• 10-06-2010, 10:29 AM
    audio amateur
    5 Attachment(s)
    My most successful subwoofer build
    So as I was telling GM the other day, I've completed a subwoofer project which is actually the finishing of a semi finshed/working build I made 4 years back. At the time, it was my second subwoofer build and first ported build. I had left the exterior unfinished, and the sound was terrible (distorted even at low volume). It was a 3.5CF ported box using a cheap 12" Sony driver.
    I thought the problem was with the driver/enclosure mismatch but in fact the bracing partitions in the enclosure weren't letting enough air get from one chamber to the other. Eventually I gave the driver to a friend and left the box sit in the basement for 4 years.

    Recently i was contemplating using a decent driver in a new enclosure (sonotube) but then I figured I should give my dying enclosure another try. I went for another 12" driver (apparently a variation of the Lab12 Eminence driver) built to spec for a British company who also makes OEM products for other audio companies, such as REL. It models perfectly with this enclosure.

    Anyways, so I worked on the partitions (tough job given the limited room, did most of the cutting with the hand saw), placed the port a little differently which required adding another sheet of MDF on the side where the amp and port were - I decided not to mount the plate amp on the enclosure like I had before. Fortunately the previous 12" hole was just the right size.

    The colour paint I had planned to use was white, but I went with mat white as there was some in the basement already. I did buy some primer. 2 layers primer, 2 layers paint. My sander is crap so there are still some uneveness but it looked good enough so I just started painting it anyway. I am quite please with the outcome. Here are some pics, it sits behind the right speaker in my bedroom:D


    Attachment 7472
    You can see the plate amp which powers the sub. As Im using it with an HT receiver im thinking of going with a bridgeable NAD power amp instead or something similar


    Attachment 7473



    Attachment 7474



    Attachment 7475
    Yes that is my foot lol and don't ask me what the 6 by 9s are doing there


    Attachment 7476



    http://www.avforums.com/forums/attac...river-down.jpg
    Visually speaking, there's no denying the new driver is a completely different beast.

    There's a couple more to come...
  • 10-06-2010, 10:40 AM
    audio amateur
    5 Attachment(s)
    Attachment 7477



    Attachment 7478
    The 4" port...


    Attachment 7479
    Bottom pic. The small improvised feet using doorstops (I think that's what they are for...) + binding posts. The feet give enough clearance for the connections


    Attachment 7480



    Attachment 7481
    Only pic without flash just to give you an idea:)
  • 10-06-2010, 10:48 AM
    GMichael
    Wow. A white sub huh? I don’t think I’ve ever seen that before. It looks a little like a file cabinet. Nice!
    How does it sound? Are you going to get a BFD or another EQ of some kind? Any measurements yet?
  • 10-06-2010, 12:07 PM
    audio amateur
    Will post some more details tomorrow.

    I only took close ups because the rest of the system isnt ready for pics yet. Comments welcome
  • 10-07-2010, 12:12 PM
    Glen B
    Quote:

    Originally Posted by GMichael
    It looks a little like a file cabinet.

    My thoughts also. Well, as long as it sounds good. :D Is that the plate amp I see to the left in the pictures, hooked up to the sub ? If so, why not mount it in the sub ?
  • 10-07-2010, 12:48 PM
    audio amateur
    Sorry guys said I would write more ill try tomorrow:)
  • 10-08-2010, 12:15 AM
    audio amateur
    Quote:

    Originally Posted by GMichael
    It looks a little like a file cabinet. Nice!

    File cabinet eh? Why would say such a thing:(
    I was actually going to try and match it to the rest of the wood in my room, including the color scheme of my fronts, but then I was thinking of other colours. My rears are white so I was like white... why not? But yes I suppose a little strange for subwoofer. No more stranger that yours though! lol I can always paint it another color...


    Quote:

    Originally Posted by gmicheal
    How does it sound? Are you going to get a BFD or another EQ of some kind? Any measurements yet?

    No BFD yet, although Ill definitely consider it sometime... How have you gotten along with yours?
    So far I haven't done any 'serious' listening. Positioning is a little tough because there's not much room for it to move around where it is located. I just plonked it there without thinking about it too much. It's quite a beast and thus very hard to move around. It'd be even heavier if the amp was still on there... No doubt yours weighs a lot more still:yikes:

    I've adjusted the level so it matches the fronts when playing music and also with the SPL meter for overall matching with surround sources.
    I plumets to about 18Hz... If played loud enough the (non supportive) wall which sits right behind me vibrates pretty bad:D
    Actually is has useable response down to 16Hz after which is rolls off severly.
    Unfortunately at those frequencies you can hear some chuffing, but that's only noticeable because im playing test tones...

    It definitely does need some kind of EQ though afterwhich it should sound pretty good. Right now the nodes are exagerating some of the bass. But as I said I havent done much critical listening so far.
  • 10-08-2010, 12:21 AM
    audio amateur
    Quote:

    Originally Posted by Glen B
    My thoughts also. Well, as long as it sounds good. :D Is that the plate amp I see to the left in the pictures, hooked up to the sub ? If so, why not mount it in the sub ?

    Hey Glen, thanks. When I first built the sub i had the amp and port on the same side. Since Ive rebuilt it I decided the port wasnt well positioned and I decided I couldnt be bothered to make another hole for the amp (the new port position was where the amp was before, so i had to slap on a new sheet of MDF wood). It would have been difficult to find a new spot for the amp anyways because each side had some kind of obstruction (bracing, etc). It was easier to leave it off. Im thinking of replacing it with a simple power amp though, which would be more appropriate:)