Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

In this Discussion

Who's Online (5)

Please review the site Rules, Terms of Service, and Privacy Policy at your convenience. Rules, TOS, Privacy
Get familiar with the reaction system: Introducing the Reaction System

If someone wanted to build a pretty decent 3-way...

...those 10" buyout subs from PE would do the trick. I spent a lot of time modeling them as subs, but thought I would do some modeling as traditional woofers anchoring a 3-way.

A pair in parallel, loaded in 50L and tuned to 30Hz yields some interesting results. I used 150W as my basis, since that yields 110db in the passband before baffle step loss and room reinforcement, so for purposes of demonstrating how capable these drivers are that is what I went with.

Here is the modeled response curve:



That is F3/6/10 of 30/27/23hz. That is not bad, not bad at all. Especially when you consider how little cone movement it takes to generate that SPL at 150W:



Zero worries about excursion under all but the weirdest of circumstances. Lets bump the modeled power up to, I don't know - 500W:





Here you see excursion limits are finally reached in the spectrum that *might* contain musical info. Again, unless you are addicted to 115db trance it is unlikely you will ever exceed Xmax. Even if a guy does, these things have a huge amount of Xmech - easily double the Xmax rating. This makes thermal burnout a possibility, these are only rated at 150 WRMS power handling. I would bet dollars to donuts it will handle that 150W from here to eternity and then some. On paper, the coil is listed as 50mm diameter, 4 layer winding, and 34mm long. That is a pretty large amount of copper. There is venting under the spider and under the dustcap, and although I would like to see a backplate vent I am confident the engineers considered and rejected that for good reasons. I believe it is safe to assume that for transients, 250W per driver will be very safe. 

This is all in less than 2 cubic feet, no EQ, no filters. 

Now for the bad news, and if there are any newbies reading this pay attention. This was done without any added series resistance. An reasoned assumption based on measured response and impedance could be made that crossing these over below 350Hz is best practice. Crossing that low passively will likely require extremely expensive low gauge coils and large caps to deal with the erratic response above 500Hz. This will, in all likelihood, take an ohm or two of series resistance to accomplish. That dicks my beautiful model pretty good :( 

But, by this point it probably makes sense to go at least hybrid active on a build like this - do a 2-way active (LPF on woofers, HPF on mid) and traditional between mid and tweeter. A beefy four channel amp would work for that, I wonder if I have one of those...

Playing with simulations is as good a way to spend my early morning as anything else. These are pretty phenomenal drivers. I have very little buyers remorse - in fact, I had zero until I saw PE clearanced the 12" for $125. Jerks. 

I have a signature.
joeybuttsdcibelsquamishdroc

Comments

  • Thanks for the writeup!
    Don, Donno, or "Hey you" all work for me, But never "Mr Johnson"
Sign In or Register to comment.