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Jim Hickey
07-22-2006, 09:08 AM
Hi, I'm putting together some 4312A's and can't find any 3112C or D's anywhere. I can't use any other Xover can I? Thanks for your help, Jim.:blink:

Mr. Widget
07-22-2006, 09:48 AM
Welcome to the Lansing Heritage Forum. Even if you have never built a crossover before, this one shouldn't take you more than an hour at the kitchen table. If the schematic below looks totally alien to you one of us here can easily explain it to you.

You can purchase better than original caps, inductors, and L-pads from Parts Express or Madisound and not break the bank either.


Widget

Jim Hickey
07-26-2006, 08:24 PM
Thanks Wignet, I just got a pair of 3112B. If I add a 3uF to the 8uF cap and a .01 to the other 3uF, would that work? And if so , can I use film + foil? Thanks, Jim.

Mr. Widget
07-26-2006, 10:37 PM
I just got a pair of 3112B. If I add a 3uF to the 8uF cap and a .01 to the other 3uF, would that work?Not really and you still need L1... why use a pair of tired old cheapo caps and dirty cheapo L-pads, when you can easily build the networks from the ground up with new parts?


...can I use film + foil?Sure. They may change the tonal quality a bit, but they should work fine.


Widget

Jim Hickey
07-30-2006, 05:41 PM
OK,You've convinced me.Are 15 watt Lpads ok? What is an L1? What would be the best caps etc. to use? Anything else I need to know before I do this? It looks kind of simple,but alas ,tis me first time. Thanks.:blink:

Mr. Widget
07-30-2006, 06:00 PM
You could use 15 watt L-Pads... I would use 50 watters

Here are my recommended parts... not top drawer, but significantly better than stock and not much more costly than stock equivalent parts.

Widget


C1 Mid Cap:
http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=027-932&DID=7
C2 Bypass Cap:
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=027-700
C3 Tweeter Cap
http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=027-920&DID=7
C4 Bypass Cap:
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=027-700
L1 Mid Inductor:
http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=255-400&DID=7

Jim Hickey
08-06-2006, 05:58 PM
Thank You Widget. I purchased everything you suggested, put it together, and am now listening to an almost new pair of 4312A's.They sound great. I noticed they arent as punchy as my 4311Bs. I'm running them off an sx 1080. Thanks again, you've been a great help. Jim:applaud:

Mr. Widget
08-06-2006, 06:36 PM
I noticed they arent as punchy as my 4311Bs.Congratulations! I'm glad it worked out for you.

The 4311Bs have a pretty good sized bass bump... the 4312s are actually a significant improvement in my opinion as well as going a bit deeper. Give your ears a bit of time to get used to them.


Widget

Zilch
08-06-2006, 07:58 PM
May we see pics of your crossovers, please?

We're frequently advocating DIY crossover construction here, but many find the very concept intimidating.

Your pics might encourage others to give it a go.... :thmbsup:

Jim Hickey
08-07-2006, 01:08 PM
I'm sorry,they are already glued to the back of the front panel and that is glued shut. I kind of cheated a little. I used the network board from 4311B which basically has the same wiring, removed and added what was needed. I even had enough space for the L1 because the caps are smaller than the original ones.:o: