase to the CO, with the woofers in phase..... to the CO

me so stupid......

I did find new coils.....

http://www.erseaudio.com/Products/Super ... 1199706372

they are out of the 8.5mH but this will do....8.2mH raises the CO by 3Hz......

but one of the coils on the woofer part is bad, when I put a test tone of 1000Khz it plays loud and strong, while the left plays nothing, but a super faint tone, only when an ear is pressed to the woofer.....
so I need to order new caps also....
I did a few other checks and it comes back to a bad coil....
lets the highs go right on thru.....

also found out this....
when doing a phase test, take your preamp out of dolby phantom center channel mode...
it messes things up.....