[pelliott321]

Any help or suggestions would be greatly appreciated.
I lost one of my IIIa's mids yesterday. Its fixable, but a pain in the you know what. This is the second time since I rewired them last March and I need to figure out what I'm doing wrong. Both times its the same side (right). The 30ga wire is breaking right at the connection point on the panels frame well off the Mylar, so I am pretty sure it does not have to do vibration. The wires are glued down 3M77 and sealed with NF30. Its got to be a electronic thing. I do not drive them hard and if I was over driving the amp to clipping I would have blown the ribbon first since it is more delicate that the mids. I am not using fuses. IIIa's are in a hardwood frame and I am using AndyR's passive xover design, biamping the bass panels with a SS amp and the Mids and ribbons with glass.

So it goes.........

[SteveFord]

I'm sure that someone will be able to help you out some with this one.  Can you post a photo of the actual damaged part?
I still can't believe what you did to my old IIIa's, I never would have recognized them.

[pelliott321]

Thanks
sorry i did not take any photos.  You could barely see the break right at the solder terminal.
Any I rewired the mids yesterday and the first layer of NF 30 is curing for 24 hrs then a second coat goes on and let it cure for a few days before I listen.
I will post after it is back up 

[andyr]

Thanks
sorry i did not take any photos.  You could barely see the break right at the solder terminal.
Any I rewired the mids yesterday and the first layer of NF 30 is curing for 24 hrs then a second coat goes on and let it cure for a few days before I listen.
I will post after it is back up

Well done!

Just one point re. a second coat of NF30.  Does your other mid have 2 coats as well?  (Otherwise, you will probably get a level imbalance - the mid panel with 2 coats will be less loud.)

Regards,

Andy

[pelliott321]

Hi Andy
I see you found this place too.  Your generous knowledge will be a bright light here.
Any way I will be doing the other side as well along with two other panels I purchased for experimenting with (mainly or have spare ribbons handy).
Its tedious but I am using DAP to secure the the starting point. Then apply a bit of DAP at the other end and on the loop, let it set then stretch and apply, then back down to the bottom, apply a bit of DAP to mylar and the wire, let it set then stretch and apply, then back up and repeat.  Once all the runs are in place(two separate loops for the IIIa's) I paint a small are of NF30 in the middle of the run and make sure the wires are centered in the area between the magnets. You have time to move the wires a bit as the NF30 sets up. Once that sets then I can apply a coat for the whole length. Let that set for 24 hours the a second coat.  I thinks this is a pretty good method, but the proof will be in the playing, which will be this coming week end.   I just did not like the way the 3M super 77 set up and it look like to me that there was just too much mass.  Looking closely at the original (factory) It just looked like to me that they just used NF30.  I think Maggy's directions in the rebuild kits to use 3M Supper 77 is to make it go faster because it setup so quickly.  I maybe wrong but I will find out.     

[andyr]

Any way I will be doing the other side as well along with two other panels I purchased for experimenting with (mainly or have spare ribbons handy).

Its tedious but I am using DAP to secure the the starting point. Then apply a bit of DAP at the other end and on the loop, let it set then stretch and apply, then back down to the bottom, apply a bit of DAP to mylar and the wire, let it set then stretch and apply, then back up and repeat.  Once all the runs are in place(two separate loops for the IIIa's) I paint a small are of NF30 in the middle of the run and make sure the wires are centered in the area between the magnets. You have time to move the wires a bit as the NF30 sets up. Once that sets then I can apply a coat for the whole length. Let that set for 24 hours the a second coat.  I thinks this is a pretty good method, but the proof will be in the playing, which will be this coming week end.   I just did not like the way the 3M super 77 set up and it look like to me that there was just too much mass.  Looking closely at the original (factory) It just looked like to me that they just used NF30.  I think Maggy's directions in the rebuild kits to use 3M Supper 77 is to make it go faster because it setup so quickly.  I maybe wrong but I will find out. 
 

Aah, you shouldn't have a problem, then. 

When I relaid one of my IIIa mids, I decided to use 3M Super-90 as I understood it was a "better glue" than Super-77.  Well, it might well be "gluier" but it came out of the spraycan thicker than I thought it would.  The ectra weight on that mid panel reduced its output by a couple of dB - so I had to juggle my active XOs to compensate (easy to do, when active  ).

Good luck.

Andy

[pelliott321]

Yes I just was leery about adding a thick coat and dampen the mids too much.  we will see how it sounds   

[pelliott321]

well I rewired both mids, and I am back up and running.
Pics of xover box,insides,support, and methode to check mid polarity...9v battery, when stick goes up mylar attracted to magnets, I call it positive

[SteveFord]

Would you be good enough to do a write up on what you did regarding the crossovers and post that in the Maggie Mods section?  I'm pretty curious as to exactly what you did and how you like it.

[pelliott321]

After a few days of listening I think the rewiring both mids made a big difference.  I do admit the first time I rewired (last year) I was nervous and now that time went by and thinking about it, I came up with an very easy way (though more time consuming) the redo was easy and I did a much better job getting the wires straight better aligned between the magnets.  I have played them quite loud (better than 100dbs on the RAT SHACK meter with out any problems.

the xover mod is from MUG found at
http://www.integracoustics.com/MUG/MUG/tweaks/AndyR/
AndyR was a big help to me, he is generous, and patient.