Trying to learn and have alot of questions

[chrapladm]

I am trying to design a tractrix horn like this one:
jc's tractrix bass bin
Now I would like to build his exact horn but it is 40" wide and I only have about 30-32" of width to fit a horn.

So with my very limited knowledge I am trying to figure out how to design something that looks very similar to his but only 32" wide and can play atleast 70-600hz like his.

I have read alot of others back loaded horn builds but keeping getting lost with all the technical stuff. I am wanting to build a front loaded horn but have been just reading what I can.

SO I am sorry if there are alot of easy questions for everyone but I figured this would be easier than PM'ing everyone questions.

So if Using the 3012LF for a driver how do I figured out the rest.

[planet10]

Since how low a bass horn can go is based n its mouth size, by compromising the mouth size you will not be able to go as low. Theory suggests the horn at the link will reach 85 Hz at bst, a tractix really needs to be designed even lower to hit th target, so this likely only hits 120 Hz. By going smaller (32") you could hit 105 Hz, probably 150 at best in practise. A midrange horn, not a bass horn.

dav

[PLB]

If you haven't done so already, I would suggest you try David McBean's software here Hornresp -- it's free.

Regards

Peter

[chrapladm]

Thanks Dave and Pete. I will have to download Hornresp for this computer. I didn't think it did horns though?

The designer in the above link was able to hit around 80hz in room away from the wall and corner about 2ft.

I was going to build a La Scalla bass bin and add a top horn later. I have always loved the Klipsch builds and they are also very easy with children.(Kids poking stuff)

Now the linked horn I would have to add a small screen or something but thats not to worry. But before I build a LS bass bin I thought about trying to do a tractrix horn like the linked.

I think anywhere below the directional frequency would be fine for a start. So I would like to go down to 75/80 but if 100-105 is more reasonable then thats what I will have to work with. Now right now I have a THT horned sub that when it goes down to the horns bottom design of 20hz it still can reach down to around 17hz. Now if my room was better designed for low frequency then it would be able to go lower which others have but I cant.

So in that thinking if I designed a horn that went down to 105hz might it be able to reach 90hz or do horns drop very fast?

And how do I go about figuring out a horn design for something like tractrix horn for 105hz to around 5-600hz?

And realistically with in room response what is the smallest the mouth would have to be to get a horn down to 70-80hz?

[Altec Best]

The LaScalas aren't really well known for their bass.The Cornwall is the only Klipsch that puts out any kind of bass IMO.

You may like the way that horn looks but by cutting it down, I don't think it will perform to your liking.As noted it will be more like a mid horn i think.

[chrapladm]

Ok so after searching for awhile I just got lost and decided to work on my ULF wants. I finally decided on some sealed subs that will be here in a few months.

Now I am back to the midbass horn wants. Are there any horns out there that others have done that can fit into a 22" width space?

And if this is my limits for width what is my realistic low frequency cutoff for a horn?

I would love to have a dual JBL 2242 18" cabinet tuned to 42hz and go up to 500hz but will never be able to afford that. SO can I achieve tactile bass like a ported 15 or 18 in a horn with only 22" width?

Or am I best to just go with a ported cab?

Even if I do go ported cab I would only be using a single 12" or maybe dual Bob Crites 12's per cab. I would use the subs to 80hz at least but I have always been missing the great midbass from 60-350hz you get from low tuned dual 15 or even 18 cabinet.

Sorry if it seems I have not done any searching but life has gotten most of my time and I dont always visit this forum. But I have always read some great horn threads on this forum.

[norman bates]

if you want great midbass, you can always do a 2x15" with large horn (like my favorite setup) tuned to 30hz (sounded better than 40hz). I cross at 750hz. And the eminence drivers won't break the bank.

Norman

[chrapladm]

Whats the width on your cabinet in your avatar?

I know I could go with dual 15's but was always wondering if there was a horn design that came close.

Do you use a sub also.....if so what do you cross it over at?

[norman bates]

no sub, it's the jbl 4508a cabinet, 25" wide I think. 8ft3 with dual ports, 1 stuffed. The box is about 1/2 sized for a perfect ported box, but oh well. Checking winisd, the response is livable. Nope, no subwoofer. It does go low, you just have to turn it up to hear it (darn fletcher munson curve). I've had many a setup, but this one just makes you smile. Fun dynamic, impact, punchy, slamming bass, way better than flat measuring 8" drivers crossed at 80-100hz to subwoofers, yuck. I don't know if it is the lack of distortion, less crossover points, sharp leading edge of a compression driver, 24db somewhat time alignment, or sheer cone area going up into the mids. My klipsch rb-75 has cleaner mids and highs, but I don't care.

Getting a mid/high horn that's big enough, a compression driver that goes high enough, and decent dispersion, is difficult. I (when the mood suits me) use the ev cd-horn hr90 with an ev dh7 (with cd-eq boost on in the crossover) and a resistor/cap circuit to cut a bit under 8khz. There are not many less echo-y horns, like the mcm 54-580 6.5" horn (2khz crossover point), probably any stereo lab horns (but tractrix narrows dispersion up high), the oblate spheroid, peavey quadratic horn, or any of the avantegarde. I also wrap the mouth of my horn with foam (cleaner, less echo).

I (my buddy) is working on a 2.5 way with 8" silver flute and the mcm round horn zaph used, but with a jbl 2407a compression driver. Initial tests are awesome, like a very expensive small 2 way, very clear, best sound yet according to my wife. Not much bass (strong magnet on the 8"), but very smooth (love the wool). Still need to cut the mid highs for a flatter response, it got harsh after 1/2 an hour once I figured what was going on. But it is an entirely different design with different goals.

Bass horns are tough to do right, especially small, and for 100hz, you may need 3' of horn depth. And you need a strong magnet or forget going past 400hz. Even then, you will want for under 100hz. A simpler way is to do a 3-way with crossover points at 1.2khz and 200hz (compression driver and horn loaded midbass cab) then whatever you want from 200hz down. At least the horn mouths and depths will be manageable.

Lascala has some kick but the response is questionable (no bass) without a sub. See post #12
Klipsch Horn Woofer designs....

I miss a w-bin I had but I needed to be 15' away to get the bass. The bass was very different.

Norman

[chrapladm]

I have heard setups like yours before and have been very happy but always thought of having a w bin or other type. But that being said your suggestions in a 22" width will always be an option.

Maybe have to use 12's also. Just always wondering on different designs although the only thing I can say I have heard and I liked are the direct radiating types. I just figured maybe horn designs could achieve similar results. Maybe not with my limited space.

What are you using for your 700hz on up?
http://www.parts-express.com/pe/psho...70-204&scqty=2
I had thought of using these with a suitable CD.