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MG II crossover info needed

50.46.212.65

Hello! I recently purchased some MG II's for less than $100, and all that needs work are the crossovers. The stock parts were removed by another owner, and they made external boxes for aftermarket inductors and caps (one of each per speaker). I'm not finding any values on them, but the inductors are the ribbon foil type. Unfortunately, the right speaker has a torn inductor about 2" from the soldered joint. I'm assuming it's ruined? It looks like two replacement foil inductors will run me around $120 if I go for 2mH size. They seem hard to find and expensive! I like that I have the setup to go custom, but I just want to get these running first.
First of all, what are the stock values for the inductor and cap? I called Magnepan, but they said they had to dig for the specs, and they never called back. I've scoured the net, but I seem to only find mg IIa schematics. It seems like I could go cheap for now and put them in the external boxes.
Second question, if I go for the foil inductors, what are the recommended specs for upgraded inductors and caps? I'm not "gunning" them for now, I just want to enjoy them for a bit. Simple is good.
These will be for rear surrounds, and my 2.7QR's are the fronts :)
Thanks!

-Hamid

Follow Ups:

RE: MG II crossover info needed - neolith 17:54:40 01/27/17 (0)
First, there are three versions of the MGII -a, b and c. The MGIIa had a 3rd order LP (bass) and 2nd order HP (treble). That would mean 3 inductors and two caps. So you probably have the IIb or IIc - no matter both have the same crossover. The cap for the HP is 20 mfd and this may be two 10 mfd caps wired in parallel. The inductor for the bass is 2.2 mH.

As RickeyM says the inductor is repairable. As he describes just scrape off the coating at the tip of the coil with emery or fine sandpaper and solder the connection.

If your panels are intact, you got a great deal. The IIb excellent bass but the treble does roll off above 16 kHz. Good luck!

I married the perfect woman. The downside is everything that goes wrong is my fault.
Notsofastthere... - RickeyM 16:47:26 01/27/17 (3)
The torn inductor isn't ruined. In fact if you bypassed the torn section and connected the crossover wire there you'd be hard pressed to notice the difference in sound between the two speakers. IMO, with the length of foil in those inductors, two inches less shouldn't make an audible diff. If you want to be persnickety about it, shorten the length of the other inductor two inches as well.
- RE: Notsofastthere... - Mirewesh30 21:34:29 01/27/17 (2)
  Thanks guys! Yeah, there is only one capacitor and one inductor per speaker. I still haven't found the spec of the foil inductors yet. I will clean the foil and try hooking it back up! I'm not great at electrical stuff, but I'm learning. I think I'll be trying my hand in soldering the silver tweeter wires to the posts on the speakers, then running a small length of copper wire to the crossover boxes. I got the speakers with the boxes screwed into the back of the speaker, with the driver wires sticking into them.
  Is that glue just normal silicon glue I can find at a hardware store? Should I just coat the electrical connections after soldering with the stuff to insulate? Is it to prevent anything touching them?
  
  I tried one speaker last night. Not quite the shimmer as my 2.7's, but I probably need the other one running to get a better idea how they sound. There are two small sections where I'll use some Dap to eliminate a small gap. They were recently rewired and it looks pretty good. My 2.7's have a buzz in the lower registers, so I'm thinking the MG II's will help me prepare for tackling that project. It might save me $700 from sending them to Magnepan!
  - RE: Notsofastthere... - Satie 22:06:40 01/27/17 (1)
    As said above, the inductors are an easy fix. The delamination should not be a big challenge either. Just don't use too much glue and try to prepare well and keep things as clean as you can while you work.
    
    I don't really understand what the issue is with having the crossover boxes remain as they are if they are working and the speaker vibrations are not coloring sound from them. You can wedge in wood supports between the floor and the boxes to dampen the vibrations. Styrofoam blocks would work too. .
    - RE: Notsofastthere... - Mirewesh30 22:11:00 01/27/17 (0)
      Right! I'll keep them in the system, as I don't think they'll fit in the back of the speaker anyway. I just wasn't sure if I should try to go back to stock cheaper equipment if my current aftermarket stuff is shot. Either way, I'll use the boxes as they look pretty nice. Thanks!
      
      -Hamid
RE: MG II crossover info needed - Mirewesh30 01:25:05 01/27/17 (0)
I should add that I just found the specs on the caps I have. They're Kimber Kaps, 10uF 200v. Not sure what inductors I have, or if I can find a less expensive substitute for now.

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