• 08-28-2005, 09:39 PM
    ronning
    "Fantasy" DIY Tower Speakers
    Hello all.

    The short: Side-firing woofers: good or bad?

    The long:

    I've been exposed to loudspeakers for a long time and despite much reading loudspeaker how-to books and playing around, I still remain a novice at this. But it's still fun.. ;-)

    I'm a product designer by trade and thought for a fun project I'd try to design some GOOD LOOKING, INNOVATIVE, but not necessarilly the greatest-sounding speakers in the world (I still haven't figured out crossovers). Sacrilege, I know. But bear with me.

    If I can sell my ideas I may be able to get some engineers on my side to help with the gritty stuff.

    So here's my concept: 3-way system. dome tweeter, dual mid-basses (5-6"), side-firing woofer (10-12"). Floor standing. This configuration (a la Infinity prelue, Genesys 6.1, etc) works well for cosmetic fun. It will be a PASSIVE system. Are there any disadvantages to a side-firing woofer? What about dual in-phase opposing woofers? (like the Genesys)

    Thoughts, suggestions, wild ideas welcome!
  • 08-29-2005, 03:23 AM
    kexodusc
    Nothing wrong with side firing woofers, provided they are "subwoofers". I'd want to keep their top end response below 90 Hz. 80 or lower. It'd be best to use steep filters too, 18 dB or, better.

    I'm building something similar right now. Just an MTM with a "subwoofer" compartment underneath. All integrated into one box.

    You'll have to better explain the dual in phase opposing woofers. Not sure I follow. Though, I'm thinking box volume could get tricky if you start adding a 2nd 10" or 12" woofer in any alignment.
  • 08-29-2005, 05:57 AM
    squeegy200
    I think that was the premise behind the classic AR-9s by Acoustic Research back in the early 80s.

    The one that comes to mind is the Gallo Nucleus Reference 3 speakers which incorporate your design feature.

    See
    http://www.roundsound.com/ref3.html
  • 08-29-2005, 07:31 AM
    JohnMichael
    Quote:

    Originally Posted by squeegy200
    I think that was the premise behind the classic AR-9s by Acoustic Research back in the early 80s.

    The one that comes to mind is the Gallo Nucleus Reference 3 speakers which incorporate your design feature.

    See
    http://www.roundsound.com/ref3.html

    The AR 9's were an incredible example of side firing woofers. In the days when I sold audio we carried the AR 9's and powered them with Phase Linear. The bass was incredible in those days and we always had them playing when the Bose rep stopped by for a visit. We would remind him that this is what accurate bass sounds like. Now let's play it through the 901's and of course he would have a story as to how the Bose were really more accurate. I regret not buying a pair of AR 9's and I am pleased to say I did not buy the 901's. I did not buy the spin about the 901's being more accurate either.
  • 08-29-2005, 10:01 AM
    ronning
    Yep, exactly the same for me. A MTM box "coupled" to a "sub" box, although it will be a passive woofer with a target tuning frequency of 30hz. The MTM I was planning to be an acoustic suspension for tighter mid-bass.

    The dual-woofer concept would be 2 horizontally-opposed side-firing woofers, ie one on the left one on the right. They would fire *in-phase*, to prevent bass cancellation. With the potential for High SPL, it seems this might get messy and the cabinet might have to be *huge*, not to mention it might kill my 110/ch yammie amp.

    Any thoughts?

    To be realistic, I'm not starting to lean towards a front-firing 10" or 12". It's just a matter of getting the aesthetic proportions right so it doesn't look like a monolith in my living room... ;-)

    Thanks everybody for your thoughts!

    p.s. Anybody know where i can find a picture of the old AR9's?
  • 08-29-2005, 10:42 AM
    ronning
    Also...

    I can't seem to find any nice, quality alumium dome woofers bigger than 7"

    Anybody know where I can find some?

    I like the aluminum because A) it looks sweet and B) sounds really good

    If you can suggest something else that meets those 2 points, let me know.

    Thanks!

    p.s. Not looking to spend more than $100/woofer (10" or 12")
  • 08-29-2005, 01:35 PM
    kexodusc
    Aluminum "dome" woofers? No...but for quality Aluminum cones, look no further than Seas:
    http://www.madisound.com/cgi-bin/ind...28876&pid=1041
    They have others, this is just one.
  • 08-29-2005, 02:00 PM
    squeegy200
    Quote:

    Originally Posted by JohnMichael
    The AR 9's were an incredible example of side firing woofers. In the days when I sold audio we carried the AR 9's and powered them with Phase Linear. The bass was incredible in those days and we always had them playing when the Bose rep stopped by for a visit. We would remind him that this is what accurate bass sounds like. Now let's play it through the 901's and of course he would have a story as to how the Bose were really more accurate. I regret not buying a pair of AR 9's and I am pleased to say I did not buy the 901's. I did not buy the spin about the 901's being more accurate either.

    I sold stereo gear when I was in college. Same experience here. People came in to hear the 901s and gloated over it as if it were some revelation. I thought they sounded a lot like a loud midrange driver in a box pointing backwards.

    I did a search for the classic AR 9s and found one on eBay.
    These are the speakers I remember.
    http://cgi.ebay.com/Teledyne-Acousti...ayphotohosting
  • 08-29-2005, 03:09 PM
    ronning
    Quote:

    Originally Posted by kexodusc
    Aluminum "dome" woofers? No...but for quality Aluminum cones, look no further than Seas:
    http://www.madisound.com/cgi-bin/ind...28876&pid=1041
    They have others, this is just one.

    Ha, yes... a quick slip of the tong.. er... fingers.

    Thanks for the link. I saw these elsewhere although here they have a 10" as well (although it's $110). Any other ideas? (maybe i can just spraypaint a normal woofer silver/white... ;-)
  • 08-29-2005, 03:11 PM
    kexodusc
    Hi-Vi Research has a some aluminum as well...you're best bet would be to visit Madisound or Parts Express' website and search.
    Aluminum is a popular material, though for that size, it's probably not as common as other materials.
  • 08-29-2005, 03:42 PM
    Geoffcin
    Quote:

    Originally Posted by ronning
    Hello all.

    The short: Side-firing woofers: good or bad?

    The long:

    I've been exposed to loudspeakers for a long time and despite much reading loudspeaker how-to books and playing around, I still remain a novice at this. But it's still fun.. ;-)

    I'm a product designer by trade and thought for a fun project I'd try to design some GOOD LOOKING, INNOVATIVE, but not necessarilly the greatest-sounding speakers in the world (I still haven't figured out crossovers). Sacrilege, I know. But bear with me.

    If I can sell my ideas I may be able to get some engineers on my side to help with the gritty stuff.

    So here's my concept: 3-way system. dome tweeter, dual mid-basses (5-6"), side-firing woofer (10-12"). Floor standing. This configuration (a la Infinity prelue, Genesys 6.1, etc) works well for cosmetic fun. It will be a PASSIVE system. Are there any disadvantages to a side-firing woofer? What about dual in-phase opposing woofers? (like the Genesys)

    Thoughts, suggestions, wild ideas welcome!

    I've owned two speakers with side firing woofers, the Gallo Reference 3, and the Cambridge Soundworks T500. Both were well designed and great speakers in their respective catagories. I would recommend a room larger than 12' across though, as you can develop some unusual room nodes with a side firing woofer, and narrow room.

    Your concept sounds fine, but it's not something that I would want to try for a first project. Speaker building, like anything else, is best learned from the ground up. Your project is pretty advanced for a first time project.
  • 08-29-2005, 04:17 PM
    ronning
    I agree, it's a bit complicated. But I plan on having these as speakers to experiment with. Also, I hope to be getting some qualified (loudspeaker) engineers i know to help me out.

    I think i've settled on the SEAS drivers, using the 10" woofer, 4" or 5" mid, and the aluminum dome tweeter. The last I've heard is good, although I'm a bit tentative about a metal dome tweeter. Anyway, it would "acoustically" match the others, at least in theory.

    The woofer is rated with an 87dB sensitivity, the 5" drivers are 86dB, and the tweeter at 92dB. Obviously I can use crossover & lpads to adjust, but would the MTM layout (having the mids blend better with the tweeter) overshadow the woofer output? Any thoughts on this are appreciated.

    Thanks!
  • 08-30-2005, 12:16 PM
    JohnMichael
    Quote:

    Originally Posted by squeegy200
    I sold stereo gear when I was in college. Same experience here. People came in to hear the 901s and gloated over it as if it were some revelation. I thought they sounded a lot like a loud midrange driver in a box pointing backwards.

    I did a search for the classic AR 9s and found one on eBay.
    These are the speakers I remember.
    http://cgi.ebay.com/Teledyne-Acousti...ayphotohosting

    I suggested to the rep that we place them on subwoofers and place a ribbon tweeter on top and then we might have something. Richard Sequerra was doing something similar at the time with his Met 7's and subwoofers and ribbons. I think some folks were using Janis woofers with stacked Quads and a ribbon tweeter at about the same time. I never got around to trying it though. Yes it was good to see the AR9's again. There was a time when I thought if I heard Pat Benetar sing Hell is for Children one more time over Bose 901's I might lose my love for music.
  • 09-02-2005, 09:31 AM
    46minaudio
    [QUOTE=kexodusc]
    I'm building something similar right now. Just an MTM with a "subwoofer" compartment underneath. All integrated into one box.QUOTE]
    So Kex u gonna let us know.Ported or sealed,What drivers.Are they clones or your own invention?Pics I want pics.
  • 09-21-2005, 04:53 AM
    Timn8ter
    Quote:

    Originally Posted by ronning
    The dual-woofer concept would be 2 horizontally-opposed side-firing woofers, ie one on the left one on the right. They would fire *in-phase*, to prevent bass cancellation. With the potential for High SPL, it seems this might get messy and the cabinet might have to be *huge*, not to mention it might kill my 110/ch yammie amp.

    Any thoughts?

    To be realistic, I'm not starting to lean towards a front-firing 10" or 12". It's just a matter of getting the aesthetic proportions right so it doesn't look like a monolith in my living room... ;-)

    A bipole bass box will give you the following:
    1. Increased acoustical output from increased displacement.
    2. Increased sensitivity.
    3. When wired in-phase the effect of the mechanical motion of the drivers on the cabinet will be nullified.
    4. Depending on the cabinet design you may also experience greater cone control due to air suspension effects inside the cabinet.
    Disadvantages are:
    1. Limited placement options
    2. Cost
    3. Size
    4. Possibly power consumption but that can depend on which drivers you choose and what SPL you're hoping for. You may want to consider going active for the bass box.