A speaker physics question.

GM · September 21st, 2011, 04:09 AM

Yes, once you understand horn design theory.

Your design is a simple pipe horn with no well defined low pass filter [the front chamber of a FLH]. The 'BIB' calculator will spit out a simple conical/parabolic pipe horn. Viewed another way, a horn's filter chamber is a typical vented speaker box where the vent opening is the throat of the horn, so once you understand what you're trying to do, you can design a good enough scoop horn using a simple vented box calculator such as BoxPlot or similar.

I haven't read them, but MJK has written some papers on horn design that will probably be helpful and for sure, any typical speaker design will sim more realistically using his MathCad software than HR's 'ideal', no damping, plots that tend to be very misleading if you don't know how to interpret them: Horn Theory

Anyway, there was a design routine posted on the DIYaudio 'full-range' loudspeaker forum several years ago that folks were satisfied with its results, but unfortunately I've lost the link and don't recall the author, but searching the forum should turn it up for you.

GM

**Old Guy** · September 21st, 2011, 05:19 AM

It seemed worthwhile at this point to post the following links...slight trepidation involved don't want anybody to get overwhelmed...but lots of good stuff

Marshall Leach's site

W. Marshall Leach, Jr.

DB Keele's site

AES Papers -- Official website of D.B.Keele

**cradeldorf** · September 21st, 2011, 02:16 PM

Originally Posted by GM

Yes, once you understand horn design theory.

Your design is a simple pipe horn with no well defined low pass filter [the front chamber of a FLH]. The 'BIB' calculator will spit out a simple conical/parabolic pipe horn. Viewed another way, a horn's filter chamber is a typical vented speaker box where the vent opening is the throat of the horn, so once you understand what you're trying to do, you can design a good enough scoop horn using a simple vented box calculator such as BoxPlot or similar.

I haven't read them, but MJK has written some papers on horn design that will probably be helpful and for sure, any typical speaker design will sim more realistically using his MathCad software than HR's 'ideal', no damping, plots that tend to be very misleading if you don't know how to interpret them: Horn Theory

Anyway, there was a design routine posted on the DIYaudio 'full-range' loudspeaker forum several years ago that folks were satisfied with its results, but unfortunately I've lost the link and don't recall the author, but searching the forum should turn it up for you.

GM

Thanks Greg, I am attempting to read all that Martin king wote on BLH designing.. needless to say he' makes me feel more retarded than I already did.

I'll try your way too, Great info. Thanks again.

**cradeldorf** · September 21st, 2011, 02:17 PM

Originally Posted by Old Guy

It seemed worthwhile at this point to post the following links...slight trepidation involved don't want anybody to get overwhelmed...but lots of good stuff

Marshall Leach's site

W. Marshall Leach, Jr.

DB Keele's site

AES Papers -- Official website of D.B.Keele

Thanks OG, I'll try these too.

Maybe between all of it It'll start to jive.

**cradeldorf** · September 21st, 2011, 03:25 PM

Ok questions about the BIB calculator, Am I supposed to just fill in the FS,Vas and QTS and let the program do the work or am I supposed to fill in all the blanks? and If so I'm stuck on # 10 and 11 (depth internal - width internal) what do these mean? also if I am supposed to fill in the other info can I use sq,in for the VB and SM? because that's what I did. My speaker is in column C.

Never mind I figured it out....it's friggin huge!! can I fold the horn more? 125" is pretty damn long.

**cradeldorf** · September 21st, 2011, 05:16 PM

Ok if I can fold it more here is what I came up with, although the VB does not include the boards inside that create the horn and also The 247 inch line length is from box end to box end instead of to the middle of the turns.