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Beowulf57
09-14-2008, 04:34 AM
Does anyone have the throat diameter and length of the inner horn of the LE85/2420 driver which leads from the phasing plug to the 1" diameter exit mouth?

Robh3606
09-14-2008, 07:50 AM
If you have a program like photoshop you can scale it in pixels. You can scale from the 1" driver throat exit. The L300 crosssection in the brochure comes to mind.

Rob:)

Beowulf57
09-14-2008, 01:48 PM
Thanks Rob! So, using Photoshop (a pseudo vernier caliper), I get 11/16" for the throat diameter and 2&1/8" for the length. Now...I can calculate the fc for the LE85/2420 using the 2307 and the 2312 horns.

Beowulf57
09-14-2008, 08:11 PM
Using the dimensions from the photo I get the following:

HL91/2307

L= 8.5 + 2.125 = 10.625"

Throat Area = .371

Mouth Area = 12.571

m = 13.031

fc = 354Hz


HL92/2312

L= 11.5 + 2.125 = 13.625"

Throat Area = .371

Mouth Area = 12.571

m = 10.162

fc = 276Hz

Anyone...please feel free to verify my calculations.

This suggests that the 2312 horn should be better than the 2307 with the LX5 crossover which is down 7.5-9dB at 500 HZ and down 18dB at 300Hz. However, I still think the 2307 is workable at the 500Hz crossover with this network and wonder if the "horny" sound has more to do with the issue of rolling off the top end as occurs when using the 2405H and 3106 to make a 3-way system?

I'll report more after installing the HL92/2312 horns with my LE85s and comparing that setup to the use of the HL91/ 2307 configuration.

Chas
09-15-2008, 08:08 AM
a 3-way system?

I'll report more after installing the HL92/2312 horns with my LE85s and comparing that setup to the use of the HL91/ 2307 configuration.

That will be interesting. I have done it at 800 Hz, but unfortunately did not have any measurement equipment at the time.:(

Beowulf57
09-15-2008, 09:47 AM
That will be interesting. I have done it at 800 Hz, but unfortunately did not have any measurement equipment at the time.:(

Yo Charles :bouncy: how's it hangin'? my 2312s should be here shortly and then I'll see what my innate biological measurement system tells me. Battle of the :duel:horns.

Zilch
09-15-2008, 12:49 PM
This suggests that the 2312 horn should be better than the 2307 with the LX5 crossover which is down 7.5-9dB at 500 HZ and down 18dB at 300Hz. However, I still think the 2307 is workable at the 500Hz crossover with this network and wonder if the "horny" sound has more to do with the issue of rolling off the top end as occurs when using the 2405H and 3106 to make a 3-way system?This is REALLY easy. You put them on an active crossover with adjustable frequency and dial it around listening for the onset of "coloration."

I have also measured both combinations, and the results are posted in these forums.

The question remaining outstanding is whether you'll be able to perceive the piss running back down the rope.... :p

Beowulf57
09-15-2008, 01:32 PM
This is REALLY easy. You put them on an active crossover with adjustable frequency and dial it around listening for the onset of "coloration."

I have also measured both combinations, and the results are posted in these forums.

The question remaining outstanding is whether you'll be able to perceive the piss running back down the rope.... :p

Don't got no active crossover, but can you point me to the HL92 "results?"

If it's horse piss :shock:, I'll have no trouble :nutz:perceiving it :slink:!

Beowulf57 :rotfl:

Zilch
09-15-2008, 01:54 PM
Get one, if you're gonna dork around with this stuff. $99 for Behringer CX3400, new.

http://audioheritage.org/vbulletin/showthread.php?p=138889#post138889

Beowulf57
09-15-2008, 02:10 PM
Get one, if you're gonna dork around with this stuff. $99 for Behringer CX3400, new.

http://audioheritage.org/vbulletin/showthread.php?p=138889#post138889

Okee dokee.:rockon2: And my appreciation to you for the HL92 sweep link:cheers:
You are a gentle man and a scholar.

toddalin
09-15-2008, 02:36 PM
I also got a set of the 2312s off the bay a couple weeks ago and am about ready to install them. I'll probably get to it next week as I'm doing the garden railroad open house this weekend.

Anyway, for a little encouragement, these are the "bumps" I made to cover the holes in the back of the L200 cabinets. My cabinet backs are primer grey and these match.

The frames are 2"x2" (actually 1-1/2"x 1-1/2", but that's what they call it), and the backs are a piece of 5/8" high density shelf board that has a laminate coating. The corners were cut at 45 degrees and everything is attached with Titebond II and brads. Speaker banting insulation is glued to the inside rears.

http://www.largescaleonline.com/eimages/lsolpics/Team_Member_Pics/toddalin/Concrete_Rocks/index_002.jpg

http://www.largescaleonline.com/eimages/lsolpics/Team_Member_Pics/toddalin/Concrete_Rocks/index_003.jpg

Beowulf57
09-15-2008, 03:05 PM
I also got a set of the 2312s off the bay a couple weeks ago and am about ready to install them. I'll probably get to it next week as I'm doing the garden railroad open house this weekend.

Anyway, for a little encouragement, these are the "bumps" I made to cover the holes in the back of the L200 cabinets. My cabinet backs are primer grey and these match.

The frames are 2"x2" (actually 1-1/2"x 1-1/2", but that's what they call it), and the backs are a piece of 5/8" high density shelf board that has a laminate coating. The corners were cut at 45 degrees and everything is attached with Titebond II and brads. Speaker banting insulation is glued to the inside rears.

http://www.largescaleonline.com/eimages/lsolpics/Team_Member_Pics/toddalin/Concrete_Rocks/index_002.jpg

http://www.largescaleonline.com/eimages/lsolpics/Team_Member_Pics/toddalin/Concrete_Rocks/index_003.jpg

Very nice looking work! In my case, the longer horns will fit neatly inside the cabinet that houses the LE85s on top of the folded horn cabinets...so a bit less work than you have had. Also, the 23" wide cabinet in conjunction with the front face of the folded horn cabinets provides the desirable baffle for the horn/lens...which your L200 cabinets already provide. I will be most interested to hear your results with the longer horn.:D

subwoof
09-15-2008, 06:06 PM
if you do a search using my ID you will find pix and measurements on this throat from over a year ago..

And this:

http://audioheritage.org/vbulletin/showthread.php?t=20349&highlight=2312


sub

Beowulf57
09-15-2008, 07:01 PM
if you do a search using my ID you will find pix and measurements on this throat from over a year ago..

And this:

http://audioheritage.org/vbulletin/showthread.php?t=20349&highlight=2312


sub

Thanks subwoof. I found this thread: http://audioheritage.org/vbulletin/showthread.php?t=2171 which provides a length of 2" for the throat (my pictorial measure was 2.125) but no pics and no throat diameter for the 2420. Any other links?

subwoof
09-16-2008, 08:42 PM
LE85 = 2420

The paint and shape of the rear cap are the only differences.

The same throat is on all the smaller alnico's also.

Beowulf57
09-17-2008, 10:41 AM
LE85 = 2420

The paint and shape of the rear cap are the only differences.

The same throat is on all the smaller alnico's also.

Yo subwoof,

Yes I know the LE85 = 2420. I did find two references in that thread to the depth of the integral horn in the CD: 2" and 1.875", however the only reference to the throat diameter is a guess from reVintage:

"1" driver(guessed throat dia at phaseplug is 3/4") + 2307 350Hz flare, 1kHz Fu"

My "pictorial calculation" gave me 2.125" for length and .6875" (11/16") for the throat diameter...so I'm in the right range and my original calculations for fc are probably not too far off.

Thanks

Beowulf57
09-24-2008, 07:02 AM
Thanks for all the help: results posted here: http://audioheritage.org/vbulletin/showthread.php?p=222028#post222028