Announcement

Collapse
No announcement yet.

midrange enclosure

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Dave Bullet
    replied
    One thing to bear in mind with oversized sealed enclosures is the high pass effect / rolloff at lower frequencies - essentially your F3 shifts up. That's what I found and had to compensate in the crossover since the rolloff began around 300Hz with a box Qtc below 0.5. I was trying to create as much distance as possible to the back wall to allow varying densities of stuffing to absorb backwave. I probably should have also targetted a transient perfect Qtc 0.5 enclosure size.

    Another good thing to do is have a removable back on your test box. That way you can effectively run it open back - placed where you normally would and see if there is any acoustic cancellation to take into account in your XO plus how it sounds to you.

    Leave a comment:


  • fpitas
    replied
    I've seen guys use a sturdy large-diameter pipe to the back of the cabinet, and try different amounts of stuffing, and closing or not closing the back of the pipe. That way you can experiment.

    Leave a comment:


  • analogkid442
    replied
    OK, Thanks for the replies. I will probably go with a closed box that is stuffed. I suppose I will have to experiment and see what I like, I will be crossing over around the 300-500 hz range.

    Leave a comment:


  • Billet
    replied
    I have had good success with the Fourjay PH8-1 Protective Backbox with about 75% poly fill. It works very well if you have room for it.

    Leave a comment:


  • AEIOU
    replied
    Originally posted by analogkid442 View Post

    I think you misunderstood what I am asking. I am trying to decide between several midrange drivers I have but I guess that doesnt have anything to do with my question.

    Better put, what enclosure sounds better for a midrange driver? For instance, I have heard that open tubes sound less boxy.
    James Moriyasu did a nice study on midrange enclosure and a writeup in audioXpress magazine. Basically he concluded, the bigger the better. Yes, you do need to add stuffing, how much though is usually empirical.

    Leave a comment:


  • rpb
    replied
    I probably would design one with one to three inches of dense fiberglass covering 80% of the walls in a random fashion. Any sound that makes it past that shouldn't be very audible, whether it's a sealed box, or open in the back. So if I left the back open, the sound would still be passing through fiberglass, and maybe foam too. I don't want any reflections to bounce back against the back side of the cone.

    Leave a comment:


  • fpitas
    replied
    Originally posted by analogkid442 View Post

    I think you misunderstood what I am asking. I am trying to decide between several midrange drivers I have but I guess that doesnt have anything to do with my question.

    Better put, what enclosure sounds better for a midrange driver? For instance, I have heard that open tubes sound less boxy.
    That doesn't have to be true. A sufficiently sturdy, non-resonant back chamber filled with absorber won't sound boxy. But as we have been discussing, it's a matter of preference if you want an open pipe, or not.

    Leave a comment:


  • bradley.s
    replied
    Ha ha. That's the perfect first question: do you prefer plain vanilla or chocolate? Then, where are you going to eat your favorite ice cream, in a car, in a home theater, in fetal position crying over lost loves?

    Leave a comment:


  • fpitas
    replied
    Originally posted by bradley.s View Post

    That means the answer to the OP's question is: it depends. Then the OP needs to explain how he intends to use the speaker.
    True! But he may need to try with and without a back panel on his midrange enclosure. We can't tell him if he prefers vanilla or chocolate ;)

    Leave a comment:


  • bradley.s
    replied
    Originally posted by fpitas View Post

    That, and some people like the sound of the back wave reflecting off the walls etc. Some don't want that. It's all down to what you prefer.
    That means the answer to the OP's question is: it depends. Then the OP needs to explain how he intends to use the speaker.

    Leave a comment:


  • fpitas
    replied
    Originally posted by a4eaudio View Post
    I think Bill's point is that there is no specific enclosure that sounds better for all mid-range drivers, it depends on the Thiel-Small parameters and box modeling. Some people love open-back mids but that is not a blanket statement for all mid-range drivers - they would then want to identify drivers that will actually perform well under those circumstances.
    That, and some people like the sound of the back wave reflecting off the walls etc. Some don't want that. It's all down to what you prefer.

    Leave a comment:


  • a4eaudio
    replied
    I think Bill's point is that there is no specific enclosure that sounds better for all mid-range drivers, it depends on the Thiel-Small parameters and box modeling. Some people love open-back mids but that is not a blanket statement for all mid-range drivers - they would then want to identify drivers that will actually perform well under those circumstances.

    Leave a comment:


  • fpitas
    replied
    I'll point out that with a long tube filled with a good absorber, it doesn't matter if you close the back. If you want the sound of some back wave escaping, you will have to moderate the stuffing, although without some you'll get a pipe resonance.

    Leave a comment:


  • bradley.s
    replied
    Do. Or do not. There is no try.

    Leave a comment:


  • analogkid442
    replied
    Originally posted by billfitzmaurice View Post
    You model midrange drivers the same as with woofers. Between the modeling for the region near Fs and the data sheet SPL charts for above that there's little need for testing, especially if the charts show off-axis.
    I think you misunderstood what I am asking. I am trying to decide between several midrange drivers I have but I guess that doesnt have anything to do with my question.

    Better put, what enclosure sounds better for a midrange driver? For instance, I have heard that open tubes sound less boxy.

    Leave a comment:

Working...
X