Help with a tapped horn.

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
sorry, bp102 doesn't model well AT ALL as a TH. and in a cabinet tda audio style, it's a definite no go. I actually can't model a FLH with a bp102 where xmax isn't exceeded above 50 watts... makes me wonder why it's such a big hit in BFM land? If anyone else knows of a good bp102 cabinet, let me know. I have some VERY low hour bp102's sitting in boxes...

btw, you need to look for high fs drivers, with large xmax for a TH, which limits the driver choices considerably. For instance, a 51hz fs delta 12pro-a models well, but still exceeds xmax at 100watts, where it's only giving 119db flat from 40 on up in a 220liter TH cabinet.

If you want to go TH, the 3015lf is your best bet. Here's what they'll do in a single and 4 box combo at 56volts. (without exceeding xmax above 35hz)

Compare that to my 'little' 55-2421 cabinet, 1 and 4 boxes, and you'll see why I kinda like the mcm's in FLH, and the 3015lf in TH.
 

Attachments

  • 300L-th.JPG
    300L-th.JPG
    41.9 KB · Views: 800
  • 55-2421flh-40v.JPG
    55-2421flh-40v.JPG
    44.1 KB · Views: 780
Last edited:
Jbell thank you for the info. I read your thread "Dual MCM FLH". What does FLH stand for? Front loaded horn? Do you have any more info you would share on your dual 55-2421 cabinets?

So how big of a box would it be for a TH with 3015lf?

If you want to sell your BP 102's just let me know how many and how much$.

Thanks Mike
 
sorry, bp102 doesn't model well AT ALL as a TH.

Hmm, just 'running the numbers' I got these dual alignments, but between being fairly large and with a limited Xmax probably not worth the wood/effort for a prosound app though:

~18 Hz/753 L:
~28 Hz/552 L:

GM
 

Attachments

  • Eminence Legend BP102 ~18 Hz conic TH.gif
    Eminence Legend BP102 ~18 Hz conic TH.gif
    20.9 KB · Views: 753
  • Eminence Legend BP102 ~28 Hz conic TH.gif
    Eminence Legend BP102 ~28 Hz conic TH.gif
    20.9 KB · Views: 733
GM
That was the problem He wants PA subs.
Out of curiosity.
What are your HR inputs on that?
The dual version I came up with when he asked hits 115 DB MAX at 23 Hz.
Not to bad for a HT sound system as you would be getting 6-10 DB more but in a PA environment you aren't. So it is pretty useless.

Mike - i replied to your other thread.
Sorry mate I am slow... wait ... no I am just almost always doing something. Its 2:19 AM here. Need to get to bed for work ...
 
"sorry, bp102 doesn't model well AT ALL as a TH.......If anyone else knows of a good bp102 cabinet, let me know."

Well, I responded to the above and believe I succeeded where he claimed to have failed if the published specs are reasonably accurate, though I did concede it's probably not suitable for a prosound app. Just because it's not doesn't mean it's de facto useless for ANY TH app since the 18 Hz one stuffed into a typical room will in theory meet DD/DTS/THX reference of 115 dB/20 Hz/viewing position with as little as 10 W.

That said, in looking up its Xmax/Xlim, I found two radically different sets of specs from Eminence, so without measured specs, just ignore them.

GM
 
I should learn to be more accurate in my statements GM: Yes, your TH sims are quite valid. I guess I should have said that I can't get reasonably flat response from 40-100hz, at around 100db@1w/1m (single driver) in a 'reasonably' sized pa cabinet. (The OP was looking for small, small, small...) and be able to use the rated input power of the driver before hitting xmax.

That's kinda my works/doesn't work rule of thumb when I try sims for pa use, which explains also why I've never successfully found a good PA TH option for a 55-2421. (I've spent HOURS on that one....)

Thanks for the sims though, it would have never occurred to me, to try a bp102 in a HT TH. I may have to do some more looking at that driver, I took them out of my T39's before roasting dogs...
 
What we really need is a separate prosound forum as some others do and I've asked more than once for one with no response, but was hoping it would be added in the upgrade.

So, yeah, prefixing any prosound centric thread description with the word 'prosound' would be nice, i.e. Prosound: Help with a tapped horn

Why a set efficiency rather than a set sensitivity, or better yet, a set half power peak SPL/30 ft as was once the norm?

Yeah, split in two to allow more placement flexibility and combined with some room gain, it has a lot to recommend it.

GM
 
Funny how DIY Pro Sound is shun apon in the US. Except by Danley.

??? If you mean by folks like me, I've no problem with it per se and have done quite a bit of it for others back when the IRS was more lenient WRT to 'bartering' taxable income, but openly soliciting/publishing design details of currently patented or applied for designs beyond the publishing of its legal docs is a no-no for me.

Tom is the quintessential DIYer and I know he would love to 'bench race' his and others designs in depth like he sometimes did on the late 'basslist', but he has his own business now with a family depending on him, so obviously he has to protect his interests as best he can. Fortunately, he has the rare ability to hide much of his product's design theory in plain sight for those who know what to look for, so at least he gets to 'scratch' this particular 'itch' a little bit.

WRT general construction techniques, the net's littered with them, but I guess it would be nice to have our own.

GM
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.