Terminal Cups: Dual vs Single

Discussion in 'Archived Threads 2001-2004' started by Robin Smith, May 13, 2002.

  1. Robin Smith

    Robin Smith Stunt Coordinator

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    In the ever-complicated quest for me to complete my first DIY sonosub, I have run into yet another problem.
    I purchased a dual terminal cup (http://www.partsexpress.com/pe/showd..._ID=5675&DID=7 but since I am using a 15" drive in 20" sonotube, I fear I don't have enough room for all of it to fit on the bottom end cap. To accomodate everything, the driver would have to be be ~1.5 inches from the edge of the inner end cap, there would be roughly 1" between the driver cutout and the terminal cup cutout, and then the terminal cup would be ~1" from the other edge of the innner end cap.
    These distances seem too small to me to be strong. Thus I am thinking of switching to a single terminal pair as the footprint/cutout should be way smaller. All I give up is the future ability to bi-amp, right? If so, I don't care too much as I am not likely to want do this any time soon (the hope is it is enough without needing dual amping). I am driving it with a PE 250W plate amp.
    So...
    Would this:
    http://www.partsexpress.com/pe/showd..._ID=5673&DID=7
    suffice, or should I spring the extra cash for:
    http://www.partsexpress.com/pe/showd..._ID=5684&DID=7?
    The first one has the smallest footprint, which would be best for my space limited end cap, but it is no use to me if it is crappy.
    Also, does the second one accept banana plugs, or just bare wire? Its hard to grasp the scale of it to know whether the holes are big enough. I want to use bananas if I can.
    With the first one I would be able to space all the cutouts two inches apart/from the edge which gives me more confidence.
    Finally, how would the single set of speaker binding posts change how I wire the dual voice coils (if it all)?
    Thanks in advance
    Robin Smith
     
  2. Brian Fellmeth

    Brian Fellmeth Supporting Actor

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    Can you create some extra space by making the driver cutout a little off center ? You could also recover some stregnth by glueing a plate of MDF over most of the hole (leaving room or wires) on the inside surface of the endcap.
     
  3. jeff lam

    jeff lam Screenwriter

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  4. Eduardo

    Eduardo Agent

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    I am also in the same boat. I am using the 12" Shiva and my tube is only 18" internally. I wase considering post but was unsure of the pros and cons versus posts with plates.

    Jeff how did you seal the posts and how thick was your endcaps. My endcaps total 1 3/4".
     
  5. jeff lam

    jeff lam Screenwriter

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    Those posts are very tight if you do it properly. I used a dab of wood glue on the teeth of the post and softly hammered the posts in till they were flush. You can also seal it from the other end with glue if you wish.

    My overall endcap was 2.25" (tripple layered 3/4" MDF). I had to bore out a 3/4" hole about 1" or so deep on the other (back) end to fasten the post in with the hex nut, the post's are 1.5" long I think and will fasten up to 1" so for your 1 3/4" thick baffle you will need to bore out about 1/2" or so.

    Madisound may have a longer post if you don't want to bore out the backside.
     
  6. Robin Smith

    Robin Smith Stunt Coordinator

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    I already have the driver cutout planned to be off centre and still there is not enough room!

    Jeff, those posts look like just the ticket! Thanks for the tip. I would prefer to centre the driver if possible and with those posts I am pretty sure I can do it. I'll be placing my order today!

    Thanks for all the input...

    Robin Smith
     
  7. Brian Bunge

    Brian Bunge Producer

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    Robin,

    I also used those posts on my dual SV12 subwoofers. All you do is is drill a 1/4" hole for the post to go through. When the knurled part comes in contact with the MDF you'll need to use a rubber mallet (or hammer with some protection on the post) to drive them all the way in. This creates an air tight seal and the posts won't move at all.

    Brian
     
  8. Eduardo

    Eduardo Agent

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    Brian - Do you have any pictures. I am pretty sure I know what you are talking about but I don't want to mess up.
     
  9. Brian Bunge

    Brian Bunge Producer

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    I don't think I have any pictures of the binding posts, but I can take a close up picture of one tonight and email it to you.

    Brian
     

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